Monopulse phased array antenna with plural transmit-receive module phase shifters

• US 5,017,927 A
• Filed: 02/20/1990
• Issued: 05/21/1991
• Est. Priority Date: 02/20/1990
• Status: Expired due to Term

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: General Electric Company
• Inventors: Landry, Norman R., Agrawal, Ashok K.
• Primary Examiner(s): Issing, Gregory C.
• Application Number:
  US07/481,415
• Time in Patent Office: 455 Days
• Field of Search: 342/368, 342/371, 342/154, 342/157, 342/158, 342/374, 342/372, 342/373
• US Class Current: 342/371
• CPC Class Codes: G01S 13/4463 using phased arrays
• CPC Class Codes: G01S 7/032 Constructional details for solid-state radar subsystems
• CPC Class Codes: H01Q 21/0025 Modular arrays
• CPC Class Codes: H01Q 25/02 providing sum and difference patterns H01Q25/04 takes precedence
• CPC Class Codes: H01Q 3/22 varying the orientation in accordance with variation of frequency of radiated wave

Abstract

A monopulse antenna array arrangement includes a transmit-receive processor (TR Proc) associated with each antenna element. Each TR Proc has a port associated with the radiating element and at least two further ports, one for a sum beamformer and another for a difference beamformer. Within each TR Proc, a switching arrangement allows transmitter signal to flow through a phase shifter and transmit amp during transmission, and allows received signal to flow through a low-noise amp and the same phase shifter on reception. Each TR Proc includes a coupling arrangement with a second phase shifter and a second output port, adapted to be coupled to a difference beamformer during reception.

Claims

1. A transmit-receive processor adapted for use together with other similar processors in a monopulse radar system, which monopulse radar system includes a plurality of arrayed radiators, and which also includes an azimuth sum channel combiner defining a combined port and plural separated ports, and at least one of an azimuth difference channel combiner and an elevation difference channel combiner, each of which also includes a combined port and plural separated ports, said combined port of said sum channel combiner being adapted for receiving a transmitter signal during a transmit mode of operation, said processor comprising:

transmit amplifying means including an input port and an output port, for amplifying signals to be transmitted by one of said radiators;

receive amplifying means including an input port and an output port, for amplifying signals received by said one of said radiators;

radiator coupling means coupled to said output port of said transmit amplifying means, to said input port of said receive amplifying means, and adapted to be coupled to said one of said radiators, for coupling said signals to be transmitted to said one of said radiators from said transmit amplifying means, and for coupling said signals received by said one of said radiators to said receive amplifying means;

first and second phase shifting means for phase shifting signals passing therethrough;

controllable switch means coupled to said first phase shifting means, and including a first port adapted to be coupled to one of said separated ports of said azimuth sum channel combiner, a second port coupled to said input port of said transmit amplifying means, and a third port, said controllable switch means being for, in a transmit mode, coupling signals to be transmitted by way of said first phase shifting means to said transmit amplifying means, and for, in a receive mode, coupling signals applied to said third port through said first phase shifting means to said first port, whereby transmitted signals and received signals applied to said azimuth sum channel combiner traverse the same phase correction network; and

receive coupling means coupled to said output port of said receive amplifying means, to said third port of said swithc means, to said second phase shifting means, and adapted to be coupled to one of said separated ports of one of said azimuth difference channel combiner and said elevation difference channel combiner, for dividing the amplified received signal produced at said output port of said receive amplifying means into at least first and second portions, and for coupling said first portion of said amplified received signal to said third port of said switch means, said receive coupling means also being adapted for coupling said second portion of said amplified received signal to said one of said distal ports of said one of the azimuth difference channel combiner and said elevation difference channel combiner by way of said second phase shifting means.

2. A processor according to claim 1 wherein said receive coupling means divides said amplified received signal into said first and second portions, and also into a third portion, and wherein said receive coupling means is also adapted for coupling said third portion of said amplified received signal to one of said distal ports of the other one of said azimuth difference channel combiner and said elevation difference channel combiner by way of third phase shifting means.

3. A radar system;

comprising

an array of transmit-receive antennas arranged in rows and columns;

means for beamforming, said means for beamforming including at least one of azimuth and elevation difference beamforming means, said one of said difference beamforming means including plural separated ports, one of said separated ports of said beamforming means being associated with each one of said antennas;

a plurality of transmit-receive processors, each associated with one of said intervals, each of said processors also including transmit amplifying means including an input port and an output port, for amplifying signals to be transmitted by the associated one of the said antennas, said processor also including receive amplifying means including an input port and an output port, for amplifying signals recevied by said associated antenna, each of said processors also including;

antenna coupling means coupled to said output port of said transmit amplifying means, to said input port of said receive amplifying means, and to said associated antenna, for coupling said signals to be transmitted to said associated antenna from said transmit amplifying means, and for coupling said signals received by said associated antenna to said receive amplifying means;

each of said processors also including first and second phase shifting means for phase shifting signals passing therethrough;

each of said processors also including controllable switch means coupled to said first phase shifting means, to an associated one of said separated ports of said sum beamforming means, and to an input port of said transmit amplifying means, said controllable switch means also including a first port, said controllable switch means being for, in a transmit mode, coupling said signals to be transmitted from said associated one of said separated ports of said sum beamforming means, by way of said first phase shifting means, to said transmit amplifying means, and for, in a receive mode, coupling signals which are applied to said first port of said controllable switch means to said associated one of said separated ports of said sum beamforming means by way of said first phase shifting means, whereby transmitted and received signals applied to said sum beamforming means traverse the same phase correction network;

each of said processors further including receive signal coupling means coupled to said output port of said receive amplifying means, to said first port of said switch means, to said second phase shifting means, and to an associated one of said separated ports of said one of said difference produced at said output port of said receive amplifying means into at least first and second portions, and for coupling said first portion of said amplified received signal to said first port of said switch means, and for coupling said second portion of said amplified received signal to said associated separated port of said difference beamforming means by way of said second phase shifting means.

4. A radar system according to claim 3, wherein said sum beamforming means further includes a combined port adapted for receiving transmitter signal during a transmit mode of operation.