Theoretical and Experimental Investigation of HMSIW-Based High-Speed Data Transmission System Using QPSK Scheme

Half-mode substrate integrated waveguide (HMSIW) is a high-pass transmission line, which can be easily integrated into planar circuits. Compared with SIW, HMSIW features wider relative bandwidth and smaller size. The quadrature phase-shift keying (QPSK) scheme can double the signal transmission rate compared with a simple mixing scheme. In this paper, an HMSIW with 8-24-GHz frequency band is designed and fabricated, and then a high-speed data transmission system using the QPSK scheme is implemented based on the HMSIW. The mathematic modeling of the system is provided to analyze time-domain response and crosstalk of the system, and then accurate control of the amplitude and the phase is realized by the introduction of amplifier and phase shifter. Hence, the amplitude attenuation caused by the loss of the components and phase differences has been compensated, and the crosstalk caused by the phase differences has been eliminated. The above-mentioned modeling is validated by experimental results. Comparisons are also made between the system with and without the amplifier/phase shifter. It is shown that the system can transmit the signal with 15-Gb/s data rate by one physical channel. A high data rate and low bit error rate are obtained in the proposed system.