Passive Receiver Array Illuminated by a Near-Field Local Oscillator

Integrability and modularity of multiple functions present key features for future Artificial Intelligence (AI)-driven wireless systems. In this letter, a cooperatively operating architecture of two highly integrated building blocks is proposed and studied as a multifunction receiving array system. One module is a hybrid array for two joint operations, namely simultaneously radiating external local oscillator (LO) source and refocusing unknown RF signal. The other is a receiving plane that captures the wireless LO power and RF signal for demodulation with unified circuit-antenna passive receiver units. The proposed receiver presents the following attractive characteristics: physical feeding network for LO is replaced by the external LO wave source; demodulator for each receiving channel is self-consistently integrated into the unified mixing antenna units. This passive receiver array system is prototyped and verified with an external LO frequency of 21 GHz and an RF frequency of 19 GHz. The measured results exhibit a robust receiving intermediate frequency signal at 2 GHz, which validates the feasibility of the proposed architecture.