A Low-Noise Dual-Photodiode Receiver for Optical Wireless Communication

This paper presents a low-noise dual-photodiode (PD) optical receiver to support gigabit-per-second optical wireless communication (OWC). To improve the photodetection area and sensitivity, a dual-PD fully-differential receiver architecture is employed. In the receiver, a shunt-feedback transimpedance amplifier (SF-TIA) with active feedback is proposed to achieve low noise while maintaining high bandwidth. In addition, an inverter-based limiting amplifier (LA) is employed to increase signal swing. To drive 50 Ω loading, a two-stage output driver (OD) with negative capacitance compensation is designed. The whole receiver is implemented with a 180 nm standard CMOS process. Simulation results indicate that the proposed TIA achieves a transimpedance gain of 86.4 άΒΩ, a −3 dB bandwidth of 1.28 GHz, and an input-referred noise (IRN) of 0.24 μA<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rms</inf>, while the receiver supports data rates beyond 2 Gb/s with an IRN of 0.22 μΑ<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rms</inf>.