Combined cw and pulse tracking systems

Claim 2

A radar tracking system having a transmitter for emitting signals and a receiver for intercepting emitted signals and manipulating such intercepted signals to track frequency and range, with such signals being subject to doppler shifts, the improvement including in combination, means in the transmitter for supplying phase coherent continuous-wave and RF pulse signals which are emitted one with the other as a composite signal, CW means in the receiver responsive to intercepted continuouswave signals to adjust receiver operation to the frequency of the intercepted wave and range means in the receiver responsive to such adjustment to initiate a tracking operation for tracking range in response to intercepted pulse signals.

Claim 3

The system as set forth in claim 1 wherein said range means is responsive to intercepted pulse signals for adjusting receiver operation to detect range simultaneously with the CW means adjusting receiver operation to the frequency of the intercepted wave and further operative upon detection of range to initiate a range tracking operation.

Claim 4

The system set forth in claim 1 wherein the receiver includes a pair of range tracking channels both of which simultaneously receive said intercepted pulse signals, energy comparison means connected to said range channels and responsive to detecting a first pulse energy in a first one of said channels to supply a first indication that the receiver has detected range and responsive to such first indication for initiating a range tracking operation and responsive to detecting a second energy in a second one of said channels to supply a second indication and responsive to said second indication to initiate frequency tracking by said CW means to thereby readjust the receiver operation to the frequency of the intercepted wave.

Claim 5

The system of claim 3 wherein said CW means includes a velocity tracking system for adjusting a receiver tuned frequency toward the intercepted CW signal frequency, a third range channel in said range means for receiving said intercepted CW and pulse signals and connected to said velocity tracking system for indicating the relationship of the intercepted CW signal frequency to a frequency of a signal generated in said velociTy tracking system and accepting said CW signals while the receiver is being adjusted to said intercepted CW signal frequency, and control means in the receiver connected to said comparison means and operative to selectively initiate a range tracking operation in response to said first indication and connected to said third channel for selectively activating said channel during interception of said pulse signals for blocking out certain CW signals intermediate said pulse signals and being responsive to said second indication to actuate said third channel to continuously receive signal.

Claim 6

The system as in claim 4 wherein said comparison means includes frequency translating means for frequency translating signals received from said second channel, summing means for summing the signals from said first channel with said frequency translated signals, limiter means connected to the summer means for receiving and limiting said summed signals, frequency responsive energy detector means responsive to said limited signals to indicate which of said summed and limited signals has a greater energy, said comparison means supplying said first indication when said first channel has greater energy and supplying said second indication when said second channel has greater energy.

Claim 7

The system of claim 5 wherein said energy detector means comprises, a pair of filter means one of which is tuned to said frequency translated signal and both being connected to the limiter for receiving the limited summed signal, amplitude detector means connected to said filter means and supplying opposite polarity signals when a signal is passed by the respective filters, summer means connected to the detector means for summing the amplitude detector outputs to selectively supply said first and second indications of said summed and limited signal energy.

Claim 8

The system of claim 1 wherein said transmitter means comprises, a source of CW signals, a directional coupler receiving said CW signals and supplying said CW signals as first and second output CW signals, a first channel for passing said first output CW signals, a second channel including pulse modulating means for forming pulsed RF CW signals from said second output CW signals, and energy division means connected to said channels for adjusting the amplitude of said pulsed RF signals with respect to the amplitude of CW signals intermediate successive pulse signals, and means for transmitting said signals.

Claim 9

The system of claim 7 wherein said second channel comprises a diode switch and a modulator in series connection, a modulating signal source connected to both said switch and said modulator for simultaneously selectively actuating same to form pulsed RF signals.

Claim 10

The system of claim 1 wherein said transmitter comprises a transmitting portion and a source of CW signals, a crossfield amplifier receiving said CW signals for passing them to said transmitting portion of the transmitter, and a modulating signal source connected to said amplifier for selectively actuating same to rapidly alter the amplitude of CW signals to form pulse components in signals supplied to the transmitting portion.

Claim 11

A transmitter for a radar tracking system including in combination, a source of CW signals, a directional coupler receiving said CW signals and supplying said CW signals as first and second CW signals, a first channel passing said first CW signals, a second channel including pulse modulating means for selectively forming pulsed RF signals from said received CW signals, means connected to said first and second channels for controlling the relative amplitudes of the said pulsed RF signals and CW signals occurring intermediate successive pulsed RF signals, and means connected to said last mentioned means for transmitting said signals.

Claim 12

A transmitter for a radar tracking system including in combination, a source of CW signals, a directional coupler receiving said CW signals and supplying said CW signals as first and second CW signals, a first channel passing said first CW signals, a second channel including pulse modulating means for selectively forming pulsed RF signals from said received CW signals, means connected to said first and second channels for controlling the relative amplitudes of the said pulsed RF signals and CW signals occurring intermediate successive pulsed RF signals, and means connected to said last mentioned means for transmitting said signals.

Claim 13

The transmitter of claim 10 wherein said second channel Includes an interconnected electroresponsive switch and an RF pulse amplifier with said switch receiving and selectively forming RF pulses from said CW signals and said amplifier receiving said RF pulses, a pulse source connected to both said switch and said amplifier for simultaneously selectively supplying pulses thereto.

Claim 14

A transmitter for a ranging system and having a transmission portion, the improvement including in combination, a source of CW signals, a crossfield amplifier receiving said CW signals for passing them to a radiating portion of the transmitter, and a pulse source connected to said amplifier for selectively altering the amplitude of CW signals supplied to the transmission portion.

Claim 15

A transmitter for a ranging system and having a transmission portion, the improvement including in combination, a source of CW signals, a crossfield amplifier receiving said CW signals for passing them to a radiating portion of the transmitter, and a pulse source connected to said amplifier for selectively altering the amplitude of CW signals supplied to the transmission portion.

Claim 16

A receiver for a radar tracking system having means for intercepting a ranging signal and a portion to frequency track such intercepted signal, and means for deriving a range indicating signal from such intercepted signal, the signal having both CW and RF pulse signal components, the receiver improvement including in combination, early gate means including a selectively actuable detector, energy control means and amplitude detectors, and receiving said range signals, said energy control means supplying an output signal to the frequency tracking portion for adjusting the tuning of the receiver to a frequency having a predetermined relationship to an intercepted signal CW component frequency, a pair of additional gate means consisting of a late and an extra early gate means each including selectively actuable detectors, energy control means and amplitude detectors, tracking mode control means connected to said gate means selectively actuable detectors for selectively sequentially actuating said extra early and late gate detectors according to range being detected and always actuating said extra early gate means first, and said tracking mode control means including energy comparison means for detecting and comparing energies in said gate means and being responsive to detecting an energy in one of said additional gate means greater than an energy in another additional gate means to selectively actuate said early gate means in accordance with signals received from all said gate means amplitude detectors, and actuating said early gate means detector only after actuating said extra early gate means.

Claim 17

A receiver for a radar tracking system having means for intercepting a ranging signal and a portion to frequency track such intercepted signal, and means for deriving a range indicating signal from such intercepted signal, the signal having both CW and RF pulse signal components, the receiver improvement including in combination, early gate means including a selectively actuable detector, energy control means and amplitude detectors, and receiving said range signals, said energy control means supplying an output signal to the frequency tracking portion for adjusting the tuning of the receiver to a frequency having a predetermined relationship to an intercepted signal CW component frequency, a pair of additional gate means consisting of a late and an extra early gate means each including selectively actuable detectors, energy control means and amplitude detectors, tracking mode control means connected to said gate means selectively actuable detectors for selectively sequentially actuating said extra early and late gate detectors according to range being detected and always actuating said extra early gate means first, and said tracking mode control means including energy comparison means for detecting and comparing energies in said gate means and being responsive to detecting an energy in one of said additional gate means greater than an energy in another additional gate means to selectively actuate said early gate means in accordance with signals received from all said gate means amplitude detectors, and actuating said early gate means detector only after actuating said extra early gate means.

Claim 18

The receiver set forth in claim 13 wherein said energy comparison means includes frequency translating means connected to a first one of said additional gate means, signal summing means connected to a second one of said additional gate means to said frequency translating means for receiving signals therefrom and supplying a summation of such signals, a limiter receiving said summation signal and supplying an energy limited summation signal, frequency responsive amplitude detector means responsive to said limited signal and supplying indicia of which one of said pair of gate means has a greater energy signal and selectively actuating said early gate means detector in accordance with said indicia.

Claim 19

The receiver set forth in claim 14 wherein each of said energy control means consists of a filter and a limiter, the filter receiving signals from the respective gate means detectors and supplying band passed signals to the limiter.

Claim 20

The receiver set forth in claim 15 wherein said energy comparison means is connected to both said additional gate means filter means for receiving filtered non-limited signals therefrom.

Claim 21

The receiver set forth in claim 16 wherein said one additional gate means is the late gate means whereby the receiver is operative to track on wavefronts of said intercepted RF pulse signals.

Claim 22

The receiver set forth in claim 17 wherein said comparison means amplitude detector means has first and second filters for respectively passing a frequency translated limited signal and a limited second channel signal derived from said limited summation signal, a pair of amplitude detectors respectively connected to said first and second filters for supplying amplitude detected signals, amplitude summation means responsive to said amplitude detected signals for supplying said indicia.

Claim 23

The receiver set forth in claim 18 wherein said amplitudes summation means includes two-state switching means responsive to said amplitude detected signals indicating a first relative energy in said late gate means to supply a first digital signal for causing a tracking operation and to said detected signals indicating a greater energy in said extra early gate to inhibit said first digital signal, and said control means continuously actuating said early gate detector in response to said first digital signal being inhibited.

Claim 24

The receiver set forth in claim 13 further including bias switching means responsive to detection of greater energy in said late gate to supply a digital bias signal, means combining signals from said gate means amplitude detectors forming a combined range tracking signal, gate generating means in said tracking mode control means and responsive to said bias signal to actuate said early gate means detector in accordance with said combined signal and operative when not receiving said bias signal to actuate said late and extra early gate detectors such that the frequency of actuations is different than a repetitive frequency of the pulse components of the intercepted signal and simultaneously continuously actuate said early gate detector.

Claim 25

The receiver set forth in claim 13 wherein said tracking mode control means includes signal summing means connected to all said amplitude detectors for receiving amplitude detected signals therefrom and supplying a sum signal derived from said amplitude detected signals, said signal summing means weighting said sum signal to that of said early gate means amplitude detector supplied amplitude detected signal for causing said gate generating means to actuate said selectively actuable detectors in each said gate means such that said early gate means tends to receive more signal energy than said extra early gate means but less signal energy than said late gate means.

Claim 26

A radar tracking system having a transmitter for emitting signals and a receiver for intercepting emitted signals with circuits for manipulating such intercepted signals to track frequency and range, with such signals being subject to doppler shifts, the improvement, including in combination, means in the transmitter for generating a continuous wave signal having repetitive amplitude perturbations each with a leading and trailing portion and such continuous wave signal with repetitive amplitude perturbations being emitted by the transmitter as a composite signal, CW means in the receiver responsive to intercepted continuous wave signals to adjust receiver circuits to the frequency of the intercepted wave and range means in the receiver having selectively actuated detector means and including tracking mode control means operative to detect adjustment of certain receiver circuits and responsive to said certain receiver circuits being adjusted to the frequency of the intercepted wave to actuate said selectively actuated detector means in approximate time coincidence with one of said portions for detecting said amplitude perturbations for initiating a range tracking operation in said range means, said range means being responsive during said range tracking operation to said one portion of said amplitude perturbation to adjust said tracking mode control such that actuation of said selectively actuated detector means is maintained in a predetermined time relationship to repetitive occurrence of said one portion whereby said receiver is continuously adjusted for continuously detecting said amplitude perturbations.

Claim 27

A radar tracking system having a transmitter for emitting signals and a receiver for intercepting emitted signals with circuits for manipulating such intercepted signals to track frequency and range, with such signals being subject to doppler shifts, the improvement, including in combination, means in the transmitter for generating a continuous wave signal having repetitive amplitude perturbations each with a leading and trailing portion and such continuous wave signal with repetitive amplitude perturbations being emitted by the transmitter as a composite signal, CW means in the receiver responsive to intercepted continuous wave signals to adjust receiver circuits to the frequency of the intercepted wave and range means in the receiver having selectively actuated detector means and including tracking mode control means operative to detect adjustment of certain receiver circuits and responsive to said certain receiver circuits being adjusted to the frequency of the intercepted wave to actuate said selectively actuated detector means in approximate time coincidence with one of said portions for detecting said amplitude perturbations for initiating a range tracking operation in said range means, said range means being responsive during said range tracking operation to said one portion of said amplitude perturbation to adjust said tracking mode control such that actuation of said selectively actuated detector means is maintained in a predetermined time relationship to repetitive occurrence of said one portion whereby said receiver is continuously adjusted for continuously detecting said amplitude perturbations.