Burst reservation CDMA protocol for mixed services S-PCS

A novel reservation-based CDMA multi-access protocol is proposed and its applicability for real-time voice and non-real time data communications in the satellite environment is investigated. It is shown that despite the long round-trip delays associated with the satellite communications, the proposed protocol maintains inherent advantages of the reservation-based protocols. This is mainly achieved through the use of a simultaneous multi-reservation scheme, whereby a user terminal would not need to delay transmission of real-time services through not having to solely rely on reception of the acknowledgement message. As the proposed protocol is packet-based, data terminals with a wide range of capabilities can be easily integrated into the system. The proposed protocol is compared to the hybrid TDMA/CDMA proposal of FRAMES, a candidate UMTS access scheme. Results show increased flexibility and capacity over the latter under similar conditions