Dual-band retrodirective array with integrated reflection-type and phase conjugating array using synthesized transmission lines

A new integrated feeding network for dual-band retrodirective array (RDA) is discussed in this paper. The core building block is the dual-mode synthesized transmission line. Without applying active switches, the synthesized line makes the array feeding network identical to a reflection-type RDA in one band, but resemble a phase conjugating array (PCA) in the other band. With the phase conjugating array involved, modulated data can be injected into the network to fulfill information transmission between the interrogator and the RDA. A four-element dual-band retrodirective array is fabricated to experimentally validate the concept with bistatic radiation patterns.