GB593017A - Improvements in or relating to wireless systems - Google Patents

Improvements in or relating to wireless systems

Info

Publication number
GB593017A
GB593017A GB2577035A GB2577035A GB593017A GB 593017 A GB593017 A GB 593017A GB 2577035 A GB2577035 A GB 2577035A GB 2577035 A GB2577035 A GB 2577035A GB 593017 A GB593017 A GB 593017A
Authority
GB
Grant status
Application
Patent type
Prior art keywords
object
pulse
waves
arrays
angles
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB2577035A
Original Assignee
Robert Alexander Watson Watt
Filing date
Publication date

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems

Abstract

593,017. Radiolocation. WATT, R. A. W. Sept. 17, 1935, No. 25770. [Class 40 (v)] Aircraft, marine craft, or other objects are located by radiating intermittent carrier wave pulses and receiving in an indicating receiver the pulses reflected or re-radiated from the object. The primary radiation may be broadcast through large solid angles, and the receiving aerials may be designed to accept waves from corresponding angles, to avoid the necessity for searching for the object. The solid angles may be restricted to minimize interference from unwanted signals and atmospherics. The receiver and transmitter may either be adjacent or separated in space; and observation is taken of the time delay between a pulse received directly from the transmitter and a pulse received after reflection. If the pulse duration is longer than this time delay, the two received pulses are superposed, and the delay is measured from the beginning of the direct pulse to the change in amplitude caused by the superposition of the reflected pulse. The azimuth and elevation angles are determined by direction finding on the reflected waves. The vertical and horizontal dimensions of the object may be approximately determined by using waves of corresponding polarization, and by variation of the emitted wavelength until maximum response is obtained. If the object is a friendly craft, or a meteorological balloon, it may be provided with resonant radiators to increase the re-radiated energy, which may be keyed or modulated for identification or other purposes. Fig. 6 shows a suitable transmitter aerial array for giving radiation of low elevation and with a cardioid polar diagram in the horizontal plane. It comprises a stack of horizontal half-wave dipoles A ... F spaced half a wavelength apart in the vertical direction, and backed by a corresponding stack A<1> ... F<1> a quarter-wavelength behind. The receiving array may be similar, and it may comprise also a second array at right angles to the first, the two arrays being used as crossed pick-up systems of an aural or visual direction finder. Two receiving systems of this kind may be set up at a suitable distance apart as shown in plan in Fig. 8, and the angle of elevation of incoming waves determined by known means by comparison of the electromotive forces induced in the arrays. The stacks in the forward and rear arrays may be coupled to radiogoniometers, the search coils of which are mechanically linked, and are coupled together through phase-changing devices to a crossedcoil transformer serving as a phase-comparator. The single receiver thus fed from the two arrays is arranged to produce vertical deflection on a C.R. tube in which horizontal deflection is provided by a time base operating at pulse frequency, thus giving a range indication. By rotating the search coils, the echo pulse may be made to disappear at an angular setting which gives the azimuth of the reflecting object. These search coils are then re-set close to the angle of maximum response, and the third search coil rotated until the echo pulse disappears, its reading then being a measure of the angular elevation of the object. By employing two range-finding systems, the position of an object may be fixed by triangulation. If the range of an object is already known, the system may be used to measure the velocity of radio waves. Specification 252,263, [Class 40 (v)], is referred to.
GB2577035A 1935-09-17 Improvements in or relating to wireless systems Expired GB593017A (en)

Publications (1)

Publication Number Publication Date
GB593017A true true GB593017A (en) 1937-05-31

Family

ID=1739501

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2577035A Expired GB593017A (en) 1935-09-17 Improvements in or relating to wireless systems

Country Status (1)

Country Link
GB (1) GB593017A (en)

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