Using DQRAP (Distributed Queueing Random Access Protocol) for Local Wireless Communications

Establishing voice circuits by transmitting voice packets, i.e., transmitting only when there is sound, has been studied for some 30 years. Despite the theoretical efficiency few such systems have been implemented, possibly because of the inadequacy of available multiple access protocols. A new protocol, DQRAP (Distributed Queueing Random Access Protocol), developed by Xu and Campbell at the Illinois Institute of Technology offers a level of performance which could make voice packet systems feasible. A model of a DQRAP-based voice packet system is presented along with results of simulation studies. The DQRAP simulation results are compared with simulation results of a PRMA (Packet Reservation Multiple Access) voice packet system. It is shown that under identical conditions and assuming a 32 Kbps source, DQRAP drops less packets than PRMA at all offered loads and supports close to two conversations per channel as compared to 1.6 conversations per channel supported by PRMA. A brief description of the DQRAP algorithm is included.