Electronic Design

What's Hot Today: Portable Communications

Do-It-All Cell Phones Juggle Multitude Of Services

People love their portable communications devices, specifically their cell phone. Heading out the door, you pick up your wallet or purse, watch, car keys, and your cell phone. Other portable communications devices like laptops and PDAs with comm capability are also very popular, but nothing tops the cell phone as the ultimate ubiquitous personal communicator.

We like to keep in touch, mainly by voice, but also by e-mail. We are simply addicted. And while voice is now and always will be the killer app for cell phones, carriers and equipment manufacturers perpetually add new and improved functions and services. The cell phone is evolving from just a commodity wireless phone into a complete communications device, replete with consumer electronics like "entertainment-on-the-go" features.

The hot features in today's cell phones are bigger color screens, built-in cameras, and data services like e-mail or SMS. Another booming segment is the walkie-talkie capability pioneered by Nextel. Verizon and Sprint have followed suit, with others likely right behind. It's just one more faster and easier way to keep in touch.

Furthermore, e-mail phones such as the RIM BlackBerry and Palm Treo have become extremely popular for those who have a real e-mail need without the laptop. Finally, a key feature—maybe the most important feature—is style. Your phone must be "cool" so you'll look cool using it. The clamshell design is in right now because, I'm guessing here, it looks cool to flip it open or closed, Star Trek style.

On the design side, chip manufacturers are creating new smart-phone architectures to handle all of the new data services and multimedia features. Agere, Analog Devices, Freescale (formerly Motorola), Texas Instruments, and others possess advanced chip sets just waiting for the deluge of multimedia applications. Of course, we now have digital cameras, with some vendors offering high-end models featuring a built-in camcorder. Games are popular in Asia and elsewhere, and they're growing in the U.S. as interesting and affordable downloadable games become available.

Other cell-phone add-ins include MP3/ARC music players, which seem to be a natural fit. Several chip companies now have tiny TV tuners that will give you standard TV on your small screen. Even digital radios may be integrated, with DAB (Eureka 147 in Europe) and iBOC HD Radio here. And don't forget the E911 capability that all phones must have. With it, GPS or a triangulation scheme provides location information to 911 emergency services. In turn, this will make other location services possible. Just having a GPS receiver built into your cell phone is a good idea for personal location, tracking, and navigation.

Some surveys predict a huge increase in the use of cell phones for machine-to-machine (M2M) applications. Here, the cell phone or a portion thereof is customized to some specific data-monitoring and/or control function. It can be used for remote control, sensor or meter reading, security services, and an enormous variety of other telemetry and control functions.

Designers must face the fact that not only will they need bigger batteries and improved power management, they also will need more computing power and especially lots of RAM. And, hard drives are not out of the question. The tiny 1-, 2-, and 4-Gbyte hard drives in Apple's iPod audio players could easily fit into a cell phone. With a hard drive, a BlackBerry-like keyboard, and Microsoft's new Mobile Windows operating system, will we see a handheld PC inside our cell phones? It's possible. Or, perhaps, will a cell-phone TiVo come along?

Right now, designers are working to incorporate the newer system-on-a-chip smart-phone architecture chips into the phones and work out the internal communications problems between the baseband modem, embedded processor, and multimedia processors. The ultimate solution for the handset obviously lies in a software-defined-radio (SDR) architecture, where any new technology or standard may be accommodated with a software download. This is the trend now for basestations. However, handsets won't be far behind, because they will provide worldwide and national roaming as well as full interoperability for data services.

Designers should note that one essential requirement for these up and coming multifunction phones is ease of use. Long button-pushing procedures, extensive menu selections, and 100-page manuals will turn users off and could make the related multimedia services unprofitable. Make it simple.

Finally, some vendors are also experimenting with Wi-Fi in cell phones. Having an 802.11b/g link in your cell phone gives you e-mail and Internet access via your company wireless local-area network or through the growing number of public access points (APs), or "hot spots." Hot-spot vendors are continuing to roll out new APs, as well as making roaming deals with multiple carriers, which will ultimately give you full access almost anywhere. Of course, with Wi-Fi you can also implement voice-over-IP (VoIP). The Wi-Fi capability could help with extra-fast downloads, while the VoIP-enabled handset could serve as your cordless company telephone via the Wi-Fi enterprise network.

As for 3G, it's here already. Like a great deal of technology, it sneaks up on you. Real wideband CDMA 3G is fully operational in parts of Europe, Japan, and Korea. Qualcomm's cdma2000, a real 3G option, is expanding throughout the U.S.

With Verizon and others adopting the latest versions of cdma2000, such as EV-DO and EV-DV, subscribers are beginning to experience the data services at 3G rates. Right now, it looks as though 3G in the U.S. is cdma2000, and 3G's future seems to be improved versions of this technology. The envisioned path from GSM-GPRS-EDGE-WCDMA isn't happening yet. GSM-GPRS-EDGE systems are rolling out, giving subscribers near-3G performance. We'll need to see a solution to the U.S. spectrum problem before WCDMA 3G comes on board. Unlike Europe with its GSM focus, the U.S. still supports the older TDMA along with GSM-GPRS-EDGE, in addition to IS-95 CDMA as well as cdma2000. Due to the multiple standards, unique data services for each, and total lack of interoperability, it's no wonder 3G is lagging in the U.S.

On another technology front, look out for the all-in-one cell phone. Some models will focus on business productivity, while others will be consumer entertainment toys. Lots of the features described here are already available, and many more will emerge at the end of this year and going into 2005. The handset will be your electronic Swiss army knife. Just start getting used to the small screen, despite the trend toward huge screens at home.

For those who need more than a cell phone for portable communications, namely a laptop, the answer is 802.11. It's in place now in many enterprises, with new hot spots popping up at a frenzied pace. As the carriers boost network speeds to 802.11g, and eventually 802.11n speed levels, its usefulness will continue to expand. Eventually, you'll have broadband features not even considered to this point, such as TV, video conferencing, video clips, music, news, and sports. Of course, VoIP will be available from some carriers. You will probably use a Bluetooth headset with your laptop to make phone calls concurrently with Internet access or e-mail.

On the other hand, Wi-Fi offers no panacea. Despite the hot-spot boom, many dead zones still exist. Plus, you often have to pay two or more carriers to get the required full coverage while traveling, making for an expensive proposition. Once more, data services supported by 3G technology are available. But a better choice may be a cell-phone wireless access card for your laptop. And who can tell what impact the new broadband wireless services will offer? Based upon the new IEEE 802.16 standard, 70-Mbit/s data rates will be available at a range up to 30 miles. Will we see that in cell phones too?

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