Personal Access Communications System: fixed wireless local loop and mobile configurations and services

Introduction to WLL: Digital Service Technologies

“…call waiting, call forwarding, conference-calling, calling number identification, etc.). In addition, as in the wired systems, the features such as custom calling features, Centrex features can be supported by the switch [4,6]. If the air-interface provides a transparent channel to the switch, these service features depend totally on the switch functions.…”

“…As mentioned above, in WLL systems, the antennas for BTS and FSU can be arranged by line-of-sight and this reduces interference from the other user. So, the CDMA WLL cell can be designed with six or more sectors [6]. This increases the frequency efficiency and the system capacity.…”

“…Since WLL is a fixed service, high-gain directional antennas can be used between FSU and the base station, being arranged by line-of-sight (at least, nearly). Thus, WLL signal channel is a Gaussian noise channel or strong Rician channel (not a Rayleigh fading channel) [6]. This increases drastically the channel efficiency and the capacity of the system.…”

Current and future services using wireless local loop (WLL) systems

“…[8,10] PACS [11] is a hybrid standard of Bellcore's wireless access communications system (WACS) and Japanese PHS. We also review a wideband CDMA system recently commercialized.…”