Zero-forcing transceiver design in the multi-user MIMO cognitive relay networks

The transceiver design in a cognitive radio networks is studied, where all nodes are deployed with multiple antennas. A primary point-to-point MIMO link is authorized to utilize the spectrum. Ignoring the secondary users, the primary transmitter and receiver are designed based on the traditional singular value decomposition method. The secondary users consist of multiple source-destination pairs, assisted by multiple two-hop non-regenerative relays. The transceivers of the secondary users are supposed to cancel the interferences from the secondary users to the primary receiver, the interferences from the primary transmitter to the secondary users, and the inter-secondary-user interferences, in order to guarantee the communication quality of both the primary and secondary users. Based on the zero-forcing method, the transceivers are designed to minimize the noise power amplified by the relays. It is shown that the proposed transceiver design algorithm outperform the existed algorithm.