A 219-266 GHz LO-tunable direct-conversion IQ receiver module in a SiGe HBT technology

This paper presents a fully-integrated direct-conversion fundamentally-operated mixer-first quadrature receiver module with a tunable LO in the 219-266 GHz band. It has been implemented in a 0.13-mu m SiGe heterojunction bipolar transistor technology. It includes an on-chip LO path driven externally from the printed circuit board (PCB) connector level at 13.6-16.7 GHz. A hybrid coupler generates the quadrature LO signal, which drives a pair of double-balanced fundamentally-operated down-conversion mixers, whose RF ports are connected to a wideband lens-integrated on-chip ring antenna. The chip-on-lens assembly is placed in the recess of a high-speed PCB and wire-bonded. To compensate the inductive behavior of the wire-bond interconnection between the chip and the PCB at the high-speed IF outputs, an on-board 8-section step-impedance low-pass filter has been implemented. The module shows a 47 GHz 3-dB radio frequency/local oscillator operation bandwidth (BW), a peak conversion gain of 7.8 dB, a single-side-band noise figure of 11.3 dB, and a 3-dB IF BW of 13 GHz. The in-phase and quadrature amplitude imbalance stays below 1.58 dB for the 210-280 GHz band. The down-conversion and the baseband stages consume together 75.5 mW, while the LO path 378 mW. The maximum data-rate achieved with this receiver in combination with the transmitter presented in [1-3] is 60 Gbps for quadrature phase shift keying modulation.