Cooperative spatial multiplexing in mobile ad hoc networks

Abstract

We propose a new cooperative relaying technique for delivering high-rate data in mobile ad hoc networks. The proposed approach is to make each relay node to detect only a subset (called sub-stream) of the source data stream and all relay nodes to forward their low rate sub-streams simultaneously over the same physical channel. At the destination, multiple receive antennas or RAKE fingers separate the sub-streams and reassemble them based on their spatial characteristics or spreading codes, respectively. The distinctive benefit of this approach is the reduction of transmit and receive processing requirements on each relay node, while providing significant savings in the overall transmit and receive energy, particularly in the high spectral efficiency regime. Therefore, the proposed approach is particularly attractive in situations where each relay can handle only low-rates due to limited resources in terms of energy, bandwidth, hardware, and space (size). The proposed relaying architecture also provides an additional physical layer security mechanism