Wireless access with blind collision-multiplicity detection and retransmission diversity for quasi-static channels

Wireless multiple-access protocols using retransmission diversity resolve packet collisions through source separation techniques. Retransmissions are applied to achieve the necessary diversity level to determine the collision multiplicity blindly, whose proper detection is essential for good resolution performance. The so-called network-assisted diversity multiple access (NDMA) employs the rank test (RT) method for blind multiplicity detection, but static channel parameters throughout the retransmissions and the tight control of the transmitter phase are required. In this paper, a superior blind collision multiplicity-detection technique is introduced by combining the minimum description length criterion and a variation of the RT method. Collision resolution is accomplished through independent component analysis (ICA). Unlike blind NDMA,the new protocol, named ICA-NDMA, works in quasi-static fading channels, and does not need any phase control. Extensive performance analyses corroborate the performance advantages offered by ICA-NDMA.