Collision resolution in packet radio networks using rotational invariance techniques

This paper deals with the multiple medium access problem in the packet radio environment. Under the framework of Network-assisted Diversity Multiple Access (NDMA), a recently proposed multiple access method, rotational invariance and PARAllel FACtor (PARAFAC) analysis signal processing tools are employed for blind collision resolution. The proposed approach (dubbed B-NDMA for Blind NDMA) overcomes the difficulty of orthogonal identification codes required by the original protocol, thereby improving channel utilization and system capacity, while being insensitive to multipath effects and synchronization errors. Performance issues are addressed both analytically and numerically.