Four-quadrant detector signal amplifying circuit for laser radar

Abstract

The invention discloses a four-quadrant detector signal amplifying circuit for a laser radar. The circuit comprises a four-quadrant detector, wherein current signals output after the four-quadrant ofthe four-quadrant detector performs photoelectric conversion are respectively sent to a first-stage amplifying circuit, the first-stage amplifying circuit converts the current signals into voltage signals and performs signal amplification, and the output signal of the first-stage amplifying circuit is sent to a second-stage amplifying circuit for amplification. The four-quadrant detector signal amplifying circuit for a laser radar sets the feedback resistance value of the first-stage amplifying circuit to a specific range to effectively improve the response bandwidth, so that the output voltage of the first-stage amplifying circuit can be used for subsequent processing when the output of the two-stage amplifying circuit is detected to be saturated in close range, thereby ensuring the detection accuracy, and improving the detection dynamic range. And the amplification factor of the second-stage amplifying circuit is taken to be not less than 500, and the total amplification factor of the entire four-quadrant detector signal amplifying circuit is FORMULA, thereby increasing the gain, increasing the radar detectable distance, and improving the detection precision.

Description

technical field [0001] The invention relates to the field of laser radar, in particular to a four-quadrant detector signal amplification circuit for laser radar. Background technique [0002] Four-quadrant detector (QD) is widely used in laser alignment, laser centering, laser guidance, laser guidance, laser warning, laser reconnaissance, laser automatic detection, etc. Tracking etc. The four-quadrant detector is integrated with four photocells with almost identical performance in the form of four-quadrant distribution, and uses the magnitude of the light signals output by the four quadrants to calculate and locate the light spot according to a certain algorithm. Four-quadrant detectors are used in laser detection applications such as lidar. The laser echo signal is often weak, the laser repetition rate is high, and the laser pulse width is narrow. Lidar often requires a large detection dynamic range. Therefore, the four-quadrant detector signal amplification circuit requir...

AI Technical Summary

Problems solved by technology

However, in the existing technology, the use of a one-stage amplification structure cannot meet the requirements. Generally, multi-stage amplification and gain control methods are used, but the technology is relatively complicated.

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