GB591130A - Improvements in or relating to wireless systems - Google Patents

Abstract

591,130. Radiolocation. WATT, R. A. W. Sept. 15, 1938, No. 25133. [Class 40 (v)] A cathode-ray tube is used for the measurement of the time interval between the emission of a radio signal at the locating-station and the receipt of a re-radiated signal .from the target or object to be located. The target carries a receiver responsive to signals, e;g. pulses, from the locating-station, and a transmitter for emitting signals on the same, a related, or an unrelated radio frequency and stimulated by the receipt of a signal. The signal from the locating station may be a single-pulse or a sequence of pulses of regular or irregular recurrence frequency. Means may be provided for restricting the solid angle utilised by the radiation emitted by the sender or accepted by the receiver at the locating-station ; and the direction of the target may be ascertained by measurement of angles of azimuth and altitude, e.g. as described in. Specification 252,263, [Class 40 (v)]. The signals from either station may have a special form for restricted response or for identification. The CR tube at the locating station indicates on a calibrated time scale both the emitter pulse or signal and the secondary pulse or signal from the target. The time base may be released by the emitted pulse and may be synchronized to a series of recurrent pulses. The receiver of the re-radiated signals is preferably at a short distance from the sender of the locating- station.