Cellular technology, which revolutionized wireless telephones in the 1980s, now promises to do the same for mobile computers in the 1990s.
Analysts predict that most notebook PC makers will offer wireless options by the third quarter of next year. Yet despite the promise, sending data over cellular networks still poses some daunting challenges in terms of product development, cost, reliability and standards.
Of the three main wireless technologies — infrared and radio frequency (RF) arc the other tow – cellular is the most similar to the land-line connections many notebook computer users use today, analysts noted.
“Right now, cellular has some advantages over the other types of wireless communications,” said David Mack, business development director at WorkGroup Technologies Inc, a market research firm. For example,
Cellular networks cover nearly the entire country in uniform frequencies, analysts said. RF networks, on the other hand, are not as well-established. However, despite its advantages over other wireless technologies, linking a notebook and a cellular phone today often means a tangle of equipment: a notebook, a phone, batteries and a separate interface unit to provide the necessary “handshake” connection, since cellular phones have no dial tone. To address the problem, IBM has announced a 10MHz 186-bascd 9075 PCradio, a 5-pound notebook with an integrated cellular modem and cellular phone capabilities.
Other haven’t gone as far. NEC Technologies Inc’s Cellular workstation bundles its UltraLitc notbook with a P200 cellular phone. AT&T Computer systems is developing a package that will include its Safari notebook, a cellular phone and a single “smart” cable to link them, said AT&T officials
In February, Microcom and Mitsubishi. International Corp plan to ship the Cellular Data Link, which combines a Mitsubishi cellular telephone with a Microcom cellular MNP Class 10 modem, according to official of both firms.
Toshiba America information Systems Inc, meanwhile, is shipping a US$359 T24D/X modem capable of both land 1 inc and cell ular connections, and officials at the company.
Sending data over cellular networks is aslo expensive. Even if users can afford the cost, there is no guarantee of a stable connection, because existing celluar networks use analog, rather than digital technology. Pauses in cclu-lar connections can garble data or cause the modem to tcrminiatc the transmission.
Transferring small, separate volumes of data is not as effective, however, because call setup takes upto 1 minute, said Ira Brosky, president of Datacomm Research Co.
“Cellular is optimized to carry voice, but it’s not yet there for data” said WorkGroup’s Mack.
- Neal Boudettc and Steven Loudermilk