Hurdles seen on road to wireless Internet
By Patrick Mannion
RICHARDSON, Texas Engineers have a long road to travel before they can deliver robust wireless Internet products, according to a panel discussion cosponsored by EE Times on Wednesday (June 28). Panelists from major OEMs including Alcatel, Ericsson, Nortel, Samsung and Philips identified a wide range of weak links in delivering robust Web services to mobile users.
"When we say 'wireless Internet,' you shouldn't imagine you will be surfing the Web on a cell phone anytime soon," said Keith Shank, director of strategic market and business development at Ericsson Inc.'s Wireless Communications Division (Richardson, Texas). Shank, along with several others on the panel, said text messaging will likely be the driving application for wireless Internet devices over the next 18 months.
The term wireless Internet is misleading, Shank added. He believes the more generic term "wireless applications" is more appropriate epitomizing the difficulty of identifying what's to come.
The good news is that the so-called air interface wars are over, Shank said. The bad news is designers have been left with multiple air interfaces they must now support. Thus, the big challenge designers face "should not be interconnecting at speed, but making it all connect," he said. Shank also emphasized the importance of connection robustness through the use of fallback techniques.
Janet Lind, vice president of mobility network solutions at Nortel Networks (Richardson), said bringing Internet Protocol (IP) to cellular handsets is problematic and may not happen for three to five years. While the protocol will be supported on basestations soon, its packet structure makes it too inefficient for the mobile device. "Does IP adapt to cellular needs," she asked, "or do we adapt to IP?"
Lind also said engineers need to focus on delivering higher bit rates and more capacity while eliminating latencies, to give users the response times they're demanding.
Several panelists agreed that thermal design of increasingly miniaturized, integrated handsets and basestations is a key issue. Basestation and handset cooling, for example, remains a major stumbling block, said Muzibul Khan, senior director of product management for wireless terminals at Samsung Telecommunications America Inc. (Dallas). He isolated power-amplifier efficiency as the culprit and sees the problem only getting worse with the move toward multimode phones and basestations.
Khan is wary of the drive to multimode phones to begin with, considering it a poor trade-off of cost vs. demand. The issue of cost vs. performance vs. functionality was a mantra Khan repeatedly applied to mobile design issues.
Looking to the future, Ericsson's Shank sees the arrival of flashcard-size basestations that will greatly reduce power requirements and deployment costs. He also sees software-defined radio, the Holy Grail of mobile communications, as on the horizon maybe two years out. While software-defined radio will enhance spectral use for basestations, he sees it being far too power-hungry for mobile devices.
Khan agreed with Shank, but re-emphasized the need for research in practical issues that would make the user experience more rewarding. For example, he sees the arrival soon of over-the-air phone activation, which would eliminate the inconvenience of having to dial into the service provider to enter the phone's ESN number.
Taking a ground-up view, Glen Robertson, senior engineer at Alcatel (Plano, Texas), pointed out that much had to be done at the board level. According to Robertson, "Laminates, materials capability, geometries, stacking and dielectric issues remain central to any realistic improvement in integration and signal integrity."
Robertson added that environmental issues, such as the elimination of lead from solder an on-going project in all areas of electronics manufacturing cannot be ignored. The low cost of lead-based solders helps keep the overall manufacturing cost at a reasonable level.
The call for better and cheaper laminates was echoed by Andy Kowalewski, a senior manager at the communications division of Philips Semiconductors (Sunnyvale, Calif.). Kowalewski said laminates and associated materials are key enablers of smaller, cheaper and faster devices. He also alluded to the serious issue of component shortages that has resulted from the proliferation of mobile devices. "There was a time when we could readily receive orders of tantalum capacitors now we can't get any," he said.