SSL or TLS (Transport Layer Security) certificates are data files that bind a cryptographic key to the details of an organization. When SSL/TLS certificate is installed on a web server, it enables a secure connection between the web server and the browser that connects to it. The website's URL is prefixed with "https" instead of "http" and a padlock is shown on the address bar.
Motorola unveils $179 budget smartphone Moto G
The phone starts at $179 in the US without a contract. Contract-free prices for leading phones in the US typically exceed $600. The starting price is for a phone with 8 gigabytes of storage.
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Android 4.4 KitKat update is heading to Nexus 7 and 10 starting today
Google has announced that the newest Android update, KitKat is being rolled out to Nexus 7 and Nexus 10 devices starting today.
This update can be done using OTA. From the official Google+ page though, the roll out is happening first only to the Wi-Fi devices. Nexus 4 and Nexus 7 versions with mobile data will be getting the update soon, but no dates are defined.
Top 10 features of this update:
1. Just say “Ok Google”
You don’t need to touch the screen to get things done. When on your home screen* or in Google Now, just say “Ok Google” to launch voice search, send a text, get directions or even play a song.
2. A work of art
While listening to music on your device, or while projecting movies to Chromecast, you’ll see beautiful full-screen album and movie art when your device is locked. You can play, pause, or seek to a specific moment.
3. Immerse yourself
The book you're reading, the game you're playing, or the movie you're watching — now all of these take center stage with the new immersive mode, which automatically hides everything except what you really want to see. Just swipe the edge of the screen to bring back your status bar and navigation buttons.
4. Faster multitasking
Android 4.4 takes system performance to an all-time high by optimizing memory and improving your touchscreen so that it responds faster and more accurately than ever before. This means that you can listen to music while browsing the web, or race down the highway with the latest hit game, all without a hitch.
5. The future is calling
The new phone app automatically prioritizes your contacts based on the people you talk to the most. You can also search for nearby places and businesses, your contacts, or people in your Google Apps domain.
6. A smarter caller ID
Whenever you get a call from a phone number not in your contacts, your phone will look for matches from businesses with a local listing on Google Maps.
7. All your messages in the same place
Never miss a message, no matter how your friend sends it. With the new Hangouts app, all of your SMS and MMS messages are together in the same app, alongside your other conversations and video calls. And with the new Hangouts, you can even share your location and send animated GIFs.
8. Emoji everywhere
Sometimes words can’t express how you feel. For that, there’s Emoji, the colorful Japanese characters, now available on Google Keyboard.
9. Print wherever, whenever
Now you can print photos, documents, and web pages from your phone or tablet. You can print to any printer connected to Google Cloud Print, to HP ePrint printers, and to other printers that have apps in the Google Play Store.
10. Pick a file, any file
From apps like Quickoffice, you can open and save files on Google Drive, other cloud storage services, or your device. And with quick access to recently used files, it's easier than ever to send the file you were just working on.
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Tablets vs PCs
Check Out Brian Madden in this IT Consumerization video 'Tablets vs. PCs' brought to you by Intel. To learn more, please visit the IT Consumerization Corner at Tech Target, brought to you by Intel: http://searchconsumerization.techtarget.com/IntelITConsumerizationCorner
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A crash course in GSM, GPRS, EDGE, UMTS, HSPA, LTE and WiMax
This is almost a crash course in fundamentals on mobile standards. It does not matter if you are just a common man trying to understand the jargon or a professional who is trying to get a grip of things. This article i hope will help you started off :-) Please leave a comment if you don't understand any topic. I am very happy to clarify.
To understand Timeslots and frequencies you can read here!!
GSM stands for Global System for Mobile Comm. This is the most popular 2G protocol standard in the world. It is by law the only system deployed in Europe and is used in many other locations around the world. As a digital standard, GSM can carry both voice and data, although the maximum data rate per channel is only 14kbps. North America, Korea, and pockets worldwide use another 2G standard based on CDMA technology; this protocol, CDMAOne, was developed by Qualcomm and is also known as IS-95 or, more commonly, CDMA. GSM is based on time-division multiple access (TDMA) technology, in which a single frequency is divided into eight time slots, with each caller using a particular slot. Most GSM networks operate in two frequency bands: 900MHz and 1,800MHz. In North America, however, the allocated frequency bands are 850MHz and 1,900MHz. Thus, to support global roaming, a handset must support all four GSM bands. The frequencies in each band are assigned to either the downlink direction (from the base station to the user) or the uplink direction (from the user to the base station). Each band supports 124 carrier frequencies in each direction (uplink and downlink).
GPRS stands for General Packet Radio Service. This is a 2.5G protocol standard which allows a single handset to use up to four slots for the downlink and four for the uplink, thus consuming the entire frequency. Using a more efficient encoding than GSM, GPRS can transmit 20kbps per slot for a maximum of 80kbps in each direction using four slots. A later enhancement, EDGE, increases the data rate to a theoretical maximum of 384kbps, although the most bandwidth supported by any chip vendor or carrier is 240kbps.
EDGE stands for Enhanced Data GSM Environment is a 2.75G protocol standard, which increases the bandwidth of each time slot to 48kbps. Baseband processors commonly support either Class 10 or Class 12, which allow a maximum of four slots (192kbps) on the downlink.
UMTS stands for Universal Mobile Telecommunications Service which is a 3G standard and is a follow-on to GSM, created by ITU. (Japanese carrier NTT DoCoMo uses a pre-standard version of UMTS known as FOMA.) UMTS uses new spectrum at 2GHz and new air interfaces that can carry more data, and therefore a greater number of digital voice calls, than can 2G technologies. UMTS delivers symmetric data rates as high as 384kbps for handsets. Unlike earlier standards, UMTS supports simultaneous voice and data services (dual-transfer mode). With tremendous growth in cell-phone usage during the 1990s, vendors sought to use new frequency bands and new technologies to increase capacity. The term 3G indicates the generational leap involved in this major change. The first 3G network was deployed by NTT DoCoMo in Tokyo in 2001. Today, 3G is broadly deployed by operators around the world. Most operators, however, have not upgraded their entire networks, so 3G devices must include 2G compatibility to have the widest service area.
Qualcomm has continued to develop its own CDMA2000 air interface, thus providing its operators with an upgrade path. The 3G version, known as EV-DO, was first deployed in Korea in 2002. Since then, it has been broadly deployed in North America and other locations. The initial version, called Revision 0 (zero), supports data rates up to 2.4Mbps. Approved by the ITU in 1999 and officially adopted by China in January 2006, TD-SCDMA is a 3G standard deployed primarily by China Mobile, starting in 2008. As the name implies, this air interface combines TDMA and CDMA techniques, but the general characteristics and data rates are similar to those of UMTS. The TDMA aspect of the standard enables use of the same spectrum for both the uplink and downlink, thus providing some flexibility. TD, as the TD-SCDMA standard is sometimes called, provides aggregate data rates of 2Mbps.
HSPA stands for High-Speed (Uplink) Packet Access which is a 3.75G standard. This combine both HSDPA and HSUPA as explained in the next oaragrapgh. As with 2.5G technologies, new technologies enhance the data rates of UMTS while maintaining radio compatibility. The first to ship was HSDPA, which was first deployed in late 2005. HSDPA reserves a portion of the UMTS spectrum and converts it into a new high-speed downlink band. This 14.4Mbps band is shared by all users that are actively downloading data; as with any shared medium, actual bandwidth depends on how many users are simultaneously sharing the downlink band. The amount of data that each handset can accept may be limited.
HSUPA addresses the uplink. This direction is of concern for handset users wishing to transmit high-resolution photos or video. HSUPA raises uplink speed as high as 5.76Mbps. Initial commercial deployments began in early 2007. By pushing peak data rates to several megabits per second, HSDPA and HSUPA (together called HSPA) can also be used to deliver cellular broadband services. The data bandwidth using these technologies is similar to what older DSL and cable modems deliver.
HSPA+ further boosts data rates using two approaches. One uses a higher-order modulation to pack more bits into the signal; the second adds MIMO (multiple input, multiple output) capability, which can double throughput by transmitting two streams at once. To do so, MIMO requires two antennas at the base station and two antennas on the handset. The two approaches can be used separately or can be combined to achieve 42Mbps.
The TD-SCDMA standard can be extended to support faster downlink and uplink speeds using the same techniques that are defined in HSPA. The enhanced protocols are referred to as TD-HSDPA and TD-HSPA. Advancing CDMA2000, Qualcomm developed EV-DO Revision A, which boosts data rates as high as 3.1Mbps on the downlink and 1.8Mbps on the uplink. The new EV-DO Revision B supports 14.7Mbps on the downlink and 5.4Mbps on the uplink; these data rates are similar to those of HSPA. Qualcomm sampled the first EV-DO Rev B chips in late 2008.
LTE - Long Term Evolution
The UMTS camp has developed a 4G technology called Long-Term Evolution (LTE). The specification was completed in January 2008. In December 2009, TeliaSonera deployed the first commercial LTE network in Norway and Sweden. LTE uses a new modulation technique, OFDM (orthogonal frequencydivision multiplexing), and wider (20MHz) channels to deliver a peak data rate of 100Mbps. Optional MIMO support raises the peak rate to 326Mbps in a four-antenna configuration. Because of the space required for multiple antennas, high-end handsets and data cards are likely to use one or two antennas, whereas fixed broadband modems may use four (assuming the carrier supports that mode at the base station). The peak uplink rate is 86Mbps.
As a result of these changes, LTE provides about three times the spectral efficiency of HSPA, meaning that an operator can triple the data rate (or the number of voice calls) using the same set of frequencies. Thus, LTE should eventually reduce the cost of data services significantly. Deploying new base stations and bringing down the cost of LTE modems and handsets will require several years, however.
Another 4G technology is WiMax. Originally developed by Intel for fixed wireless broadband, WiMax is being used by some mobile service providers. WiMax is defined by the IEEE as 801.16. An industry group, the WiMax Forum, promotes the standard and certifies products for interoperability. Originally conceived as a data standard, WiMax can be used for voice as well. Like LTE, WiMax uses OFDM with channels widths of up to 20MHz. WiMax also supports MIMO. WiMax has a theoretical maximum capacity of 75Mbps, but mobile users will receive no more than 25Mbps—a far lower rate than that provided by LTE. For fixed WiMax, the practical peak rate is 45Mbps. An important difference is that WiMax, unlike LTE, is not optimized for power consumption on the uplink, making it less power efficient for handheld devices. According to the ITU, 4G technologies must deliver data rates of at least 1Gbps. Neither the first generation of LTE nor the initial mobile WiMax deployments meet this criterion, but both are generally considered to be 4G technologies because they use OFDM. As a follow-on to LTE, LTE Advanced is expected to be the first cellular standard to meet the ITU’s 1Gbps goal.
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Apple launches iPad Air, newer iPad Mini, MacBook Pro and Free OS X Mavericks
In its annual pre-holiday unveiling event, Apple Inc has announced the iPad Air its fifth-generation iPad, iPad Mini and MacBook Pro.
The iPad Air is Thinner and lighter with a powerful processor. The 9.7-inch Retina Display with other added features brings some design and performance enhancements to the best-selling tablet. The Touch ID finger print sensor is missing which would have been a great addition. A new A7 chip inside makes it 8 times faster than the iPad 4, according to Apple. This same 64-bit chip also in the iPhone 5S, the Air's A7 also comes with the M7 motion co-processor, which promises graphics that render at twice the rate of the previous iPad without sucking more juice than the previous gen. Though the slimness and weight are the two significant features, overall from my point of view it is a delicate high tech piece of junk.
The iPad Mini has the same A7 processor as the iPhone 5S and iPad Air, packs in as many pixels as the Retina display on the full-size iPad Air. The new iPad Mini has a higher pixel density on its display than its big brother, at 326 pixels per inch. Can your eyes spot the difference at this form factor? Apple has boasted that the 7.9-inch Retina display on the iPad mini offers a 35 percent larger area than screens with 7-inch tablets. It is also the only small tablet to deliver Apple's full iOS ecosystem and App Store. The new Retina iPad mini features two antennas to support Multiple-In-Multiple-Out (MIMO) technology, bringing twice the Wi-Fi performance at 300Mbps. Cellular models also come with expanded LTE coverage to accommodate even more LTE networks worldwide, while continuing to deliver comprehensive support for other fast cellular technology around the world (DC-HSDPA, HSPA+), all in a single model.
The new MacBook Pros have slimmed down for the 13-inch version, which is now only 0.71 inches thick. They got significant spec bumps, however, including new Haswell Core i5 and i7 processors and next-generation integrated graphics from Intel. Among others, both the 13- and 15-inch MacBook Pro models received PCIe-based flash storage with up to 60 percent faster read speeds than previous models. In addition, the laptops were brought in line with the MacBook Air lineup and now feature 802.11ac Wi-Fi connectivity. Battery life has been boosted as well, with the smaller model now lasting up to nine hours, while the 15-inch Pro can run for eight hours on a single charge.
Finally, Apple has officially released its latest operating system, OS X Mavericks for free. Mac users can install it immediately.
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LG G2 is one of the Fastest Android Smartphones On the Market
In the ever-expanding smartphone war, the only two mobile phone manufacturers making any notable profits at present are Apple (with iOS) and Samsung (with Android). Despite Android togather with Samsung dominating the global market share, players such as LG, HTC, Pantech, and Sony are scrapping for market share as well.
The LG G2 is the follow-up to LG's Optimus G Pro.
It is one of the few smartphones on the market powered by Qualcomm's Snapdragon 800 quad-core SoC.
The G2 sports a 5.2-inch 1080p display, 2GB of RAM and up to 32GB of on board storage. However, the 2.26GHz quad-core Snapdragon 800 chip on board also has Qualcomm's Adreno 330 GPU that even gives NVIDIA's Tegra 4 a run for its money in gaming and graphics performance.
Though the G2 has a rather unorthodox volume rocker and power button assembly on the back of the phone, once you get used to the location, it's actually a pretty comfortable system.
What's pretty impressive though is the G2's performance combined with its 3000mAh battery that offers a solid balance of horsepower and battery life and rivals flagship phones like the Samsung Galaxy S4 and Apple's iPhone 5S.
Specifications and features:
Processor and memory
2.26GHz quad-core Qualcomm Snapdragon 800 CPU
2 GB RAM
16GB or 32 GB internal memory
Operating System
Android 4.2.2 (Jelly Bean)
Connectivity
UMTS: Band I (2100);UMTS: Band IV (AWS)
UMTS: Band IV (1700/2100);Band II (1900);Quad Band GSM;LTE
802.11a/b/g/n (Dual-Band) Wi-Fi
Mobile Hotspot
Bluetooth 4.0 LE+EDR
aGPS
USB 2.0
Ports and expansion
3.5 mm audio jack
micro-SIM
micro-USB 2.0
Display
5.2-inch Full HD IPS (1,920 x 1,080) Display
Size and weight
5.45 x 2.79 x 0.35 inches (HxWxD)
5.04 ounces
Cameras and multimedia
2.4 MP HD Front-Facing Camera
13 MP Rear-Facing Autofocus Camera, Full HD Video Recording
Other features: Rear Volume + Power Toggles; Google Now; QSlide
Battery
3,000 mAh Li-Polymer
Super Deal: Nexus 7 Tablet for just $121 or INR7649 at Flipkart
Here comes the festival season and there is no better time for fabulous electronics deals. Nexus 7 is one such and the Indian retailer Flipkart is offering the Nexus 7 2012 version for just Rs 8999 and additional 15% off if you shop using your standard chartered credit card. The time is running out as the deal closes in less than half a day.
This offer has expired!!!!!
NEXUS 7 TABLET (WI-FI, 16 GB) PRICE: RS.8999
Key Features
7-inch HD Display with 216 ppi
16 GB Internal Storage
1.2 MP Front Facing Camera
Android v4.2 (Jelly Bean) OS
NVIDIA Tegra 3 Quad Core Processor
NFC (Android Beam)
Wi-Fi Enabled
Beautiful in a way the world has yet to see, Google captures the essence of all its expertise in technology and design in a tablet that is crafted to woo your heart and mind - the Nexus 7.
Changing The Way You See
With sharp images that change the way you will look at life, the 7 inch LCD IPS screen of the Nexus 7 with capacitive touch will transport you into another plane of clarity and brightness that adds a smoother dimension to everything that you use the tab for - be it playing your favorite game with amazing responsiveness from the tablet or reading the latest from your favorite author or even just chilling with a bit of jazz playing in the background - even videos come alive in full HD. With a pixel density of 216 ppi, the letters and photos are sharper and crisper than real print itself.
Serious Power
The Google Nexus 7 discreetly packs an NVIDIA Tegra 3 Quad Core processor with four cores and a backup of 1 GB of RAM to blow your mind away regardless of what you are doing - from taking down a grocery list, to watching a favorite movie, to launching Zomato to find a new brunch place to even playing a graphic heavy game, life is super fast with the Nexus 7.
Wherever you go
With a simple design complemented by a slim body and bestowed with a massive battery backup of 8 whole hours, the wi-fi enabled Nexus 7 comes with enough juice to get you through the day - especially handy when it comes to long commutes or boring waits.
Share and Have Fun
With the latest Android v.4.2 Jelly Bean operating system powering the tablet, the Nexus 7 from Google grants you a smooth yet simple interface that you could easily get addicted to. You can also share the tablet with the entire family with individual settings for each person. What’s more, with the Play Store at your disposal, you will never be in need for any apps.
Capturing Memories
A 1.2 megapixel camera with auto focus is what the Nexus 7 has on offer enabling you to capture every worthwhile moment with great clarity and perfection to relive when you feel like, later. The tablet also supports HD video recording that ensures that the best day of your life is captured and immortalized in the best possible way.
Who says technology is not art?
The Google Nexus 7 strives to prove otherwise.
A cheap mains operated led light circuit
An idea for the festival season. This basic circuit can be easily modified for 120v operation and more LEDs can be added as well.
Please use extreme caution while handling this circuit since the mains is not isolated and so there is a risk of heavy electric shock.
Broadcom begins layoffs of its LTE team
Post Japan based Renesas Electronics aquisition, the hatchet is on its own LTE design teams across the globe. The layoff started last week in San Diego, as well as in New Jersey, Colorado and India, sources say.
The figure could go substantially higher because the company expects to cut roughly $45 million in operating expenses relating to the deal between now and the next 12 months.
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The Economics of Smartphone Damage
A cell phone that is fed with beer at your favorite watering hole is likely not much useful. The following infographic provides an insight into the type, cause and cost of damages .
Open access shared folder is now active to share your files
Any reader can contribute files to the shared web folder.
This can be a document you created or just reference to some non-copyrighted files which you have come across. There is no registration required and neither do we have to invite anyone as a contributor. Just use the "SHARED" URL above and you have full access – including delete permissions – to the files in that folder.
Please give "5 Seconds for it to load fully :-)"
Apple CEO Tim Cook reflects on anniversary of Steve Jobs’ passing in letter to employees
On the eve of the second anniversary of the passing of Apple co-founder Steve Jobs, CEO Tim Cook reflects on the moment in a company-wide email.
Apple also has honored Jobs with a tribute video on its homepage.
Nexus 5 is revealed in a leaked Service Manual
LG’s New Nexus Phone Gets Detailed In Leaked Service Manual.
The new Nexus from LG will likely feature the inclusion of a 4.95-inch display, 1080p IPS screen, a 2.3GHz Qualcomm Snapdragon 800 with 2GB of RAM, 16/32GB variants, LTE radio and an 8-mp camera with optical image stabilization. Wireless charging and NFC are the likely new additions with no juice boost in the battery.
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World's first Carbon Nanotube based Computer
A Carbon Nanotube with its unique properties are a big breakthrough for electronics. Due to their thermal conductivity, mechanical and electrical properties, they find applications as additives to various structural materials. A team of Stanford engineers have taken this and built a basic computer harnessing the huge energy conservation capabilities and thereby promising to extend 'Moore's Law' for years to come.
Intel co-founder Gordon Moore's 1965 prediction that computer circuitry will keep getting smaller and cheaper to produce has held up. But as integrated circuits (ICs) keep getting more densely populated with transistors, the large amounts of heat they dissipate have prompted concerns over whether silicon can be used for many more generations of transistor shrinkage.
"People have been talking about a new era of carbon nanotube electronics moving beyond silicon. But there have been few demonstrations of complete digital systems using this exciting technology. Here is the proof," Mitra said in a statement.
Mihail Roco, senior advisor for Nanotechnology at the National Science Foundation, called the Stanford work "an important, scientific breakthrough". The research was led by Stanford professors Subhasish Mitra and H.S. Philip Wong.
Non-Synthesizable VHDL Code
RTL Synthesis is done by matching high level code against templates or patterns. It is important to use idioms that your synthesis tool recognizes. If you aren’t careful, you could write code that has the same behavior as one of the idioms, but which results in inefficient or incorrect hardware.
Most synthesis tools agree on a large set of idioms, and will reliably generate hardware for these idioms. This post is based on the idioms that Synopsys, Xilinx, Altera, and Mentor Graphics are all able to synthesize. We consider combinational loops to be unsynthesizable. Although it is obviously possible to build a circuit with a combinational loop, in most cases the behaviour of such a circuit is undefined.
Initial Values
Initial values on signals (UNSYNTHESIZABLE)
signal bad_signal : std_logic := ’0’;Reason: In most implementation technologies, when a circuit powers up, the values on signals are completely random. Some FPGAs are an exception to this. For some FPGAs, when a chip is powered up, all flip flops will be ’0’. For other FPGAs, the initial values can be programmed.
Wait For
Wait for length of time (UNSYNTHESIZABLE)
wait for 10 ns;Reason: Delays through circuits are dependent upon both the circuit and its operating environment, particularly supply voltage and temperature.
Different Wait Conditions
wait statements with different conditions in a process (UNSYNTHESIZABLE)
-- different clock signals
process
begin
wait until rising_edge(clk1);
x <= a;
wait until rising_edge(clk2);
x <= a;
end process;
-- different clock edges
process
begin
wait until rising_edge(clk);
x <= a;
wait until falling_edge(clk);
x <= a;
end process;
Reason: Processes with multiple wait statements are turned into finite state machines. The wait statements denote transitions between states. The target signals in the process are outputs of flip flops. Using different wait conditions would require the flip flops to use different clock signals at different times. Multiple clock signals for a single flip flop would be difficult to synthesize, inefficient to build, and fragile to operate.
Multiple “if rising edge”s in Same Process
Multiple if rising edge statements in a process (UNSYNTHESIZABLE)
process (clk)Reason: The idioms for synthesis tools generally expect just a single if rising edge statement in each process. The simpler the VHDL code is, the easier it is to synthesize hardware. Programmers of synthesis tools make idiomatic restrictions to make their jobs simpler.
begin
if rising_edge(clk) then
q0 <= d0;
end if;
if rising_edge(clk) then
q1 <= d1;
end if;
end process;
“if rising edge” and “wait” in Same Process
An if rising edge statement and a wait statement in the same process (UNSYNTHESIZABLE)
process (clk)Reason: The idioms for synthesis tools generally expect just a single type of flop-generating statement
begin
if rising_edge(clk) then
q0 <= d0;
end if;
wait until rising_edge(clk);
q0 <= d1;
end process;
in each process.
“if rising edge” with “else” Clause
The if statement has a rising edge condition and an else clause (UNSYNTHESIZABLE).
process (clk)Reason: Generally, an if-then-else statement synthesizes to a multiplexer. The condition that is tested in the if-then-else becomes the select signal for the multiplexer. In an if rising edge with else, the select signal would need to detect a rising edge on clk, which isn’t feasible to synthesize.
begin
if rising_edge(clk) then
q0 <= d0;
else
q0 <= d1;
end if;
end process;
“if rising edge” Inside a “for” Loop
An if rising edge statement in a for-loop (UNSYNTHESIZABLE-Synopsys)
process (clk) beginReason: just an idiom of the synthesis tool.
for i in 0 to 7 loop
if rising_edge(clk) then
q(i) <= d;
end if;
end loop;
end process;
Some loop statements are synthesizable. For-loops in general are described in the VHDL cookbook by Ashenden. For the curious reader, the above code is an 8-bit serial-to-parallel converter. The signal d is the serial data and q is the parallel data. On each clock cycle, d is copied into one of the bits of q.
For the synthesizable alternatives, please discuss/leave comments below.
We are now blog.digitalelectronics.co.in
We have a new look and feel to the articles that you loved most :-)
Your favorite blog, digitalelectronics.blogspot.com is now blog.digitalelectronics.co.in. Those who have already visited this blog since yesterday would have noticed a much simpler clutter free appearance while keeping the legacy features. We’ve refined the design and encapsulated the information accumulated over the years into an easily digestible and navigatable website. I am quite proud of it. In the coming months, i hope to improving this blog further so that it best serves you, the blog members.
Thank you.
Links & Resources (Link your website/blog)
This is an archive of the Links and Resources from the electronics web community submitted here so far. Please add your own link using the form below, but be advised that non related (spam) links will not be entertained.
A................................................................................................................
ASIC-System On Chip (SoC)-VLSI Design
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B................................................................................................................
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C................................................................................................................
CAD 4 VLSI
CAD and VLSI
Chip Design Made Easy
Coaching Excellence in IC Design Teams
Computer Harware links
Consciousness as the theory of everything
Cool Verification
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D................................................................................................................
Daniel Nenni
DeepChip
Design For Testability Blog
DFT Digest
Digital IC Design
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E................................................................................................................
e Verification
EET Design
EET Semi
EEWeb Electronics Forum - Electrical Engineering Community
Embedded System Design
Eric Schorn's Processors for People Blog
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F................................................................................................................
Fahrvergnugen
FPGA and DSP from scratch
FPGA Computing
Future of Design
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G................................................................................................................
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H................................................................................................................
Hardware Description and Verification Language
harry ... the ASIC guy
hdlsnippets - Releveant and accurate HDL snippets in verilog, system verilog and VHDL.
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I................................................................................................................
Industry Insights
IntelligentDV -Blog
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J................................................................................................................
John Cooley's DeepChip.com
John's Semi-Blog
JTAG
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K................................................................................................................
Kiran Bulusu's Blog
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L................................................................................................................
Linley Chips In
Listening Post
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M................................................................................................................
Magic Blue Smoke
My Electronics Blog
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N................................................................................................................
Nadav's Tech Adventures
Nanotech
Ninja ASIC Verification
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O................................................................................................................
Oh, one more thing
Olivier Coudert's Blog
On Verification: A Software-to-Silicon Verification
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P................................................................................................................
Pallab's Place
Practical Chip Design
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Q................................................................................................................
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R................................................................................................................
Reconfigurable Computing
RocketBlog - a discussion about all things related...
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S................................................................................................................
Semiconductor Glossary BLOG
skmurphy
Specman Verification
Studying and practicing Electronics
SysWip- For free open source SystemVerilog verification IPs.
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T................................................................................................................
Taking the Measure
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Acer Liquid C1: The Intel-powered Android 4.0 Phone
Intel and Acer have announced the Acer Liquid C1, an Android 4.0 smartphone at an event in Thailand.
Read more at: http://ibnlive.in.com/photogallery/12481.html?from=HP&utm_source=ref_article
Read more at: http://ibnlive.in.com/photogallery/12481.html?from=HP&utm_source=ref_article
Intel integrated LTE Modem + AP only in 2014
According to EETimes Intel is already shipping data only LTE modems to customers and data-and-voice multimode modem would ship during 2013. Intel is significantly lagging in the integrated modem and processor space that puts Intel way behind Qualcomm Inc., which already offers integrated LTE capability in its Snapdragon line of application processors. Intel's wireless capabilities are largely credited to the acquisition of wireless business unit of Infineon Technologies AG (Munich, Germany). This very team is known for its solid engineering capabilities while being cost effective and cost competitive.
Quick Introduction to LTE-Advanced
3G and 4G Wireless Blog: Quick Introduction to LTE-Advanced is an article written by Zahid Ghadialy where he explains LTE-A without going in technical details. This also includes the state of market on who is doing what.
LTE QoS Concepts & Architecture - Free Video Tutorials
Topics Covered: 1.What is LTE QoS? 2.QoS Tags 3.Bearer 4.QoS Management 5.PCRF Lecturered by: Yair Shapira
Nokia Lumia 900 is a Scrumptious Treat!
Any Nokia spy who has been sniffing around to get a foretaste of Nokia Lumia 900 would’ve had their plate full with all kinds of rumors. And now with the phone launched,and the rumor mills halted, we finally get to sink our teeth into the scrumptious device.
A little heads-up: The first bite is lip smacking!
Largest Ever
With a 4.3-inch display Lumia 900 is the largest smart phone ever conjured up by Nokia, often touted as Windows Phone’s flagship model. While the size has been upped, the design is clearly an evolution of Nokia Lumia 800, which in turn was an offshoot of Nokia N9 Meego. So if you ever get your hands on one of these babies, what you’ll have is a device much bigger in size than ever before with features that haven’t really been explored in the past.
Dazzling
Lumia 900’s massive screen is AMOLED and has a resolution of 800 x 480 pixels – which again is quite decent indeed. The text and icons on your phone will look sharper but it wouldn’t be excessively sharp on the display. Nokia ClearBack Display allows the screen brightness to modify itself in synchrony with the surrounding light making it more than viable to be used in any condition. The display is extremely bright and makes browsing or texting a dazzling experience.
Shade, Shape and Stone
Nokia Lumia 900 is available in three – black, cyan and white – colors, which adds to its aesthetic allure and diversity. And despite its monstrous size Nokia’s latest device is actually pleasing to the hand owing to its weight and shape. The cell phone weighs 160g – again decent, for its class and size – and measures 127.8 x 68.5 x 11.5 mm. In fact, its width is actually less than Lumia 800, hence adding to its user-friendliness and overall comfort.
Tweak or Two
There are a few variations from the Lumia 800, especially at the top of the Lumia 900. There is no plastic cover for the USB port, and change of access route for the microSIM port. There is also a slight change in the side function buttons; even so, their accessibility is as smooth as that of its predecessor.
Owing to the adjustment of the screen, there is an obvious layout reshuffle; most notably in the touch-sensitive navigation buttons. Plus a front-facing camera has been added to the design to facilitate video calling. And there is another 8-megapixel camera on the rear side which has dual-flash and also Carl Zeiss optics. The camera has the potential of conjuring up 3264 x 2448 pixel images, and has a 3x digital zoom to further add to the array of mouthwatering prospects.
The main menu is where Lumia 900 has sprung the biggest surprise: the user can now switch the front and rear cameras by a button’s tap! Not to forget the front camera giving 1280 x 720 pixel images via a 1-megapixel CCD.
Tango Time
Lumia 900 is the first handset to have Windows Phone Tango update. It might be bringing as many updates as Mango, but it still does speak volumes about the direction of the platform. And while Tango’s most significant new feature might be irrelevant to the Lumia 900, video attachment support in texts among other background tasks definitely add to the cell phone’s flavor.
Epilogue
Despite the bigger screen, Nokia Lumia 900 is incredibly user-friendly and sleek. The brightness of the screen is another highlight in this amazing device, which has been aptly coupled with a robust battery – much to the intrigue of a multitude of Nokia spies and cell phone scouts. If what you want is a Windows phone (one that accompanies a large screen) then look no further.
Author Bio
Jane Andrew writes about Nokia spy software and <a href="http://www.mobistealth.com/keylogger">keylogger</a> technology. She provides tips and news about cell phone and Nokia phone security. You can also follow her on Twitter @janeandrew01 to get the latest tips about nokia phone security and privacy.
A little heads-up: The first bite is lip smacking!
Largest Ever
With a 4.3-inch display Lumia 900 is the largest smart phone ever conjured up by Nokia, often touted as Windows Phone’s flagship model. While the size has been upped, the design is clearly an evolution of Nokia Lumia 800, which in turn was an offshoot of Nokia N9 Meego. So if you ever get your hands on one of these babies, what you’ll have is a device much bigger in size than ever before with features that haven’t really been explored in the past.
Dazzling
Lumia 900’s massive screen is AMOLED and has a resolution of 800 x 480 pixels – which again is quite decent indeed. The text and icons on your phone will look sharper but it wouldn’t be excessively sharp on the display. Nokia ClearBack Display allows the screen brightness to modify itself in synchrony with the surrounding light making it more than viable to be used in any condition. The display is extremely bright and makes browsing or texting a dazzling experience.
Shade, Shape and Stone
Nokia Lumia 900 is available in three – black, cyan and white – colors, which adds to its aesthetic allure and diversity. And despite its monstrous size Nokia’s latest device is actually pleasing to the hand owing to its weight and shape. The cell phone weighs 160g – again decent, for its class and size – and measures 127.8 x 68.5 x 11.5 mm. In fact, its width is actually less than Lumia 800, hence adding to its user-friendliness and overall comfort.
Tweak or Two
There are a few variations from the Lumia 800, especially at the top of the Lumia 900. There is no plastic cover for the USB port, and change of access route for the microSIM port. There is also a slight change in the side function buttons; even so, their accessibility is as smooth as that of its predecessor.
Owing to the adjustment of the screen, there is an obvious layout reshuffle; most notably in the touch-sensitive navigation buttons. Plus a front-facing camera has been added to the design to facilitate video calling. And there is another 8-megapixel camera on the rear side which has dual-flash and also Carl Zeiss optics. The camera has the potential of conjuring up 3264 x 2448 pixel images, and has a 3x digital zoom to further add to the array of mouthwatering prospects.
The main menu is where Lumia 900 has sprung the biggest surprise: the user can now switch the front and rear cameras by a button’s tap! Not to forget the front camera giving 1280 x 720 pixel images via a 1-megapixel CCD.
Tango Time
Lumia 900 is the first handset to have Windows Phone Tango update. It might be bringing as many updates as Mango, but it still does speak volumes about the direction of the platform. And while Tango’s most significant new feature might be irrelevant to the Lumia 900, video attachment support in texts among other background tasks definitely add to the cell phone’s flavor.
Epilogue
Despite the bigger screen, Nokia Lumia 900 is incredibly user-friendly and sleek. The brightness of the screen is another highlight in this amazing device, which has been aptly coupled with a robust battery – much to the intrigue of a multitude of Nokia spies and cell phone scouts. If what you want is a Windows phone (one that accompanies a large screen) then look no further.
Author Bio
Jane Andrew writes about Nokia spy software and <a href="http://www.mobistealth.com/keylogger">keylogger</a> technology. She provides tips and news about cell phone and Nokia phone security. You can also follow her on Twitter @janeandrew01 to get the latest tips about nokia phone security and privacy.
Lava XOLO X900 - AnandTech Review
Reader's in India, did you have a chance to try out this phone? would you buy/recommend it?
Lava XOLO X900 - World's first Intel phone
Discover what makes XOLO X900 with Intel Inside® the benchmark on speed and performance. Please head to the site directly by hitting the title.
Intel Mobile Comm's is looking for a Senior Verif Engineer
This opening is in Bangalore, India and the company is looking forward to close it at the earliest
Job Description:
1. About 5-7 years of experience in functional verification with at least 3-4 years in HVL's like E language/specman and System Verilog.
2. Good experience at both module and sub-system/SOC level verification
3. Good knowledge of Verilog/VHDL
4. Good knowledge of UVM/eRM methodology
5. Should have developed complete test bench architecture, designing and coding of test bench components like UVCs/eVCs including checkers, monitors, scoreboards, BFMs
6. Should have architected the test plan including functional coverage and driven functional verification closure of complex DUTs
7. Expertise in sequences and sequence libraries
8. Working knowledge of register package model, regressions tools like eManager and perl scripting.
9. Should have working knowledge of ARM based processors and AHB
Desirable skill set:
1. Exposure to other object oriented verification methodologies like VMM/OVM/UVM and system Verilog.
2. Exposure to C++, TLM and Co-verification
Role:
1. Ownership and leadership of verification activity .
2. Good coordination skills to work in a flexible manner with multi-skilled teams and schedule-critical projects
Technical interaction with concept, system, program and design teams that are geographically distributed
If you are interested please contact using this link
Cover Letter's, Resume's and Jobs
Cover letter gets the recipient to read your resume, the resume gets you an interview and the interview gets you the job offer.
iOS 5: Complete list of 200+ Features
If you are an Apple fan like i am, own an IOS device and are curious to know what the full list of features on the new IOS 5 are, then follow the hyperlink!
R.I.P: Steve Jobs (February 24, 1955 – October 5, 2011)
You defined how products should be made and brought to the masses. You re-iterated that successful technologies are which deliver and refine user experience.
IBM, Intel Start $4.4 Billion Chip Venture in New York
Kudos to IBM, Intel and New York state for putting together a deal that will make upstate New York the center of R&D work for chip production on 450-mm and the development of 22- and 14-nm process technology for IBM's so-called "fab club," the Common Platform Alliance. According to New York Governor Andrew Cuomo, the deal, which involves $4.4 billion of investment, will create about 4,400 jobs and help the region retain another 2,500. Many of those jobs might just have easily have ended up in Taiwan, South Korea, Abu Dhabi or elsewhere. The deal is a coup for New York, which is presumably offering the companies tax breaks or other incentives to locate the projects there. (New York state itself is kicking in some $400 million over five years, but Gov. Cuomo made it clear in a statement announcing the projects that no private company will receive any state funds as part of the agreement.) Albany, already home to the semiconductor research consortium Sematech, the Albany Nanotech Complex and, soon, the Global 450 Consortium, increasingly appears to have surpassed the Silicon Valley as the place to be for semiconductor industry R&D. [More]
Intel Medfield Atom based Android Tablet in 2012
Intel is one of few companies that was given access to the Google Android Honeycomb source code–which Google has to this date not made public yet because the company is still optimizing Honeycomb for future phone releases–and it took Intel a few weeks to re-compile the code to make it compatible for its x86 architecture–the code was originally written for ARM chipsets. "It is HOT" [More here]
The wireless generation dance - 1G, 2G, 2Gt, 3G, 3Gt, 4G
The worldwide communication technology thirst and demands in bringing digital information to widespread end users have pushed innovation to extremes. Each successive generation of cellular technology has been based on a new enabling technology. By new, i mean the availability of an existing technology at low cost, or, for handset designers, the availability of a technology sufficiently power efficient to be used in a portable device.
Too often we fail to learn from lessons of the past. As an industry, we have over 20 years of experience in designing cellular handsets and deploying cellular networks. The past tells us precisely what is and what is not possible in terms of future technology deployment. This allows us to detect when reality gaps occur. Reality gaps are those between technical practicality and wishful thinking. They happen all the time and can be particularly painful when technically complex systems are being deployed. Almost all technologies start with a reality gap. The technology fails to deliver as well as expected. Some technologies never close the gap and become failed technologies. Some people can make money from failed technologies, but the majority doesn’t. Failed technologies ultimately fail because they do not deliver user value. We also tend to forget that user expectations and customer expectations change over time. A technology has to be capable of sufficient dynamic range to be able to continue to improve as the technology and user expectations mature. Failed technologies often fail because they cannot close the reality gap and cannot catch up with changing user expectations. One example of a failed technology is WiMax!
Successful technologies are that which deliver along the whole industry value chain—device vendors, handset manufacturers, network manufacturers (software and hardware vendors), network operators, and end users. I aim to show in this article how different generations of wireless technology has been evolving to become a successful proposition, both technically and commercially. I hope you enjoy reading this article and hope to get your feedback.
The cellular wireless communications industry witnessed tremendous growth in the past decade with over four billion wireless subscribers worldwide. The first generation (1G) analog cellular systems supported voice communication with limited roaming. The second generation (2G) digital systems promised higher capacity and better voice quality than did their analog counterparts. Moreover, roaming became more prevalent thanks to fewer standards and common spectrum allocations across countries particularly in Europe.
The two widely deployed second-generation (2G) cellular systems are GSM (global system for mobile communications) and CDMA (code division multiple access). As for the 1G analog systems, 2G systems were primarily designed to support voice communication. In later releases of these standards, capabilities were introduced to support data transmission.
However, the data rates were generally lower than that supported by dial-up connections. The ITU-R initiative on IMT-2000 (international mobile Telecommunications 2000) paved the way for evolution to 3G. A set of requirements such as a peak data rate of 2 Mb/s and support for vehicular mobility were published under IMT-2000 initiative. Both the GSM and CDMA camps formed their own separate 3G partnership projects (3GPP and 3GPP2, respectively) to develop IMT-2000 compliant standards based on the CDMA technology. The 3G standard in 3GPP is referred to as wideband CDMA(WCDMA) because it uses a larger 5MHz bandwidth relative to 1.25MHz bandwidth used in 3GPP2’s cdma2000 system. The 3GPP2 also developed a 5MHz version supporting three 1.25MHz subcarriers referred to as cdma2000-3x. In order to differentiate from the 5MHz cdma2000-3x standard, the 1.25MHz system is referred to as cdma2000-1x or simply 3G-1x.
The first release of the 3G standards did not fulfill its promise of high-speed data transmissions as the data rates supported in practice were much lower than that claimed in the standards. A serious effort was then made to enhance the 3G systems for efficient data support. The 3GPP2 first introduced the HRPD (high rate packet data) system that used various advanced techniques optimized for data traffic such as channel sensitive scheduling, fast link adaptation and hybrid ARQ, etc. The HRPD system required a separate 1.25MHz carrier and supported no voice service. This was the reason that HRPD was initially referred to as cdma2000-1xEVDO (evolution data only) system. The 3GPP followed a similar path and introduced HSPA (high speed packet access) enhancement to the WCDMA system. The HSPA standard reused many of the same data-optimized techniques as the HRPD system.
A difference relative to HRPD, however, is that both voice and data can be carried on the same 5MHz carrier in HSPA. The voice and data traffic are code multiplexed in the downlink. In parallel to HRPD, 3GPP2 also developed a joint voice data standard that was referred to as cdma2000-1xEVDV (evolution data voice). Like HSPA, the cdma2000-1xEVDV system supported both voice and data on the same carrier but it was never commercialized. In the later release of HRPD, VoIP (Voice over Internet Protocol) capabilities were introduced to provide both voice and data service on the same carrier. The two 3G standards namely HSPA and HRPD were finally able to fulfill the 3G promise and have been widely deployed in major cellular markets to provide wireless data access.
A quick summary of the different generations!
First generation (1G).
AMPS/ETACS handsets in the 1980s required low-cost microcontrollers to manage the allocation of multiple RF (radio frequency) channels (833 × 30 kHz channels for AMPS, 1000 × 25 kHz channels for ETACS) and low-cost RF components that could provide acceptable performance at 800/900 MHz.
Second generation (2G). GSM, TDMA, and CDMA handsets in the 1990s required low-cost digital signal processors (DSPs) for voice codecs and related baseband processing tasks, and low-cost RF components that could provide acceptable performance at 800/900 MHz, 1800 MHz, and 1900 MHz.
Third generation (3G). W-CDMAand CDMA2000 handsets require—in addition to low-cost microcontrollers and DSPs—low-cost, low power budget CMOS or CCD image sensors; low-cost, low power budget image and video encoders; low-cost, low power budget memory; low-cost RF components that can provide acceptable performance at 1900/2100 MHz; and high-density battery technologies.
Beyond 3G systems While HSPA and HRPD systems were being developed and deployed, IEEE 802 LMSC (LAN/MAN Standard Committee) introduced the IEEE 802.16e standard for mobile broadband wireless access. This standard was introduced as an enhancement to an earlier IEEE 802.16 standard for fixed broadband wireless access. The 802.16e standard employed a different access technology named OFDMA (orthogonal frequency division multiple access) and claimed better data rates and spectral efficiency than that provided by HSPA and HRPD.
Although the IEEE 802.16 family of standards is officially called WirelessMAN in IEEE, it has been dubbedWiMAX (worldwide interoperability for microwave access) by an industry group named theWiMAX Forum. The mission of theWiMAX Forum is to promote and certify the compatibility and interoperability of broadband wireless access products. The WiMAX system supporting mobility as in IEEE 802.16e standard is referred to as MobileWiMAX. In addition to the radio technology advantage, MobileWiMAX also employed a simpler network architecture based on IP protocols.
The introduction of Mobile WiMAX led both 3GPP and 3GPP2 to develop their own version of beyond 3G systems based on the OFDMA technology and network architecture similar to that in MobileWiMAX. The beyond 3G system in 3GPP is called evolved universal terrestrial radio access (evolved UTRA) and is also widely referred to as LTE (Long-Term Evolution) while 3GPP2’s version is called UMB (ultra mobile broadband). It should be noted that all three beyond 3G systems namely Mobile WiMAX, LTE and UMB meet IMT-2000 requirements and hence they are also part of IMT-2000 family of standards.
Long-Term Evolution (LTE) The goal of LTE is to provide a high-data-rate, low-latency and packet-optimized radioaccess technology supporting flexible bandwidth deployments. In parallel, new network architecture is designed with the goal to support packet-switched traffic with seamless mobility, quality of service and minimal latency. The air-interface related attributes of the LTE system are summarized in Table 1.1. The system supports flexible bandwidths thanks to OFDMA and SC-FDMA access schemes. In addition to FDD (frequency division duplexing) and TDD (time division duplexing), halfduplex FDD is allowed to support low cost UEs. Unlike FDD, in half-duplex FDD operation a UE is not required to transmit and receive at the same time. This avoids the need for a costly duplexer in the UE. The system is primarily optimized for low speeds up to 15 km/h. However, the system specifications allow mobility support in excess of 350 km/h with some performance degradation. The uplink access is based on single carrier frequency division multiple access (SC-FDMA) that promises increased uplink coverage due to low peak-to-average power ratio (PAPR) relative to OFDMA. The system supports downlink peak data rates of 326 Mb/s with 4 × 4 MIMO (multiple input multiple output) within 20MHz bandwidth. Since uplink MIMO is not employed in the first release of the LTE standard, the uplink peak data rates are limited to 86 Mb/s within 20MHz bandwidth. In addition to peak data rate improvements, the LTE system provides two to four times higher cell spectral efficiency relative to the Release 6 HSPA system. Similar improvements are observed in cell-edge throughput while maintaining same-site locations as deployed for HSPA. In terms of latency, the LTE radio-interface and network provides capabilities for less than 10 ms latency for the transmission of a packet from the network to the UE.
Evolution to 4G The radio-interface attributes for Mobile WiMAX and UMB are very similar to those of LTE given in Table 1.1. All three systems support flexible bandwidths, FDD/TDD duplexing, OFDMA in the downlink and MIMO schemes. There are a few differences such as uplink in LTE is based on SC-FDMA compared to OFDMA in Mobile WiMAX and UMB. The performance of the three systems is therefore expected to be similar with small differences. Similar to the IMT-2000 initiative, ITU-R Working Party 5D has stated requirements for IMT-advanced systems. Among others, these requirements include average downlink data rates of 100 Mbit/s in the wide area network, and up to 1 Gbit/s for local access or lowmobility scenarios. Also, at the World Radiocommunication Conference 2007 (WRC-2007), a maximum of a 428MHz new spectrum is identified for IMT systems that also include a 136MHz spectrum allocated on a global basis. Both 3GPPand IEEE 802LMSCare actively developing their own standards for submission to IMT-advanced. The goal for both LTE-advanced and IEEE 802.16m standards is to further enhance system spectral efficiency and data rates while supporting backward compatibility with their respective earlier releases. As part of the LTE-advanced and IEEE 802.16 standards developments, several enhancements including support for a larger than 20MHz bandwidth and higher-order MIMO are being discussed to meet the IMT-advanced requirements.
1G
AMPS family - AMPS · TACS · ETACS
Other - NMT · Hicap · Mobitex · DataTAC
2G
GSM/3GPP family - GSM · CSD
3GPP2 family - cdmaOne (IS-95)
AMPS family - D-AMPS (IS-54 and IS-136)
Other - CDPD · iDEN · PDC · PHS
2G transitional (2.5G, 2.75G)
GSM/3GPP family - HSCSD · GPRS · EDGE/EGPRS
3GPP2 family - CDMA2000 1xRTT (IS-2000)
Other - WiDEN
3G (IMT-2000)
3GPP family - UMTS (UTRAN) · WCDMA-FDD · WCDMA-TDD · UTRA-TDD LCR (TD-SCDMA)
3GPP2 family - CDMA2000 1xEV-DO (IS-856)
3G transitional (3.5G, 3.75G, 3.9G)
3GPP family - HSPA · HSPA+ · LTE (E-UTRA)
3GPP2 family - EV-DO Rev. A · EV-DO Rev. B
IEEE family - Mobile WiMAX (IEEE 802.16e-2005) · Flash-OFDM · IEEE 802.20
4G (IMT-Advanced)
3GPP family - LTE Advanced
IEEE family - IEEE 802.16m
Too often we fail to learn from lessons of the past. As an industry, we have over 20 years of experience in designing cellular handsets and deploying cellular networks. The past tells us precisely what is and what is not possible in terms of future technology deployment. This allows us to detect when reality gaps occur. Reality gaps are those between technical practicality and wishful thinking. They happen all the time and can be particularly painful when technically complex systems are being deployed. Almost all technologies start with a reality gap. The technology fails to deliver as well as expected. Some technologies never close the gap and become failed technologies. Some people can make money from failed technologies, but the majority doesn’t. Failed technologies ultimately fail because they do not deliver user value. We also tend to forget that user expectations and customer expectations change over time. A technology has to be capable of sufficient dynamic range to be able to continue to improve as the technology and user expectations mature. Failed technologies often fail because they cannot close the reality gap and cannot catch up with changing user expectations. One example of a failed technology is WiMax!
Successful technologies are that which deliver along the whole industry value chain—device vendors, handset manufacturers, network manufacturers (software and hardware vendors), network operators, and end users. I aim to show in this article how different generations of wireless technology has been evolving to become a successful proposition, both technically and commercially. I hope you enjoy reading this article and hope to get your feedback.
The cellular wireless communications industry witnessed tremendous growth in the past decade with over four billion wireless subscribers worldwide. The first generation (1G) analog cellular systems supported voice communication with limited roaming. The second generation (2G) digital systems promised higher capacity and better voice quality than did their analog counterparts. Moreover, roaming became more prevalent thanks to fewer standards and common spectrum allocations across countries particularly in Europe.
The two widely deployed second-generation (2G) cellular systems are GSM (global system for mobile communications) and CDMA (code division multiple access). As for the 1G analog systems, 2G systems were primarily designed to support voice communication. In later releases of these standards, capabilities were introduced to support data transmission.
However, the data rates were generally lower than that supported by dial-up connections. The ITU-R initiative on IMT-2000 (international mobile Telecommunications 2000) paved the way for evolution to 3G. A set of requirements such as a peak data rate of 2 Mb/s and support for vehicular mobility were published under IMT-2000 initiative. Both the GSM and CDMA camps formed their own separate 3G partnership projects (3GPP and 3GPP2, respectively) to develop IMT-2000 compliant standards based on the CDMA technology. The 3G standard in 3GPP is referred to as wideband CDMA(WCDMA) because it uses a larger 5MHz bandwidth relative to 1.25MHz bandwidth used in 3GPP2’s cdma2000 system. The 3GPP2 also developed a 5MHz version supporting three 1.25MHz subcarriers referred to as cdma2000-3x. In order to differentiate from the 5MHz cdma2000-3x standard, the 1.25MHz system is referred to as cdma2000-1x or simply 3G-1x.
The first release of the 3G standards did not fulfill its promise of high-speed data transmissions as the data rates supported in practice were much lower than that claimed in the standards. A serious effort was then made to enhance the 3G systems for efficient data support. The 3GPP2 first introduced the HRPD (high rate packet data) system that used various advanced techniques optimized for data traffic such as channel sensitive scheduling, fast link adaptation and hybrid ARQ, etc. The HRPD system required a separate 1.25MHz carrier and supported no voice service. This was the reason that HRPD was initially referred to as cdma2000-1xEVDO (evolution data only) system. The 3GPP followed a similar path and introduced HSPA (high speed packet access) enhancement to the WCDMA system. The HSPA standard reused many of the same data-optimized techniques as the HRPD system.
A difference relative to HRPD, however, is that both voice and data can be carried on the same 5MHz carrier in HSPA. The voice and data traffic are code multiplexed in the downlink. In parallel to HRPD, 3GPP2 also developed a joint voice data standard that was referred to as cdma2000-1xEVDV (evolution data voice). Like HSPA, the cdma2000-1xEVDV system supported both voice and data on the same carrier but it was never commercialized. In the later release of HRPD, VoIP (Voice over Internet Protocol) capabilities were introduced to provide both voice and data service on the same carrier. The two 3G standards namely HSPA and HRPD were finally able to fulfill the 3G promise and have been widely deployed in major cellular markets to provide wireless data access.
A quick summary of the different generations!
First generation (1G).
AMPS/ETACS handsets in the 1980s required low-cost microcontrollers to manage the allocation of multiple RF (radio frequency) channels (833 × 30 kHz channels for AMPS, 1000 × 25 kHz channels for ETACS) and low-cost RF components that could provide acceptable performance at 800/900 MHz.
Second generation (2G). GSM, TDMA, and CDMA handsets in the 1990s required low-cost digital signal processors (DSPs) for voice codecs and related baseband processing tasks, and low-cost RF components that could provide acceptable performance at 800/900 MHz, 1800 MHz, and 1900 MHz.
Third generation (3G). W-CDMAand CDMA2000 handsets require—in addition to low-cost microcontrollers and DSPs—low-cost, low power budget CMOS or CCD image sensors; low-cost, low power budget image and video encoders; low-cost, low power budget memory; low-cost RF components that can provide acceptable performance at 1900/2100 MHz; and high-density battery technologies.
Beyond 3G systems While HSPA and HRPD systems were being developed and deployed, IEEE 802 LMSC (LAN/MAN Standard Committee) introduced the IEEE 802.16e standard for mobile broadband wireless access. This standard was introduced as an enhancement to an earlier IEEE 802.16 standard for fixed broadband wireless access. The 802.16e standard employed a different access technology named OFDMA (orthogonal frequency division multiple access) and claimed better data rates and spectral efficiency than that provided by HSPA and HRPD.
Although the IEEE 802.16 family of standards is officially called WirelessMAN in IEEE, it has been dubbedWiMAX (worldwide interoperability for microwave access) by an industry group named theWiMAX Forum. The mission of theWiMAX Forum is to promote and certify the compatibility and interoperability of broadband wireless access products. The WiMAX system supporting mobility as in IEEE 802.16e standard is referred to as MobileWiMAX. In addition to the radio technology advantage, MobileWiMAX also employed a simpler network architecture based on IP protocols.
The introduction of Mobile WiMAX led both 3GPP and 3GPP2 to develop their own version of beyond 3G systems based on the OFDMA technology and network architecture similar to that in MobileWiMAX. The beyond 3G system in 3GPP is called evolved universal terrestrial radio access (evolved UTRA) and is also widely referred to as LTE (Long-Term Evolution) while 3GPP2’s version is called UMB (ultra mobile broadband). It should be noted that all three beyond 3G systems namely Mobile WiMAX, LTE and UMB meet IMT-2000 requirements and hence they are also part of IMT-2000 family of standards.
Long-Term Evolution (LTE) The goal of LTE is to provide a high-data-rate, low-latency and packet-optimized radioaccess technology supporting flexible bandwidth deployments. In parallel, new network architecture is designed with the goal to support packet-switched traffic with seamless mobility, quality of service and minimal latency. The air-interface related attributes of the LTE system are summarized in Table 1.1. The system supports flexible bandwidths thanks to OFDMA and SC-FDMA access schemes. In addition to FDD (frequency division duplexing) and TDD (time division duplexing), halfduplex FDD is allowed to support low cost UEs. Unlike FDD, in half-duplex FDD operation a UE is not required to transmit and receive at the same time. This avoids the need for a costly duplexer in the UE. The system is primarily optimized for low speeds up to 15 km/h. However, the system specifications allow mobility support in excess of 350 km/h with some performance degradation. The uplink access is based on single carrier frequency division multiple access (SC-FDMA) that promises increased uplink coverage due to low peak-to-average power ratio (PAPR) relative to OFDMA. The system supports downlink peak data rates of 326 Mb/s with 4 × 4 MIMO (multiple input multiple output) within 20MHz bandwidth. Since uplink MIMO is not employed in the first release of the LTE standard, the uplink peak data rates are limited to 86 Mb/s within 20MHz bandwidth. In addition to peak data rate improvements, the LTE system provides two to four times higher cell spectral efficiency relative to the Release 6 HSPA system. Similar improvements are observed in cell-edge throughput while maintaining same-site locations as deployed for HSPA. In terms of latency, the LTE radio-interface and network provides capabilities for less than 10 ms latency for the transmission of a packet from the network to the UE.
Evolution to 4G The radio-interface attributes for Mobile WiMAX and UMB are very similar to those of LTE given in Table 1.1. All three systems support flexible bandwidths, FDD/TDD duplexing, OFDMA in the downlink and MIMO schemes. There are a few differences such as uplink in LTE is based on SC-FDMA compared to OFDMA in Mobile WiMAX and UMB. The performance of the three systems is therefore expected to be similar with small differences. Similar to the IMT-2000 initiative, ITU-R Working Party 5D has stated requirements for IMT-advanced systems. Among others, these requirements include average downlink data rates of 100 Mbit/s in the wide area network, and up to 1 Gbit/s for local access or lowmobility scenarios. Also, at the World Radiocommunication Conference 2007 (WRC-2007), a maximum of a 428MHz new spectrum is identified for IMT systems that also include a 136MHz spectrum allocated on a global basis. Both 3GPPand IEEE 802LMSCare actively developing their own standards for submission to IMT-advanced. The goal for both LTE-advanced and IEEE 802.16m standards is to further enhance system spectral efficiency and data rates while supporting backward compatibility with their respective earlier releases. As part of the LTE-advanced and IEEE 802.16 standards developments, several enhancements including support for a larger than 20MHz bandwidth and higher-order MIMO are being discussed to meet the IMT-advanced requirements.
1G
AMPS family - AMPS · TACS · ETACS
Other - NMT · Hicap · Mobitex · DataTAC
2G
GSM/3GPP family - GSM · CSD
3GPP2 family - cdmaOne (IS-95)
AMPS family - D-AMPS (IS-54 and IS-136)
Other - CDPD · iDEN · PDC · PHS
2G transitional (2.5G, 2.75G)
GSM/3GPP family - HSCSD · GPRS · EDGE/EGPRS
3GPP2 family - CDMA2000 1xRTT (IS-2000)
Other - WiDEN
3G (IMT-2000)
3GPP family - UMTS (UTRAN) · WCDMA-FDD · WCDMA-TDD · UTRA-TDD LCR (TD-SCDMA)
3GPP2 family - CDMA2000 1xEV-DO (IS-856)
3G transitional (3.5G, 3.75G, 3.9G)
3GPP family - HSPA · HSPA+ · LTE (E-UTRA)
3GPP2 family - EV-DO Rev. A · EV-DO Rev. B
IEEE family - Mobile WiMAX (IEEE 802.16e-2005) · Flash-OFDM · IEEE 802.20
4G (IMT-Advanced)
3GPP family - LTE Advanced
IEEE family - IEEE 802.16m
Openpicus releases new applications
openPICUS is an open source wireless platform that uses Wi-Fi and freeRTOS to connect things to the web. The guys from openpicus have released some new applications. One new feature is hibernation mode for lower energy use with battery-powered applications. The other new feature is integration with ThingSpeak.
All you have to do is download the ThingSpeak.com Library from openPICUS and use it with your FlyPort Wi-fi device. Now, you can use sensors connected to ThingSpeak for data logging, visualizations, and access to all of the ThingSpeak apps, such as ThingTweet and ThingHTTP. Here's the video...
All you have to do is download the ThingSpeak.com Library from openPICUS and use it with your FlyPort Wi-fi device. Now, you can use sensors connected to ThingSpeak for data logging, visualizations, and access to all of the ThingSpeak apps, such as ThingTweet and ThingHTTP. Here's the video...
Intelligent 4G basestations to be powered by Intel
The Inquirer reports that Ubiquisys has announced that it will develop WiFi base stations using Intel's processors. The intelligent base stations that Ubiquisys is developing are small cells for use in public spaces and big businesses. The need for Intel's processor comes from the growing need to have content within the principality of the base station rather than pulling everything off the internet.
EEWeb Site of the day - May 25, 2011
We are listed on EEWeb Site of the day - May 25, 2011. EEWeb is a premier electrical engineering community that strives to offer its members the best online resources for hardware designers. EEWeb is independently owned and operated by co-founders Cody Miller and Joe Wolin. The development of the site began in late 2007 and was released in late 2010. We have partnered with Digi-Key Corporation as an exclusive sponsor of EEWeb and we are proud to promote Digi-Key's first-class products and services.
Cyclic Redundancy Checking (CRC) - Part 3
Augmentation is a technique used to produce a null CRC result, while preserving both the original data and the CRC checksum. In communication systems using cyclic redundancy checking, it would be desirable to obtain a null CRC result for each transmission, as the simplified verification will help to speed up the data handling.
Traditionally, a null CRC result is generated by adding the cyclic redundancy
checksum to the data, and calculating the CRC on the new data. While this
simplifies the verification, it has the unfortunate side effect of changing the data. Any node receiving the data+CRC result will be able to verify that no corruption has occurred, but will be unable to extract the original data, because the checksum is not known. This can be overcome by transmitting the checksum
along with the modified data, but any data-handling advantage gained in the verification process is offset by the additional steps needed to recover the original data.
Augmentation allows the data to be transmitted along with its checksum, and still obtain a null CRC result. As explained before when obtain a null CRC result, the data changes, when the checksum is added. Augmentation avoids this by shifting the data left or augmenting it with a number of zeros, equivalent to the degree of the generator polynomial. When the CRC result for the shifted data is
added, both the original data and the checksum are preserved.
In this example, our generator polynomial (x3 + x2 + 1 or 1101) is of degree 3, so the data (0xD6B5) is shifted to the left by three places or augmented by three zeros.
0xD6B5 = 1101011010110101 becomes 0x6B5A8 = 1101011010110101000.
Note that the original data is still present within the augmented data.
0x6B5A8 = 1101011010110101000
Data = D6B5 Augmentation = 000
Calculating the CRC result for the augmented data (0x6B5A8) using our generator polynomial (1101), gives a remainder of 101 (degree 2). If we add this to the augmented data, we get:
0x6B5A8 + 0b101 = 1101011010110101000 + 101
= 1101011010110101101
= 0x6B5AD
As discussed before, calculating the cyclic redundancy checksum for 0x6B5AD will result in a null checksum, simplifying the verification. What is less apparent is that the original data is still preserved intact.
0x6B5AD = 1101011010110101101
Data = D6B5 CRC = 101
The degree of the remainder or cyclic redundancy checksum is always less than the degree of the generator polynomial. By augmenting the data with a number of zeros equivalent to the degree of the generator polynomial, we ensure that the addition of the checksum does not affect the augmented data.
In any communications system using cyclic redundancy checking, the same generator polynomial will be used by both transmitting and receiving nodes to generate checksums and verify data. As the receiving node knows the degree of the generator polynomial, it is a simple task for it to verify the transmission by calculating the checksum and testing for zero, and then extract the data by discarding the last three bits.
Thus augmentation preserves the data, while allowing a null cyclic redundancy checksum for faster verification and data handling.
Traditionally, a null CRC result is generated by adding the cyclic redundancy
checksum to the data, and calculating the CRC on the new data. While this
simplifies the verification, it has the unfortunate side effect of changing the data. Any node receiving the data+CRC result will be able to verify that no corruption has occurred, but will be unable to extract the original data, because the checksum is not known. This can be overcome by transmitting the checksum
along with the modified data, but any data-handling advantage gained in the verification process is offset by the additional steps needed to recover the original data.
Augmentation allows the data to be transmitted along with its checksum, and still obtain a null CRC result. As explained before when obtain a null CRC result, the data changes, when the checksum is added. Augmentation avoids this by shifting the data left or augmenting it with a number of zeros, equivalent to the degree of the generator polynomial. When the CRC result for the shifted data is
added, both the original data and the checksum are preserved.
In this example, our generator polynomial (x3 + x2 + 1 or 1101) is of degree 3, so the data (0xD6B5) is shifted to the left by three places or augmented by three zeros.
0xD6B5 = 1101011010110101 becomes 0x6B5A8 = 1101011010110101000.
Note that the original data is still present within the augmented data.
0x6B5A8 = 1101011010110101000
Data = D6B5 Augmentation = 000
Calculating the CRC result for the augmented data (0x6B5A8) using our generator polynomial (1101), gives a remainder of 101 (degree 2). If we add this to the augmented data, we get:
0x6B5A8 + 0b101 = 1101011010110101000 + 101
= 1101011010110101101
= 0x6B5AD
As discussed before, calculating the cyclic redundancy checksum for 0x6B5AD will result in a null checksum, simplifying the verification. What is less apparent is that the original data is still preserved intact.
0x6B5AD = 1101011010110101101
Data = D6B5 CRC = 101
The degree of the remainder or cyclic redundancy checksum is always less than the degree of the generator polynomial. By augmenting the data with a number of zeros equivalent to the degree of the generator polynomial, we ensure that the addition of the checksum does not affect the augmented data.
In any communications system using cyclic redundancy checking, the same generator polynomial will be used by both transmitting and receiving nodes to generate checksums and verify data. As the receiving node knows the degree of the generator polynomial, it is a simple task for it to verify the transmission by calculating the checksum and testing for zero, and then extract the data by discarding the last three bits.
Thus augmentation preserves the data, while allowing a null cyclic redundancy checksum for faster verification and data handling.
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Developing Silicon IP with Open Source Tools
The electronic design automation (EDA) tool industry is big business, and commercial licenses are extremely expensive. Open standards have driven many proprietary EDA technologies to be publicly released as free/libre open source software (F/LOSS) and some have become IEEE standards. In this article, author Arthur Low reviews the history of key advances in ICs and EDA tools. The common theme presented in this article for the driver of technology innovation is the requirement to develop the most advanced microprocessor possible. Today, a low-cost, high-value-added business model can efficiently serve the market for IC subsystems licensed as intellectual property (silicon IP) in the form of compilable source code. Alternatively, for larger SoC designs, engineering budgets can be shifted from the purchase of a relatively small number of high-cost EDA tool licenses to open source EDA technologies that can be run on massive compute-server farms. The two business models are not theoretical, but realistic. The author explains how his company (Crack Semiconductor) developed commercially successful cryptographic silicon IP using entirely open source EDA technologies and how another company (SiCortex) pushed the limits of IC design and open source EDA tools by simulating and verifying a massively parallel supercomputer.
Texas Instruments(TI) to buy National Semiconductor for $6.5 billion
The Wall Street Journal is reporting that TI intends to buy National Semiconductor for $6.5 billion, $25/share. These two semiconductor firms are analog semiconductor powerhouses with large businesses in non-analog markets as well. TI says that this move will immediately grow National’s sales team by 10x.
The article also states that TI has pulled out of the recession with a sharp rebound in orders while National Semi has not done as well. This apparently created a big acquisition opportunity for TI.
The bid's hefty premium casts light on a large but unglamorous semiconductor business—chips based on analog technology and used for such duties as amplifying radio signals in cellphones and managing power consumption in computers.
The article also states that TI has pulled out of the recession with a sharp rebound in orders while National Semi has not done as well. This apparently created a big acquisition opportunity for TI.
The bid's hefty premium casts light on a large but unglamorous semiconductor business—chips based on analog technology and used for such duties as amplifying radio signals in cellphones and managing power consumption in computers.
Study gives 4G data performance high marks
Handsets operating on 4G cellular networks offer significant improvement in data transfer performance compared to their 3G predecessors, according to a study evaluating the performance of smartphones available from U.S. national carriers conducted by consulting firm Metrico Wireless Inc. More Here.
ZTE claims 10-Tbps data transmission record
Chinese telecommunications equipment company ZTE Corp. claims to have broken the world record for a single-channel data transmission with a rate of 10 terabits per second over 640-kilometers of optical fiber. This is the equivalent of sending 160 high definition movies every second. More here.
Six ways to manage a side hustle without going insane
A side hustle is anything you are doing outside of your full-time job (like building a business or a blog around something you are passionate about), and often involves an entrepreneurial enterprise of some sort. In this article Jenny Blake shares some tips with you to help you keep things together during the exciting pursuit of what you love
