Abstract: A telemetric process for measuring short distances comprises emitting an electromagnetic signal modulated by a pseudo-random sequence having a number (n) of bits delivered at a clock frequency (fH), correlating the echo detected with the modulated signal time-delayed by known means, and varying the clock frequency, as a function of the correlation measurement, within an operational field divided into a plurality of operating ranges, the number of bits inthe pseudo-random sequence being modified accoridng to the operating range of the clock frequency. The process is particlualry useful for proximity measurement close to a reflecting surface.

Abstract: A continuous emission radar device for determining, at short range, the relative positions of a missile and a vehicle to which the device is fitted, includes a transmitting circuit connected to a transmitting antenna for emitting a continuous signal modulated by a pseudo-random binary sequence delivered at a clock frequency fH, and three receiving circuits connected respectively to three receiving antennae which receive echos of the emitted signal from the missile, a first receiving circuit generating the clock frequency and slaving it to the missile vehicle distance, and the other two receiving circuits determining the phase shift between the echo received by the first antenna and each of the echos received by the other two antennae, these three parameters being transmitted to a device for calculating the position of the missile in relation to the vehicle.