PACS: personal access communications systems an alternative technology for PCS

The personal access communications system (PACS) is an American National Standards Institute common air interface standard developed for the 1.9 GHz PCS band in the United States. The PACS uses frequency division duplexing technology and is optimized to support low-mobility pedestrian outdoor usage and wireless local loop applications in a medium-range environment. PACS-Unlicensed B (PACS-UB) is a version of PACS using time division duplexing. The PACS-UB has been optimized for private, indoor wireless PBX applications and cordless telephony. Both modes of operation are supported using the same portable hardware and the same signaling protocol.