Joint Multiband Linear Interferometric Receiver for Integrated Microwave and Terahertz Sensing and Communication Systems

Integrating microwave (MW) and terahertz (THz) operations and technologies is a promising solution in support of future multifunction and multistandard wireless systems such as joint sensing and communication platforms. However, the coexistence of MW and THz in a single receiver is a challenge to accommodate such a dual-band scheme of large frequency ratio and to satisfy its stringent performance requirements. To address these issues, a joint dual-band receiver is proposed and demonstrated for simultaneous MW and THz operations in this work. The proposed receiver inherits the advantages of conventional multiport linear interferometric architecture such as simple configuration and low-power consumption. MW and THz signals at individual frequency channels are concurrently received by a single hardware platform, then both signals are translated or converted to the intermediate frequency (IF) bands. The operating mechanism of the proposed receiver is studied and explained in detail. To verify the proposed architecture, an experimental prototype is realized and measured. Various M-quadrature-amplitude modulation (QAM) signals are successfully demodulated in the MW band (5.8 GHz) and THz band (150 GHz), respectively, thus validating the performances of the receiver. To the best of the authors' knowledge, this is the first interferometric receiver that operates in both MW and THz frequencies, simultaneously.