The authors design a transceiver for a multiuser (MU) multiple-input multiple-output communication system with a fullduplex relay (FDR) station. Such a system contains several types of interference, such as MU interference, parallel streams, and self-interference. To cancel this interference and achieve reliable MU communication, the authors use an equivalent FDR station model, in which the block diagonalisation (BD) scheme, which includes a base station, a relay, and a mobile station, can be used to derive the linear precoders and postprocessing filter. This work also studies link quality enhancement for the full-link system, including MU direct link and relay links communications. More interference will exist in a full-link system. They proposed a novel separable precoder and postprocessing algorithms to cancel all interference over the downlink FDR system. Simulation results demonstrate that the proposed transceiver design can provide a reliable sum rate with linear growth performance under the MU scenario with multiple interference and channel estimation errors and obtain diversity gain to improve the full system link quality.