Showing posts with label CDMA. Show all posts
Showing posts with label CDMA. Show all posts

Tuesday, July 26, 2011

4G Wireless Broadband Options

Wireless broadband is on an upward path to take over many of the applications that have long been the domain of wireline technologies. Wireless has the convenience of portability and mobility. What’s held back deployment and more powerful applications is the limited availability and speed of wireless connections. The move to 4G wireless looks to be a potential solution.

Wireless towers deliver 3G and 4G broadband for mobile and fixed applications...4G or fourth generation wireless doesn’t have a strict definition, but it is roughly stated as the bandwidth typical of Cable broadband or Ethernet over Copper business connections. With this level of transmission speed and a city-wide reach, 4G wireless can take over service for desktop as well as mobile devices.

One might throw WiFi into the 4G category. The bandwidth for a, b, g, and n WiFi technologies fall into the right bandwidth category. However, WiFi is a short distance system. It works well within and nearby particular locations, such as homes, offices, restaurants, hotels, airports and even park benches. But you can’t get in your car and drive away with a WiFi connection. It will disappear as soon as you leave the parking lot. In a way, WiFi is more of a PAN or Personal Area Network like Bluetooth.

The higher power wireless technologies, including 2G & 3G are associated with cellular phone service. These are based on using networks of fixed transmitters and receivers arranged as cells with signals that fill-in the coverage between towers. The trick of turning this system into a metropolitan or wide area network is to coordinate the handoff of an existing wireless connection as the user moves from cell to cell.

The most popular wireless technology right now is 3G. It offers bandwidths similar to T1 lines and basic DSL of around 1.5 Mbps on average in metropolitan areas. You may get two or more times this speed if you happen to be near a tower with few users. This is more than adequate for many mobile uses, such as Web browsing, email and viewing video clips on smartphone screens.

Beyond limited speed, 3G also suffers from limited bandwidth availability. It shares channels with cellular telephone on the same towers. Those channels were originally sized to support expected voice traffic. They’ve been overwhelmed by the higher bandwidth requirements of Internet data traffic. That’s why carriers are so insistent on bandwidth caps.

There are a couple of different approaches to 4G wireless. The one taken by the cell phone companies is to view 4G as an upgrade to their 3G systems. There are two differing cellular system that co-exist. One is a US-centric system called CDMA that is used by Verizon, Sprint and others. The other is a more global standard called GSM that is used by AT&T and T-Mobile.

Right now, AT&T and T-Mobile have upgraded their 3G networks to a faster version of the same thing called HSPA+ that delivers up to 6 to 8 Mbps. Verizon has moved to a 4G technology called LTE that offers downloads of 5 to 12 Mbps. Sprint has gone with another 4G technology called WiMAX that delivers downloads in the 3 to 6 Mbps speed range.

As wireless continues to evolve, 4G is expected to move into two camps. LTE is the technology most discussed as a truly universal standard. WiMAX deployment actually predated LTE and has installations worldwide. Both LTE and WiMAX have technical upgrade paths that can boost download speeds to over 100 Mbps and even 1000 Mbps. This is competitive with many fiber services and ensures that 4G wireless will be with us for a long time.

One thing we’re also seeing with 4G wireless is the use of lower frequency bands that can more easily penetrate buildings. These bands came from the re-deployment of those channels from UHF TV as part of a federal auction. Clear offers 4G fixed and mobile wireless service with a telephone option over WiMAX in over 80 cities nationwide. Right now, this service offers unlimited broadband service.



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Friday, May 13, 2011

DROID 2 Global is a World Phone

What would you call a smartphone with a 1.2 GHz processor that can make and receive calls from over 200 countries? You’d call it the DROID 2 Global.

DROID 2 Global for Verizon. Click for discount pricing.Just a second. This is a phone for Verizon and yet it works worldwide? How to they do that?

Verizon has excellent coverage in the United States and is the preferred carrier for tens of millions of users. The one little hiccup is that most of the world operates on the GSM standard and Verizon works on CDMA. It’s pretty much a VHS/Betamax argument. The two standards are mutually incompatible. So how does a Verizon phone work overseas?

Ah, the trick is to make it two phones in one. The Motorola DROID 2 has built in support for multiple networks. It covers WCDMA 850/1900/2100, CDMA 800/1900, GSM 850/900/1800/1900, HSDPA 10.2 Mbps (Category 9/10), CDMA EV-DO Release A, EDGE Class 12, GPRS Class 12, and HSUPA 1.8 Mbps. That’s pretty much everything you can use for telephone calls, Internet access and messaging.

Your DROID 2 comes with CDMA international roaming, but you’ll need to activate a pre-installed SIM card and a Global Service plan or feature to enable roaming outside of the US when using GSM and UTMS networks. You’ll want a global data plan so you can message and access the Web in those 200 countries, with 3G speeds in 125 countries. Why, it’s all the comfort of home!

Oh, by the way. The GSM feature doesn’t work on AT&T or T-Mobile networks here in the States. Verizon isn’t about to have any part of that.

Multiple network access may be the future of cell phones, at least in the near term. The idea of multiple incompatible networks is an idea who’s time has come and gone. Technology has advanced to the point where you can have both CDMA and GSM access designed into the same device. Look for this idea to spread to tablets and other 3G/4G devices.

The way things are going, it looks like most 4G wireless data networks are going to be LTE in a few years. Yet, WiMAX is enjoying popularity too. Next we need LTE/WiMAX dual-mode transceivers for smartphones and computing devices.

What other tricks does the DROID 2 Global have up its sleeve? A slide-out QWERTY keyboard for one. That makes high speed messaging and email a lot easier. The camera is a 5 Megapixel model with a dual LED flash and DVD-D1 video capture.

You also have the ability to make your DROID 2 Global a 3G mobile hotspot so you can share your data connection with up to 5 other devices.

This is truly a breakthrough smartphone design with a lot of advanced features for the Android user. Did you catch the 1.2 GHz processor? That should make your apps scream!

Are you interested in owning a cutting-edge phone with international capability? If so, learn more and order your Motorola DROID 2 Global for Verizon Wireless now. You can also browse the extensive selection of Android and other smartphones and feature phones, all at significant discounts and some even free.



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Wednesday, May 13, 2009

I'm Not Paying For That Aircard

Office wireline business Internet connections offer fast and reliable broadband service... as long as you stay in one place. For mobile operation you need to hunt down WiFi hotspots or get a wide area wireless service, such as cellular broadband. But very few laptop and notebook computers have the communications interface for cellular broadband built-in.

What you need is a carrier specific interface called an aircard. Sounds expensive, right? Well, they can be but not if you know where to look. What you want is the best free aircard you can get that will work with your particular computer. Fortunately, there are lots of choices available.

An aircard, sometimes called a wireless modem, is not all that different from a plug-in WiFi access card. A few years ago, laptop computers came with built-in telephone modems as their communications solution. If you wanted to connect with a WiFi router or wireless access device, you needed to buy a special card. Most often these plugged into the PCMCIA port on the side of the computer.

Nowadays, nearly all portable computers come with WiFi capability built-in and only some still offer telephone modems. But WiFi is only good within a few hundred foot radius of the connection point. If you want to travel around town, cross country or have broadband service available in a client's place of business, you need a wider ranging wireless Internet service. The best option right now is usually cellular broadband.

Cellular broadband is exactly what it sounds like. Every cell tower transmits both voice and data channels. The voice channels are used to carry cellular telephone calls. The data channels carry broadband Internet service to cell phones and other devices that can access them. A cell phone doesn't need an aircard since the data access circuitry is built-in. All it needs is a data service plan in addition to the usual voice service plan.

A notebook computer needs both the aircard interface and the data service plan for the carrier you want to use. That's another difference between WiFi and cellular broadband. WiFi is more standardized and compatible. Cellular systems generally fall into two distinct technologies. GSM is the worldwide standard and the one used by AT&T and T-Mobile. CDMA is popular in the United States and is used by Sprint-Nextel, Verizon and Alltel.

GSM standards include the 2.5G standard called EDGE and the 3G standard called HSPA. There's also a fallback to an earlier standard called GPRS. CDMA carriers support EV-DO as the 2.5G standard and EV-DO Rev A for 3G. Sprint and Clearwire are starting to deploy a 4G standard called WiMAX, but it is only available in a few places right now. Verizon and AT&T have stated they'll both be using another 4G standard called LTE, with build-outs just starting later this year.

If you want cellular broadband service right now, it's available with speeds that rival DSL, T1 lines, and Cable broadband service in most medium and larger cities. Farther out, you may have to settle for the slower 2.5G services or even dial-up level performance in some rural areas. If you can get solid cell phone service, you can probably get at least some wireless Internet connectivity. It's best to check the coverage maps for the carrier you are interested in to get a better idea of what speeds you can expect.

The other decision you need to make is how to connect the aircard to your computer. Some PCMCIA cards are still available. Newer interfaces include ExpressCard/34 and USB. Nearly all computers now have USB connectors, so that is the most universal interface.

So, where can you get a free aircard that works with your computer? Right now, there are just under a dozen different models available for the major carries. They're all the same price... free... so your decision will be based on size, connector, carrier of choice, Mac or Apple compatibility, and other features that include things like built-in memory card slots. Check the selection of free aircards now. Be sure to click on the features of each card you are interested in to get a summary of the specs. You can also compare multiple aircards side by side. When you find the one you want, click on the order button for more details on the aircard and data service plan. It's that easy to get mobile Internet access for your business or personal needs.



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Thursday, February 26, 2009

4G Wireless Broadband Wars This Year

Later this year, the battle for 4G domination will begin in earnest.

4G? Has 3G really finished deployment yet? Actually, 3G wireless networks are pretty well out there. The big players, AT&T, Verizon and Sprint, have upgraded most of their tower sites in populous areas. Many 3G smartphones and wireless modem aircards are available. While user awareness and adoption of 3G is still early on the learning curve, there's seemingly no time to waste for the carriers. It's on to 4G!

What's the big hurry? Part of it is an increasing sophistication in mobile applications with a corresponding increase in bandwidth demand. Some is good old fashioned competition. Think of it something like the space race or the building of the transcontinental railroad. The real value of these 4G networks is less about what's absolutely needed now and what they will enable in the future.

The 3G competition is based on two competing incompatible standards. The CDMA networks of Verizon, Alltel, and Sprint have developed EVDO technology. GSM networks, including AT&T, T-Mobile and foreign carriers have developed UMTS broadband, notably EDGE and HSPA.

The 4G competition is also dividing along two lines. First out of the gate is WiMAX, a worldwide standard for fixed and mobile broadband. But building steam is LTE, which is oddly enough being embraced by both Verizon and AT&T. Who's pushing WiMAX? Sprint and a fixed wireless player, Clearwire.

Is this going to be something like the ongoing DTV transition where one technology goes dark and the other immediately takes its place? No, not really. Both 3G and 4G will co-exist for a long time to come. WiMAX is being deployed in the 2.5 GHz band using the combined channel licenses owned by Sprint and Clearwire. Verizon and AT&T will use 700 MHz spectrum acquired in the recent telecom auction that was formerly the domain of analog TV broadcasting. That allows 3G cellular broadband to continue on the existing cellular bands as long as it makes economical sense.

One question is how much additional bandwidth we'll get from 4G wireless. During the run-up to the WiMAX standards approval, it was widely touted that a single WiMAX tower would have a range of something like 30 miles with bandwidth anywhere from 30 to 70 Mbps near the transmitter. In practice, Sprint was offering 2 to 4 Mbps download speeds on its Xohm service in Baltimore. The Xohm name has been retired, as Clearwire is taking over management of the combined Sprint and Clearwire channels. Clearwire has upped that to 4 to 6 Mbps on its Clear (tm) 4G wireless service for Portland, OR.

LTE hasn't been deployed yet, but peak data rates of 60 to 80 Mbps have been observed in tests. Verizon has suggested that average LTE data rates of around 8 Mbps are likely in actual service, although that may be conservative. Since there is a tradeoff between bandwidth, number of users per transmitter and distance from the tower, it seems likely that both LTE and WiMAX could be scaled up to provide speedier service as customer demand and the competitive environment dictate.

WiMAX has a lead in the race to the 4G wireless marketplace, with systems already in commercial service. Verizon's LTE has an advantage of frequencies lower in the electromagnetic spectrum, which should translate into greater ability to penetrate into buildings. Verizon expects to have 2 markets served by LTE by the end of this year. In 2010, Verizon expects to launch around 25 to 30 markets with LTE service. WiMAX will likely have a similar service level. There are now 50 markets in the U.S. and Europe with a pre-market version of WiMAX service.

4G wireless will likely reach a tipping point in 2011 or 2012, depending on the economy. Both mobile and fixed location services will be available, offering competition to DSL and Cable modem service as well as powering smartphones and netbooks. What will all this bandwidth be used for? You can bet that video will be the proverbial "killer-app", along with cloud computing and interactive everything.



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