Abstract: Embodiments include engagement management systems and methods for managing engagement with aerial threats. Such systems include radar modules and detect aerial threats within a threat range of a base location. The systems also track intercept vehicles and control flight paths and detonation capabilities of the intercept vehicles. The systems are capable of communication between multiple engagement management systems and coordinated control of multiple intercept vehicles.

Abstract: A method is provided to improve the impact point for at least one subsequent projectile fired towards a target, launched after an initial projectile, where the subsequent projectiles can alter their course, based on information on the previous projectiles' time of automatic detonation, to improve the ability to detect a target. A projectile and a fuse are also provided.

Abstract: Ultrasonic ranging state management for a UAV is described. A transducer transmits an ultrasonic signal and receives an ultrasonic response thereto using a gain value. A noise floor estimation mechanism determines a noise floor estimate. A state mechanism sets an ultrasonic ranging state used by the transducer to a first ultrasonic ranging state. The transducer transmits an ultrasonic signal and responsively receive an ultrasonic response to the ultrasonic signal using a gain value according to the noise floor estimate. The state mechanism processes the ultrasonic response to determine whether to determine a new noise floor estimate, adjust the gain value used by the transducer, or change the ultrasonic ranging state of the UAV to a second ultrasonic ranging state. The configurations of the first and second ultrasonic ranging states differ as to, for example, power and gain levels used by the transducer to receive ultrasonic responses.

Abstract: The modulation scheme disclosed in this invention report allows for utilizing multiple 3D time-of-flight cameras at the same time by exploiting the inherent pseudo noise properties of the optical modulation signals. Compared to recent systems based on pure pseudo noise modulation signals, the stochastic measurement error in a single-camera environment is significantly reduced. The basic concept relies on the generation of a three level optical modulation signal that includes two pseudo noise sequences.

Abstract: A reflector is used to extend an aperture of an omni-directional, single-point remote-sensing echo-system utilizing secondary round-trip reflections of a transmitted sensor signal. The reflector is spatially displaced from a transmission element to contribute a secondary reflection whose echo from the target object provides additional information used to triangulate both azimuthal and elevation angles of the target object.

Abstract: Radar proximity fuse (1) adapted to receive an echo radar signal (s_rx) produced by the reflection on a target (T) of a transmitted radar signal (s_tx), the transmitted signal (s_tx) comprising a sequence of M impulses coded with a phase code (p_cd). The radar proximity fuse (1) comprising: a radiofrequency analog receiving front end (15) for receiving the echo radar signal (s_rx), adapted to provide in output a baseband signal starting from the echo radar signal (s_rx) received; an analog to digital converter (12) positioned at the output of the analog receiving front end (15) adapted to sample the baseband signal to obtain in output a sequence of digital samples (d_rx); a digital processing block (20) comprising a plurality of digital processing channels (C1, C2, . . . CN) each associated to a respective range gate and each adapted to receive in input said sequence of digital samples (d_rx).

Abstract: A proximity fuzing arrangement for fuzing warheads carried by missiles which reduces the likelihood of the missile being detonated prematurely by such cases as rain or enemy counter measures. The fuzing arrangement includes at least two channels responsive to target signals in different frequency bands and also includes means for comparing the signals in these channels to distinguish between spurious signals such as enemy counter measures or rain and so called “true target signals”.

Abstract: A projectile fuze sends a signal having encoded telemetry data. The telemetry data may be encoded by modulating an aspect or characteristic of the signal, such as frequency modulation of the signal. The fuze may receive and interpret reflections in order to determine proximity to a target or other object, such as by functioning as a height of burst sensor. The signal may include a series of random or seemingly random pulses (a keyed pattern of pulses), such as pulses in amplitude of the signal. The fuze includes a pair of transceivers for sending signals of different frequencies through an antenna, and for receiving signals through the antenna. The transceivers are configured such that one or the other is used at any one time when telemetry data is sent, with telemetry being encoded by changes in frequencies.

Abstract: A radar sensor is described that includes a radar transmitter, a radar receiver configured to receive reflected returns of signals output by the radar transmitter, and a signal processing unit configured to process signals received by the radar receiver. The signal processing unit includes a comparator, a first filter comprising an output coupled to a reference input of the comparator, and a second filter comprising an output coupled to a signal input of the comparator. The first and second filters are configured to receive a common input related to the reflected returns. The first filter is configured to have a time constant such that a rise time of the first filter output is faster than a rise time of the second filter output.

Abstract: The present invention is directed to a fuze application capable of GPS (Global Positioning System) and proximity radar functionality by co-locating a proximity radar antenna with a GPS DRA (Dielectric Resonator Antenna) fuze. The GPS DRA fuze has a HE11? mode structure resulting in an E-field null at the center. The monopole proximity radar antenna is mounted in the E-field null center and is thus electrically isolated from the GPS DRA fuze. The high dielectric constant permits the GPS DRA fuze to operate in the L1 frequency and the electrically shortened proximity radar antenna to resonate in the C-Band within a small form factor. The GPS DRA fuze maintains a forward-looking CP (circular polarization) pattern while proximity antenna maintains a desirable monopole pattern. Nesting allows mounting of both GPS and proximity radar antennas on the fuze nose while reducing the total space occupied.

Abstract: A system and method for passively estimating range and angle of a source are disclosed. The source may be any wave source including radio-frequency (RF), optical, acoustic or seismic sources. In some RF embodiments, the system includes a single aperture antenna to simultaneously receive RF signals from the RF source through a plurality of sub-apertures, and a signal processor to perform a proximity test using samples simultaneously collected from the sub-apertures to determine whether or not to calculate angle and range estimates to the source based on either a curved wavefront assumption or a planar wavefront assumption.

Abstract: A programmable circuit for controlling a detonation altitude of a radar equipped munition is provided. The circuit comprises means for calculating a velocity of the munition while the munition is operating in a pulse mode at an altitude greater than the desired detonation altitude and means, responsive to the means for calculating the velocity of the munition, for determining when the munition is at a reference altitude in order to operate the munition in a continuous wave transmission mode. The circuit further comprises means, responsive to the means for determining, for calculating a time representing when the vehicle will reach the desired detonation altitude based on the calculated velocity and the determined reference altitude, and means, responsive to the means for calculating the time representing when the vehicle will reach the desired detonation altitude, for generating a fusing signal to detonate the munition after the calculated time has passed.

Abstract: A radar processor for controlling detonation of a munition and operable to receive a detonation altitude from an external source is provided. The radar processor is configured to set a first range gate and a reference range gate based on the received detonation altitude, and cause a radar transmitter to operate in a continuous wave mode, for a predetermined period, upon receipt of radar return signals through the first range gate. The radar processor calculates a velocity of the munition from continuous wave return signals, and calculates a time delay for outputting a detonation signal based on the received detonation altitude, the calculated velocity, and a reference altitude of the munition, the altitude of the munition calculated based upon receipt of radar return signals through the reference range gate. The radar transmitter operates in a pulse mode while the munition is outside the reference range gate.

Abstract: A proximity fuze (proximity fuse) comprising an ultra wideband (UWB) radar transmitter, a UWB radar receiver, an antenna, a timing system, and a signal processor. One embodiment includes an antenna with an annular conical radiation pattern. In another embodiment, a trigger delay is produced that is related to target detection range. In a further embodiment, multiple range shells are utilized to further discriminate target characteristics including velocity. A method is disclosed that utilizes target range, velocity, signal amplitude, and radar signal phase to identify the target and trigger the detonation. A proximity fuze system having a long storage life is disclosed comprising a proximity fuze element powered by a turbine generator and internal gas source.

Abstract: A radar processor for controlling detonation of a munition and operable to receive a detonation altitude from an external source is provided. The radar processor is configured to set a first range gate and a reference range gate based on the received detonation altitude, and cause a radar transmitter to operate in a continuous wave mode, for a predetermined period, upon receipt of radar return signals through the first range gate. The radar processor calculates a velocity of the munition from continuous wave return signals, and calculates a time delay for outputting a detonation signal based on the received detonation altitude, the calculated velocity, and a reference altitude of the munition, the altitude of the munition calculated based upon receipt of radar return signals through the reference range gate. The radar transmitter operates in a pulse mode while the munition is outside the reference range gate.

Abstract: A method for controlling a detonation altitude of a radar equipped munition is described. The method includes calculating a velocity of the munition while the munition is at an altitude greater than the desired detonation altitude, determining when the munition is at a reference altitude, and calculating a time representing when the vehicle will reach the desired detonation altitude based on the calculated velocity and determined reference altitude. The method also includes generating a fusing signal to detonate the munition after the calculated time has passed.

Abstract: An ultra wideband radar system for detecting objects where at least one of the radar system or the object is moving. The radar may be scanned in at least one dimension, which may include angle or range. The system includes a scan combiner that combines scan information in accordance with a trajectory characteristic of a moving object and/or of a moving platform on which the radar resides. Scans may be combined by integration or filtering. A fast calculation method is described wherein the scans are combined into subsets and subsets are shifted in accordance with the trajectory characteristics before further combination. The scan information is combined in accordance with trajectory characteristics to enhance the object signal to noise. Further features are described wherein the scan information is combined according to a family of candidate trajectories and/or object positions.

Abstract: A radar sensor is described that includes a radar transmitter, a radar receiver configured to receive reflected returns of signals output by the radar transmitter, and a signal processing unit configured to process signals received by the radar receiver. The signal processing unit includes a comparator, a first filter comprising an output coupled to a reference input of the comparator, and a second filter comprising an output coupled to a signal input of the comparator. The first and second filters are configured to receive a common input related to the reflected returns. The first filter is configured to have a time constant such that a rise time of the first filter output is faster than a rise time of the second filter output.

Abstract: A system and method for passively estimating range and angle of a source are disclosed. The source may be any wave source including radio-frequency (RF), optical, acoustic or seismic sources. In some RF embodiments, the system includes a single aperture antenna to simultaneously receive RF signals from the RF source through a plurality of sub-apertures, and a signal processor to perform a proximity test using samples simultaneously collected from the sub-apertures to determine whether or not to calculate angle and range estimates to the source based on either a curved wavefront assumption or a planar wavefront assumption.

Abstract: A method and apparatus for guiding a vehicle to intercept a target is described. The method iteratively estimates a time-to-go until target intercept and modifies an acceleration command based upon the revised time-to-go estimate. The time-to-go estimate depends upon the position, the velocity, and the actual or real time acceleration of both the vehicle and the target. By more accurately estimating the time-to-go, the method is especially useful for applications employing a warhead designed to detonate in close proximity to the target. The method may also be used in vehicle accident avoidance and vehicle guidance applications.

Abstract: A unit is described that is configured to control detonation of a munition such that the munition is detonated at a desired altitude. The unit includes a radar transmitter, a radar receiver that includes a radar range gate, and a sequencer. The sequencer is configured to receive a detonation altitude and set the range gate based on the received detonation altitude. The unit is also configured to output a detonation signal when radar return pulses received by the receiver aligned with gate delay pulses from the range gate.

Abstract: A projectile launch detection system utilizes a continuous wave radio frequency signal (CW/RF) to confirm muzzle exit. The projectile launch detection system can be used in smoothbore, fin-stabilized, non-air breathing projectiles. The gun tube appears as a waveguide to the projectile launch detection system during projectile launch. The projectile launch detection system transmits a CW/RF signal down the gun tube during launch of the projectile. A portion of the CW/RF signal is reflected back by an impedance mismatch at the boundary between the muzzle of the gun tube and free space. Upon exit by the projectile from the gun tube, an exit signature is detected that is defined by the impedance of the gun tube and by a ratio of the diameter of the gun tube to the frequency of the CW/RF signal. The projectile launch detection system processes the exit signature to detect a muzzle launch of the projectile from a specific gun tube.

Abstract: A proximity sensor for use with a guidance system of a smart bomb including a ranging radar proximity sensor configured for mounting on a smart bomb and a radome connected to the ranging radar proximity sensor. A laser radiation sensor system is attached to the proximity sensor, which is configured and arranged to detect laser radiation reflected from a target which passes through the radome and output the azimuth and elevation angles to the target to the guidance system.

Abstract: A proximity fuze for use in a tube launched projectile carrying a payload, comprising an oscillator for generating a radio frequency signal which has a varying frequency, a single antenna for transmitting the radio frequency signal and for receiving an echo of the radio frequency signal, a first signal processor for generating a range signal corresponding to the time delay between the transmission of the radio frequency signal and the receipt of the echo signal, second signal processor for comparing the range signal with a reference signal and depending on the result of the comparison generating an activation signal for activating the payload, wherein a directional coupler is used for coupling the radio frequency signal from the oscillator to the antenna and to the signal processor and for coupling the echo signal from the antenna to the signal processor, and wherein the second signal processor comprises a threshold detector, a peak detector and a comparator, the threshold detector being for allowing the comp

Abstract: A fuzing system for non-spinning or substantially non-spinning weapons is implemented by means of wide angle optics providing at least forward-hemisphere coverage, an array of infrared detectors and a microprocessor for image and data processing, aim-point selection, directional-warhead aiming and skewed-cone fuzing. The skewed-cone fuzing has a generatrix which is the vector sum of missile velocity, warhead velocity and the negative of target velocity.

Abstract: An imaging fuse comprising a housing fixable within a receptacle at a fore end of a projectile, a coaxial support frame rotatably supported within the housing and fitted with an imaging assembly. The support frame is axially displaceable with respect to the housing. An axial shock absorbing system is provided intermediate the housing and the support frame, and a spin suppressing mechanism is associated with the support frame, for suppressing rotation of the support frame with respect to the housing.

Abstract: A radar system having a tactical mode and a calibration mode includes a transmitter section for providing high-power amplification of an RF pulsed waveform from an exciter during the tactical mode and the calibration mode. A circulator system has an input port connected to an output of the transmitter section and including first, second and third switchable junctions, and a high-power attenuator. The circulator system provides a transmit tactical mode signal path and a transmit calibration mode signal path of virtually identical electrical path lengths for a transmitter output signal, the tactical path passing through the first, second and third junctions in a first direction to an antenna I/O port, the calibration path passing through the first, second and third junctions in a second direction and through the high-power attenuator to an output port.

Abstract: An identification friend or foe system for use by a weapon to determine whether a target that has been selected is a friendly target comprises a signal source attached to the target and arranged to radiate encrypted signals. A detection system attached to the weapon includes a receiver arranged to receive the encrypted signals when the weapon is within a predetermined range from the target. Signal processing apparatus is connected to the receiver and arranged to determine whether the encrypted signals identify the target as being friendly. The central processing unit is arranged to decrypt the encrypted signal and produce a disarm signal if the target is identified as being friendly. The central processing unit preferably is also arranged to produce a signal that causes the weapon to perform a collision avoidance maneuver to avoid colliding with the target if the target is identified as being friendly.

Abstract: A method for guiding an intercepting missile to a body-to-body contact with an airborne target in the atmosphere. The method includes the steps of guiding the intercepting missile to within an appropriate distance from the airborne target, illuminating the airborne target, using an illuminator carried by the intercepting missile, acquiring an image of the illuminated airborne target and, steering the missile in accordance with an aimpoint on the image.

Abstract: An active short pulse fuze system for arming on a true target acquisition and firing only on the loss of the acquired target signal. The sea surface is tracked by means of a sea tracking loop A target threshold is established and is coupled to the sea tracking loop so as to expand and contract with the sea tracking. A return signal will pass the target threshold only when there is an abrupt reduction in range, indicating the presence of a target. The presence of this signal will arm the firing circuit. An abrupt increase in range will indicate the loss of the target and cause immediate detonation of the warhead.

Abstract: A signal processing circuit is disclosed for providing fuze-on-jam capability in a target detecting device, while in the presence of continuous wave or continuous wave noise jammer signals. A target detection system will protect the target detecting device from noise jammers and continuous wave radars or continuous wave jammers by providing a circuit which samples the negative or positive bias produced by the noise modulated CW signal and produces either positive or negative polarity as seen by the antenna. If negative pulses are produced, they will actuate the target detecting gate and guard circuit and after the missile has passed the critical angle of the antenna the phase change will then produce firing in the normal manner. The sampled output is fed into the target detecting mixing circuit and no interference with normal operations of the target detecting device occurs while a fuze-on-jam or CW capability is provided.

Abstract: An electronic circuit for a proximity sensor, which is target-independent and is based on a phase projection transformation, is configured in such a way that the oscillating circuit can be driven by a square-wave voltage. A synchronous demodulator is used for the phase projection transformation. The electronic circuit can be miniaturized and only low requirements are placed on the stability of the feed voltage. A method for operating a proximity sensor is also provided.

Abstract: A radar system (10) which transmits a random noise signal. The transmitted signal is embodied as an electromagnetic signal and is directed at an object or target. The object or target reflects at least a portion of the electromagnetic signal which is returned to the radar system. An image of the electromagnetic random noise signal is stored in memory (16) and compared with the returned modulated signal. Based on the correlation value, a determination is made regarding the object or target. In a particular implementation, the radar system is used in a target detection device (TDD) (10) in order to determine the distance from the target or object to the device and the relative velocity of the target or object and the device. When the target or object reaches a predetermined distance and also satisfies any other system requirements, the TDD (10) initiates a detonation signal which causes detonation of the missile or warhead.

Abstract: A fuzing system for non-spinning or substantially non-spinning weapons is implemented by means of wide angle optics providing at least forward-hemisphere coverage, an array of infrared detectors and a microprocessor for image and data processing, aim-point selection, directional-warhead aiming and skewed-cone fuzing. The skewed-cone fuzing has a generatrix which is the vector sum of missile velocity, warhead velocity and the negative of target velocity.

Abstract: A target detection device of the electromagnetic transmitter-receiver reaction type comprising a radio frequency oscillator which is integral with its radiating system and detector. It incorporates a pulse modulator which drives the oscillator to periods of high power transmission and a signal processing system to reject unwanted data and to effect detonation of the warhead at the optimum point on its trajectory.

Abstract: The distance sensor for projectile fuzes, according to the invention, employs a range finder (6', 17, 25, 27) operating on the principle of pulse propagation time. The signal (18) is radiated by an antenna (4, 5') and the portion (18') reflected by the target is also received thereby. From a pulse (17') derived from the transmitter pulse and delayed in time by a definite amount in the delay member (19), one obtains the receiver sampling pulse (20). This pulse is used to sample the portion (18') and the resulting low-frequency representation of the receiver pulse is passed through a low-frequency amplifier (21) and a band-pass filter (44).

Abstract: A proximity fuze radar system is described including a transmitter for transmitting a signal modulated by a pseudo-random noise code signal and a receiver for receiving signals including the modulated signal reflected by an object or target. The proximity fuze radar system further includes delay circuitry for delaying in time the pseudo-random noise code signal for providing a delayed noise code signal and circuitry for correlating a near range portion of the received signals with the delayed noise code signal and for providing base band signals. The proximity fuze radar system still further includes suppression circuitry for correlating a longer range portion of the received signals with the delayed noise code signal and for providing a rejection signal for summing the base band signals with the rejection signal to reduce the signal level of undesired signals. With such an arrangement, a radar system is provided having less susceptibility to undesired signals.

Abstract: A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range.

Abstract: System and modifications are presented which allow existing artillery and rtar projectile proximity fuzes to have a near-surface burst (NSB) option enabling low height of bursts ranging between one and three meters. The additional circuitry needed to implement this NSB into an existing fuze is a single operational amplifier. The velocity of the fuze is calculated by the micro-controller counting the number of Doppler cycles over a pre-determined sample period of time. Thereafter, using the fuze velocity, the delay time needed for a NSB detonation is computed.

Abstract: A proximity detonator which derives its firing criterion from reflected beam measurements and thus obtains information about the radial relative velocity of the detonator with respect to its target object by evaluating the Doppler effect, wherein the firing signal is produced by a circuit including a function generator whose output voltage has a time sequence which corresponds to the decrease in radial relative velocity as the detonator approaches its target object (possibly under consideration of a correction value resulting from the firing law), a voltage controlled oscillator whose control input is connected to the output of the function generator, and a phase comparator having two signal inputs, one of which receives a Doppler signal which corresponds to the radial relative velocity and the other of which is connected to the output of the oscillator.

Abstract: A pulse Doppler proximity sensor uses a plurality of stepped output radio signals for accurately determining the relative range between the proximity sensor and an object. A dual modulation technique is employed which incorporates a pulse modulation arrangement and a carrier frequency modulation arrangement to detect the necessary range accurately from the plurality of output radio signals. The proximity sensor processes in parallel each of the plurality of output radio signals returned from the object. A binary comparison is made and the comparison is integrated over time to prevent false alarms. The pulse Doppler proximity sensor is particularly useful in fuzing arrangements for a munition in which a number of range settings are desired.

Abstract: A self telemetry system for use on missiles that utilizes the existing on board fuze transmitter as a telemetry transmitter.

Abstract: A sensor arrangement for an active member, especially such as a landmine which is deployed against ground and airborne target objects, including a waking or proximity sensor which is responsive to the approach of a target object. A high degree in the precision of direction-finding, in addition to target classification; can be achieved by means of a larger passive bearing or direction-finding base, such as can be set up through the positioning of at least three microphones about the mine or at a certain distance from the mine. Hereby, such a passive acoustic direction-finding or bearing base evidences the advantage in contrast with essentially the active high-frequency direction-finding, in that the mine cannot be located from the target object and thus is able to remain in constant operation upon the activation of a waking or proximity sensor without any danger of the mine having its presence betrayed.

Abstract: An underwater maneuverable vehicle is presented which carries an explosive charge and can be used for immediate removal or destruction of various menaces to navigation and other underwater hazards. The battery powered vehicle is air dropped from a platform which carries an imaging lidar system for detection and is operated and navigationally controlled in conjunction with an imaging lidar system. In accordance with an important feature of this invention, an optical lidar downlink is used to control the submerged underwater maneuverable vehicle from an airborne platform. The downlink is pulse spaced modulated. Command signals are secure, and are decoded aboard the vehicle. Control in speed, heading and depth, as well as command detonation are available using this technique.

Abstract: An open loop proximity detector is contemplated which receives a Doppler frequency when a target is first detected, and predicts a specific fuzing Doppler frequency. The detector continues to transmit and receive electromagnetic waves and sends a detonating signal to the fuze when the predicted fuzing Doppler frequency is received by the detector. The Doppler frequency of the first, or front surface in a forward moving direction of the target is received and is used to detonate the fuze. Thus the ideal surface of the target, the front surface, detonates the fuze and Doppler frequencies from other surfaces of the target are not allowed to interfere with the detonating process.

Abstract: A method and apparatus for determining an altitude for a radar fuze. The method includes the steps of receiving a return signal and transmitting a transmitted signal. The return signal and the transmitted signal are mixed and a mixed signal representing an altitude is responsively generated therefrom. The mixed signal is amplified to generate an amplified signal. The amplified signal is filtered to generate a filtered signal which is envelope detected to provide a detected signal responsive to the filtered signal. The detected signal is integrated responsively to the detected signal. The integrated signal level is compared against a track threshold reference signal and a track/no-track comparator signal is provided responsively to the integrated signal level and the track threshold reference signal. System timing is controlled by generating a plurality of control signals responsive to the track/no-track comparator signal and proportional to an altitude.

Abstract: A munitions cartridge transmitter capable of emitting an electromagnetic signal after discharge from a cartridge propelling device comprises a signal generator, an electromagnetic signal transmitter coupled to the generator, an antenna coupled to the transmitter, and a hollow cartridge for housing the generator, the transmitter, and the antenna. The transmitter is energized after discharge of the cartridge propelling device by a power source contained in the cartridge.

Abstract: A method for activating a mine possessing a specified activation radius; in particular an anti-helicopter mine, which is brought into an alarm condition by acoustic signals. In the alarm condition of the mine, an NLOS-radar is activated, through which the target speed and the target range of a helicopter are detected and the result of the detection is compared with the specified activation radius of the mine. Full activation of the mine is then implemented when the detection result is smaller than the activation radius, or a further or renewed NLOS-radar detection is effected when the detection result is greater than the activation radius of the mine.

Abstract: A random binary modulated sensor transmits a continuous wave r.f. signal ulated by a binary random bit pair code signal which is transmitted by an antenna. A return signal reflected from a target is received by the antenna. A receiver mixer modulates the return signal with the r.f. signal and a delay circuit delays the binary random bit pair code. A coorelator receives the modulated return signal and delayed binary random bit pair code for producing a doppler output signal. A separate r.f. path in which a portion of the modulated r.f. signal is variably attenuated and variably phase shifted is present to cancel noise signals generated by antenna mismatch in transmission.

Abstract: A voltage controlled oscillator is disclosed in a "ring" configuration using two BJTs. The design uses an active feedback topology which eliminates the need for a tank circuit for oscillation to occur. The design also provides for the mixing function to be performed by one of the BJTs.