Improved dual six-port receiver structure for two-dimensional Direction of Arrival detection using pHEMT power detectors

Two-dimensional Direction Of Arrival detection (DOA) of an arbitrary electromagnetic wave is a challenging task, especially if high accuracy has to be performed. The proposed DOA receiver is based on a phase detector using the interferometric Six-Port principle. For the proposed system an improved power detector concept using a High Electron Mobility Transistor has been developed featuring strictly square law behaviour to at least -15 dBm. Thus, the system offers a high dynamic range of more than 40 dB. The hereby presented system concept additionally has a switched delay line phase shifter for frequency estimation of the incoming electromagnetic wave. Moreover, the most important system components have been validated by measurements.