Abstract: For use in cancelling a distortion caused by multipath transmission to an original radio frequency pulse of an original pulse shape, a multipath canceller comprises a priliminary circuit for producing a distortionless pulse of the original pulse shape and a distortion cancelling circuit responsive to the distortionless pulse and each distorted pulse having the distortion for producing a distortion cancelled pulse at a correct pulse position which the original pulse would have if received through a direct path alone. The preliminary circuit may comprise a memory for the distortionless pulse.

Abstract: In a distance measuring equipment for measuring the distance between an interrogator and a transponder with high precision by detecting the time from transmission of an interrogation pulse from the interrogator to reception of a reply pulse transmitted from the transponder on the basis of timing positions of said respective pulses; as leading edges of the interrogation pulse and reply pulse, a waveform represented by the formula of: ##EQU1## where E and F represent finite positive values and T represents time, is used, or else as a leading edge of the interrogation pulse, a waveform which can be approximated by the above formula is used, while as a leading edge of the reply pulse, a waveform obtained by passing a waveform approximately expressed by the formula of: ##EQU2## through a low-pass filter having a predetermined cut-off frequency, is used.