Third-generation (3G) wireless networks have received much publicity in recent months because of their ability to move data at high speeds and their potential support of multimedia services. Reaching 3G is the next step in a progression that started with first-generation (1G) technology, which the original analog wireless services used. Most carriers currently use second-generation (2G) networks for voice services; 2G networks support wireless data, but such data is typically circuit-switched. Circuit-switched data networks require you to dial a phone number (typically to reach an ISP) to establish a dedicated data connection. The common term "2.5G" refers to enhanced 2G networks that let carriers support packet-switched data. Packet-switched data features always-on functionality, so you don't need to make a dedicated phone call and can share bandwidth with other users.
Most people misunderstand 3G wireless network migration and the promise of 3G technology. Many carriers and wireless technology companies define 3G as large bandwidth. This definition is true to some extent. 2G networks feature a 9.6Kbps to 20Kbps wireless data speed, 2.5G networks handle 20Kbps to 128Kbps, and 3G networks support up to 384Kbps. The often-misunderstood aspect of 3G networks is that all users connected to a base station share the bandwidth. For example, if 10 users are concurrently using applications on a 384Kbps 3G network, the usable bandwidth is approximately 30Kbps per user. Thus, I see 3G as a technology to support more users and not necessarily more bandwidth. Of course, 384Kbps will be available if you want it, but it will come at a high price. So, don't expect to be using that wireless videophone anytime soon. The truth is that most data applications don't need huge bandwidth, and the widespread availability of 2.5G wireless data services and packet-switched data features should lead to many innovative consumer and enterprise wireless data solutions that don't require 3G networks' bandwidth.
Currently, only Japanese carriers use 3G network technologies commercially, with public trials in Tokyo and other cities. I expect to see 3G technologies commercially available in the United States in late 2002 or 2003. Initial services will be costly and probably will offer limited coverage areas, but 3G networks will fully integrate wireless voice and data services, thus providing the best use of the electromagnetic spectrum. One challenge of implementing 3G networks is the availability of electromagnetic spectrum frequencies. All radio frequency (RF) wireless networks, including 3G networks, use more spectrum for higher data-transfer rates, so spectrum frequencies are at a premium. Although many spectrum auctions have occurred in Asia and Europe in recent years, few have taken place in the United States because the Federal Communications Commission (FCC) has limited the use and availability of spectrum frequencies. Most spectrum frequencies in the United States are used for military purposes, so before 3G can be a reality in the United States, we need to find more spectrum frequencies. More spectrum frequencies could come from the military's portion of the spectrum, the use of free spectrum (such as frequencies in the 2.4GHz range), or the reuse of spectrum previously or currently used for purposes such as analog systems. In the next Mobile & Wireless UPDATE, I'll continue to examine the hype and reality of 3G wireless networks.
Aerie Networks Acquires Ricochet
Aerie Networks recently purchased Ricochet, a wireless data service that owner Metricom shut down in August. Aerie is committed to restarting the service and has mentioned that service charges will be significantly lower than Metricom's charges. The Ricochet service features data speeds faster than 128Kbps in 12 major US cities; in Denver, I've been able to reach speeds as fast as 300Kbps. We'll have to wait and see whether the Ricochet service starts operating again; this service offers real bandwidth for PDA, laptop, and portable Web-surfing devices. Stay tuned.