Multi functional D band I/Q modulator/demodulator MMICs in SiGe BiCMOS technology
Abstract This paper presents the design and characterization of a D band (110 170 GHz) monolithic microwave integrated direct carrier quadrature modulator and demodulator circuits with on chip quadrature local oscillator (LO) phase shifter and radio frequency (RF) balun fabricated in a 130 nm SiGe BiCMOS process with ft/fmax of 250 GHz/400 GHz. These circuits are suitable for low power ultra high speed wireless communication and can be used in both homodyne and heterodyne architectures. In single sideband operation, the modulator demonstrates a maximum conversion gain of 9.8 dB with 3 dB RF bandwidth of 33 GHz (from 119 GHz to 152 GHz) The measured image rejection ratio (IRR) and LO suppression are 19 dB and 31 dB, respectively. The output P1dB is 4 dBm at 140 GHz RF and 1 GHz intermediate frequency (IF) and the chip consumes 53 mW dc power. The demodulator, characterized as an image reject mixer, exhibits 10 dB conversion gain with 23 dB IRR. The measured 3 dB RF bandwidth is 36 GHz and the IF bandwidth is 18 GHz. The active area of both the chips is 620 um x 480 um including the RF and LO baluns. A 12 Gbit/s QPSK data transmission using 131 GHz carrier signal is demonstrated on modulator with measured modulator to receiver error vector magnitude of 21%
International Journal of Microwave and Wireless Technologies