A 300GHz quadrature down-converter S-MMIC for future terahertz communication

This paper presents a highly broadband quadrature down-converter with a center frequency of 300GHz and a low noise amplifier (LNA) with a bandwidth of 80GHz.The operation frequency between 235GHz and 315GHz enables the usage in future wireless high data rate applications. The submillimeter-wave monolithic integrated circuits(S-MMICs)are realized using a 35 nm metamorphic high electron mobility transistor(mHEMT) technology based on InAlAs/InGaAs. The down-converter integrates a frequency multiplier by four, a buffer amplifier and a passive fundamental I/Q mixer and reaches a conversion gain of -15dB and an RF bandwidth of 60GHz. The low-noise amplifier has an average gain of 26dB over the 3dB bandwidth. A total conversion gain of the receiver of 11dB is therefore reached by combining the down-converter and the LNA.