The constant fraction discriminator in pulsed time-of-flight laser rangefinding

Constant Fraction Discriminator (CFD) is one of the theoretic method which can locate the timing point at same fraction of the echo pulse in pulsed Time-of-Flight (TOF) laser rangefinding. In this paper, the theory of CFD method was analyzed in reality condition. The design, simulation and the PCB performance of the CFD circuit were shown. At last, the over amplify method was introduced. By which, the influence of DC bias error could be reduced. The experimental results show that our timing discriminator can set the timing point does not depend on the amplitude of echo pulse.