Active Phase Conjugation with Multiple Antenna Array Element

In this paper we analyze the temporal and spatial compression characteristics of retrodirective antenna systems wherein active phase conjugation (APC) is deployed. It is shown that under the active phase conjugation Hermitian channel matrix properties result and these lead to opportunities for both temporal and spatial signal compression. The effects of additive channel noise, as well as compression assistance given by multipath richness are described. Some general properties of retrodirective antenna systems with respect to linear and circular polarized pilot signals are also discussed. The scheme elaborated here is compliant with a generic channel model and can therefore be easily incorporated into any readily available communication systems analysis or channel modelling software. The work presented in this paper provides a theoretical foundation for the previous experimental findings in APC systems.