High Signal-to-Noise Ratio and High-Sensitivity 4-D LiDAR Imaging Receiver

This brief designs and implements a 4-D imaging light detection and ranging (LiDAR) receiver. It employs a reconfigurable transimpedance amplifier (TIA) that alternates between two modes to separately achieve ranging and light intensity quantification functions. A new mode-switching method based on a monostable multivibrator is proposed, allowing the TIA to automatically switch modes during measurement. The reconfigurable TIA and mode-switching method enable the application of charge sampling in 4-D LiDAR imaging receiver, resulting in a higher signal-to-noise ratio (SNR) compared with traditional designs. In addition, the TIA mode used for distance measurement achieves a bandwidth of 140 MHz, a gain of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$99.8~\text {dB}\Omega $ </tex-math></inline-formula>, and an input-referred noise of ~20-nA rms, indicating high detection sensitivity. A prototype implemented in 0.18-um CMOS verifies the feasibility of the proposed receiver, consuming 24.5 mW. Measurement results demonstrate that the prototype can effectively acquire distance and light intensity information of target objects within a range of 5 m.