Abstract: A swept-frequency radar system transmits pulses consisting of swept-frequency subpulses of nonuniform duration separated by short nontransmitting periods during which an array antenna is resteered. The pulses reflected from a target are processed by a method including estimating the target ranges, producing a reference signal at the time at which the pulse reflected from the target is expected to return. The reflected pulse is phase detected by means of the reference pulse to produce phase detected signals which include information relating to the error between the actual range and the estimated range. The phase detected signals are Fourier transformed to produce range error information. The nonuniform subpulse durations reduce the magnitude of range sidelobes.

Abstract: An envelope detector with an extended linear dynamic range. A first amplitude modulated carrier signal, which can be of an intermediate frequency, is supplied to a first input terminal of a mixer, preferably balanced. The said first signal is also amplified and limited to produce a second signal which is phase synchronized with the carrier signal of said first signal, and which is supplied to the local oscillator input terminal of the mixer. The mixer responds to said first and second signals to produce a substantially dc (baseband) output signal whose waveform is similar to the envelope of said first signal.