Continuous emission radar device for determining, at short range, the relative positions of a missile and a vehicle to which the device is fitted

• US 5,140,330 A
• Filed: 09/12/1991
• Issued: 08/18/1992
• Est. Priority Date: 09/18/1990
• Status: Expired due to Fees

• Current Assignee: Societe Nationale D'Etude Et De Construction De Moteurs D'Aviation
• Original Assignee: Societe Nationale D'Etude Et De Construction De Moteurs D'Aviation
• Inventors: Le Garrec, Guy, Sebilet, Bruno R.
• Primary Examiner(s): Hellner, Mark
• Application Number:
  US07/757,929
• Time in Patent Office: 341 Days
• Field of Search: 342/146, 342/133, 342/118
• US Class Current: 342/146
• CPC Class Codes: G01S 13/325 using transmission of coded signals, e.g. P.S.K. signals
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence

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.

Claims

1. A continuous emission radar device for determining, at short range, relative positions of a missile and a vehicle to which the device is fitted, said device comprising:

a transmitting antenna;

a transmitter circuit connected to said transmitting antenna for emitting a continuous signal modulated by a pseudo-random binary sequence delivered at a clock frequency fH;

a first receiving antenna for receiving a first echo of said emitted signal;

a first receiving circuit connected to said first receiving antenna and comprising;

first correlating means for generating a first correlation signal representing a correlation between said first echo and the emitted signal delayed by a time delay corresponding to a journey of said emitted signal between said transmitting antenna and said missile and between said missile and said first receiving antenna, and

a frequency-controllable generator receiving said first correlation signal and generating a signal at said clock frequency fH, this frequency fH being representative of a distance between said missile and said vehicle;

a second receiving antenna for receiving a second echo of said emitted signal;

a second receiving circuit connected to said second receiving antenna and arranged to determine a phase shift between said first and second echos;

a third receiving antenna for receiving a third echo of said emitted signal;

a third receiving circuit connected to said third receiving antenna and arranged to determine a phase shift between said first and third echos; and

means for calculating a position of the missile relative to the vehicle from said clock frequency fH and the phase shifts determined by said second and third receiving circuits.

2. A device in accordance with claim 1, wherein said second receiving circuit comprises:

second correlating means for generating a second correlation signal representing a correlation between said second echo and said time-delayed emitted signal; and

means for measuring a phase shift between said first correlation signal and said second correlation signal;

and said third receiving circuit comprises;

third correlating means for generating a third correlation signal representing a correlation between said third echo and said time-delayed emitted signal; and

means for measuring a phase shift between said first correlation signal and said third correlation signal.

3. A device in accordance with claim 1, wherein said transmitting antenna is aligned with said first and second receiving antennae along a longitudinal axis of said vehicle, and said first and third receiving antennae are aligned along an axis not parallel to said longitudinal axis of said vehicle.

4. A device in accordance with claim 1, wherein said first and second receiving antennae, and also said first and third receiving antennae, are spaced apart from each other by a distance no more than a half wavelength of said continuous signal.

5. A device in accordance with claim 3, comprising said third receiving antenna being aligned along an axis perpendicular to said longitudinal axis.