Performance issues and algorithms for dynamic channel assignment

Performance issues and algorithms for dynamic channel assignment (DCA) in a time division multiple access (TDMA) portable radio system are considered. With DCA, a radio port can use any carrier frequency in any available time-slot to set up a radio link with a portable. The portable selects a radio port prior to channel assignment for initial access or link transfer. Port and portable together determine the proper combination of time-slot and carrier frequency. Once established, a radio link remains unchanged until a call is completed or a link transfer occurs. Some limitations of DCA, such as difficulty in providing beacon signals, blind slots, frequency switching speed requirements, assignment delay and failures, and synchronization requirements, diminish its perceived advantages. Since uplink and downlink radio channels experience different interferences, asymmetric performance can occur. An algorithm that improves the balance of two-way performance is proposed. However, performance trade-offs inherent in DCA limitations still need to be addressed