pf_02929 - Laserfiche WebLink

Home

DRAFT 2.0 04/30/97 J..~hursheed Khan St. Paul, Minnesota the general idea of demodulation of the frames of the digital transmission still hold. Demodulation in a CDMA system has already been discussed. It is appropriate at this time to briefly mention the technologies used by various other providers in the Minneapolis - St. Paul greater metropolitan area. Sprint PCS and US WEST Communications Wireless both use CDMA technology in the PCS band; APT uses GSM (a fonn ofTDMA first developed in Europe), also in the PCS band; Airtouch uses CDMAlFDMA in the Cellular band; Nextel (providing mainly paging and two way radio services) uses FDMA(analog) / TDMA(digital) in the cellular band; AT&T uses FDMAffDMA in the cellular band. After having discussed the system level aspects of the various wireless communications technologies albeit from a very high level perspective, it is appropriate that we briefly focus on the benefits of using CDMA technology which is used to implement US WEST's wireless communications system. Among the many outstanding benefits of using a CDMA network the main advantages are the system's: . Increased capacity - The increase in capacity in a wide-band CDMA system is anywhere from 6 to 10 times that of a comparable analog system. It is also robust in various fading environments. Furthennore since everyone talks on the same frequency band (see figure) communication is susceptible to any sort of interference. That is why the system cannot be planned appropriately around widely varying cell heights. Additionally, once the cell site antenna centerline clears surrounding trees/clutter by approximately 20 ft, going at a greater height does not substantially improve overall system perfonnance (which is degraded by foliage and building clutter). . Superior voice quality - This is a feature of the particular wide-band digital technology being employed. . Integrated multiple classes of service - Besides carrying voice conversations the network is able to provide all other benefits related to various types of data transmission. Additionally, US WEST's unique presence in the greater metropolitan area will enable it to provide ubiquitous wireless service anywhere in the service area by integrating the land-line and the wireless network. In essence, consumers can reap the full benefits of a Wireless Local Area Network (W-LAN) as soon as the integration of the land lines to the wireless network takes effect. . Flexible architecture - Moreover, because of the flexible architecture of the design the evolution 6