RECEIVER

A range profile digitization circuit for converting a repeating analog input signal into a time series of digital amplitude values, the converter comprising: a signal quantizer arranged to receive the analog input signal and a threshold input and arranged to output a binary value quantized output signal based on a comparison of the input signal with the threshold signal; a plurality of samplers each arranged to sample and hold its input signal upon receipt of a trigger signal; and for each sampler: a plurality of decoders and a demultiplexer arranged to receive an output from the sampler and pass it to a selected one of said decoders based on a selector input. With a plurality of decoders associated with each of the samplers, each sampler can be re-used during the building up of the range profile. To build up the range profile of the signal a decoder is required for each range point in order to convert the thermometer coded input into a digital value. Decoder values may be generated by storing and accumulating the individual bits of the thermometer coded input over multiple pulse transmissions, each bit resulting from a comparison against a threshold value in the swept threshold system. The decoder values provide the amplitude resolution. Counters are one convenient form of decoder.