SIGNAL PROCESSING APPARATUS

• US 3,720,952 A
• Filed: 12/29/1964
• Issued: 03/13/1973
• Est. Priority Date: 12/29/1964
• Status: Expired due to Term

• Current Assignee: Leo Lawsine
• Original Assignee: Leo Lawsine
• Inventors: Lawsine, Leo
• Primary Examiner(s): Feinberg, Samuel
• Assistant Examiner(s): Montone, G. E.
• Application Number:
  US04/421,826
• Time in Patent Office: 2,996 Days
• Field of Search: 343/18,18E,6.5,6.8
• US Class Current: 342/15
• CPC Class Codes: G01S 7/38 Jamming means, e.g. producing false echoes

Abstract

1. Apparatus for processing radar signals and the like, comprising WIDEBAND SIGNAL RECEIVING AND TRANSMITTING ANTENNA MEANS; CIRCULATOR MEANS HAVING A FIRST TERMINAL CONNECTED WITH SAID ANTENNA MEANS, SAID CIRCULATOR MEANS INCLUDING ALSO SECOND AND THIRD TERMINALS; A FIRST TUNED MICROWAVE MIXER SET INCLUDING A FIRST DIRECTIONAL FILTER, A PLURALITY OF FIRST DIRECTIONAL FILTER MIXER UNITS EACH TUNED TO A DIFFERENT DISCRETE FREQUENCY BAND, AND FIRST MANIFOLD MEANS CONNECTING SAID FIRST MIXER UNITS WITH SAID FIRST DIRECTIONAL FILTER; A SECOND TUNED MICROWAVE MIXER SET INCLUDING A SECOND DIRECTIONAL FILTER, A PLURALITY OF SECOND DIRECTIONAL FILTER MIXER UNITS CORRESPONDING IN NUMBER WITH SAID FIRST MIXER UNITS AND BEING TUNED TO THE CORRESPONDING FREQUENCY BANDS THEREOF, RESPECTIVELY, AND SECOND MANIFOLD MEANS CONNECTING SAID SECOND MIXER UNITS WITH SAID SECOND DIRECTIONAL FILTER; FIRST COMMON CONDUCTOR MEANS CONNECTING THE MIXTURE UNITS OF THE FIRST SET WITH THE SECOND TERMINAL OF SAID CIRCULATOR MEANS, SAID FIRST CONDUCTOR MEANS CONTAINING SERIES-CONNECTED SERIESCONNECTED SWITCH; SECOND COMMON CONDUCTOR MEANS CONNECTING THE MIXTURE UNITS OF THE SECOND SET WITH THE THIRD TERMINAL OF SAID CIRCULATOR MEANS; LOCAL OSCILLATOR SIGNAL GENERATOR MEANS; FIRST GATE MEANS CONNECTING SAID SIGNAL GENERATOR MEANS WITH ALL OF THE MIXER UNITS OF SAID FIRST SET; A PLURALITY OF SECOND GATE MEANS CONNECTING SAID SIGNAL GENERATOR MEANS WITH THE MIXTURE UNITS OF SAID SECOND SET, RESPECTIVELY; AND SIGNAL PROCESSING MEANS HAVING INPUT AND OUTPUT TERMINALS CONNECTED WITH THE DIRECTIONAL FILTERS OF SAID FIRST AND SECOND SETS, RESPECTIVELY, FOR CONTROLLING THE OPERATION OF SAID SWITCH AND OF SAID FIRST AND SECOND GATING MEANS AS A FUNCTION OF THE INHERENT CHARACTERISTICS OF SIGNALS RECEIVED BY SAID ANTENNA MEANS AND FOR RETURNING TO THE DIRECTIONAL FILTER MEANS OF SAID SECOND SET A MODIFIED FACSIMILE SIGNAL.

Claims

1. Apparatus for processing radar signals and the like, comprising wideband signal receiving and transmitting antenna means;

circulator means having a first terminal connected with said antenna means, said circulator means including also second and third terminals;

a first tuned microwave mixer set including a first direCtional filter, a plurality of first directional filter mixer units each tuned to a different discrete frequency band, and first manifold means connecting said first mixer units with said first directional filter;

a second tuned microwave mixer set including a second directional filter, a plurality of second directional filter mixer units corresponding in number with said first mixer units and being tuned to the corresponding frequency bands thereof, respectively, and second manifold means connecting said second mixer units with said second directional filter;

first common conductor means connecting the mixer units of the first set with the second terminal of said circulator means, said first conductor means containing a series-connected switch;

second common conductor means connecting the mixer units of the second set with the third terminal of said circulator means;

local oscillator signal generator means;

first gate means connecting said signal generator means with all of the mixer units of said first set;

a plurality of second gate means connecting said signal generator means with the mixer units of said second set, respectively; and

signal processing means having input and output terminals connected with the directional filters of said first and second sets, respectively, for controlling the operation of said switch and of said first and second gating means as a function of the inherent characteristics of signals received by said antenna means and for returning to the directional filter means of said second set a modified facsimile signal.

2. Apparatus for processing and repeating radar signals and the like, comprising wideband signal receiving and transmitting antenna means;

first and second circulator means each having a first terminal connected with said antenna means, and second and third terminals;

first, second, third and fourth microwave mixer sets each including a directional filter, a plurality of directional filter mixer units each tuned to a different discrete frequency band, and manifold means connecting said filter mixer units with said directional filter, the mixer units of said first and second sets being of the same number and having corresponding frequency bands, respectively, the mixer units of said third and fourth sets being of the same number and having corresponding frequency bands, respectively;

first common conductor means including a first switch connecting the mixer units of the first set with the second terminal of said first circulator means;

second common conductor means connecting the mixer units of the second set with the third terminal of said first circulator means;

third conductor means including a second switch connecting the mixer units of said third mixer set with the second terminal of the second circulator means;

fourth conductor means connecting the mixer units of said fourth mixer set with the third terminal of the second circulator means;

signal processing and modifying means having input and output terminals;

first diplexer means connecting the directional filters of said first and third mixer sets with the input terminal of said signal processing and modifying means;

second diplexer means connecting the output terminal of said signal processing and modifying means with the directional filters of said second and fourth mixer sets;

local oscillator signal generator means;

first gate means connecting said signal generator means with each of the mixer units of said first and third mixer sets; and

a plurality of second gate means connecting said signal generator means with the mixer units of said second and fourth mixer sets, respectively;

said signal processing and modifying means being operable in accordance with the inherent characteristic of the signal received by said antenna means to control the operation of said first and second gate means and said first and second switches.

3. An electronic countermeasure syStem for processing the aircraft-seeking signals generated by a hostile radar installation and for repeating to said radar installation false target echo signals, comprising wideband antenna means operable alternately to receive a first radar signal and to transmit a processed second radar signal;

microwave front end means connected with said antenna means and including first tuned mixer means for placing said first signal within a given first frequency band;

second mixing means for modifying the output signal of said front end means to produce a signal characteristic of, and having a lower frequency than, said first radar signal;

delay means for delaying said low frequency signal, said delay means including a variable delay device;

doppler correcting means controlling the operation of said variable delay device to effect a doppler frequency shift of said low frequency signal corresponding to a desired repeated echo range rate;

means including third mixer means for placing the delayed and doppler corrected signal in said first frequency band;

means including said first tuned mixer means for converting the delayed and doppler corrected signal in said first frequency band to the original frequency of said first radar signal and thereby produce said second radar signal;

means including said antenna for transmitting said second radar signal toward said hostile radar installation; and

computer means responsive to the low frequency signal produced by said second mixing means for controlling the operation of said first mixing means.