Dual-Channel Half-Mode Substrate-Integrated Waveguide Link Utilizing Mode Division Multiplexing

This article presents a dual-mode communication link integrated on PCB that utilizes mode division multiplexing between the fundamental and the first higher-order mode of a half-mode substrate-integrated waveguide (HMSIW). The paper introduces methods for selective excitation of both modes. We also demonstrate real-time channel measurements with a pseudo-random binary sequence (PRBS) and a MATLAB simulation of quadrature amplitude (QAM) modulation schemes. To the best of our knowledge, this is the first demonstration of higher-order mode excitation and the first realization of a concurrent dual-mode link on a HMSIW platform. The measured 10-dB return loss bandwidths of the fundamental mode and higher-order mode are 2.6 GHz (12.2-14.8 GHz) and 3 GHz (12-15 GHz) respectively, corresponding to a concurrent bandwidth of 2.6 GHz with less than 200 ps of group delay variation and more than 20 dB of isolation between the channels. The measurement results agree well with the simulation results.