A 80-95 GHz direct quadrature modulator in SiGe technology
Paper in proceedings, 2014

A direct carrier IQ modulator operating in the 80-95 GHz frequency range is presented. The circuit is designed and fabricated in 0.18μm SiGe technology with 170/250 GHz fT/fmax. The modulator is based on double-balanced gilbert mixer cells with on-chip quadrature LO phase shifter and consumes 23mW DC power. In single-sideband operation, the chip exhibits up to 3 dB conversion gain below 85 GHz and -1± 0.5 dB up to 95 GHz. The image rejection ratio and LO-RF isolation are as high as 25 dB and 43 dB respectively. The modulator can operate with 10 GHz of modulation bandwidth and delivers -7 dBm power in saturation. For demonstration, the circuit is tested and shown to be capable of transmitting 4Gbps BPSK signal with NRZ rectangular pulses. The active chip area is 480μm× 260μm. © 2014 IEEE.

Gilbert cell mixer

Quadrature modulator

SiGe Bipolar Transistor




Morteza Abbasi

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Sona Carpenter

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Herbert Zirath

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

F. Dielacher

Infineon Technologies

SiRF 2014 - 2014 IEEE 14th Topical Meeting on Silicon Monolithic Integrated Circuits in RF Systems


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