Our task was to construct an analog nonlinear amplifier. The amplifier was to be used to measure distance. The output signal should compress the signal such when the input signal changes 1000 times the output signal chages only about ten times. This is because the output signal goes to an A/D-converter, thus A/D-converters do not manage to large voltage interval. To solve this problem we simulated some nonlinear amplifiers and decided to construct an amplifier that realizes a fourth-root transfer function. Very short laserpulses are used to measure the distance. To detect these laserpulses you need wide bandwith and you canít have large timedelay in the circuit if you want the instrument to calculate the true distance. Laserpulses were sent to the target and reflected back to a photodetector. The photodetector generated an input current to the amplifier. The output of the amplifier goes to an A/D-converter. Then the converted signal goes to a DSP or a FPGA that contains algorithms to calculate the distance.