Matches 201 - 250 out of 371 < 1 2 3 4 5 6 7 8 >
Match Document Document Title
5175558 Nulling system for constraining pulse jammer duty factors  
An adaptaive nulling antenna control system (24) which is effective in constraining pulse jammer duty factors. The system (24) accepts signals from a multibeam antenna (40) in a coded communication...
5142291 Passive microwave near-field tomographic imaging system and method  
A technique for near-field tomographic imaging using a multiple-receiver correlating interferometer. A target object or scene to be imaged is located in a near-field or Fresnel region of a receiver...
H001033 Anti-jamming system for tracking and surveillance radar  
A radar ECCM system for degrading the effect that a standoff noise jammer has on a radar receiving site that is tracking an incoming aerial target. The system effectively removes from the mainlobe...
5081461 Correlation detector for FM signals  
Apparatus for detecting FM signals, such as from a radio altimeter, is disclosed. The apparatus contains a phase detector which has as inputs the received signal and a delayed replica of the input...
H001005 Gram-Schmidt space-time adaptive filter using transverse orthonormal ladder filters  
A space-time adaptive filter system is provided for eliminating unwanted signals from a radar or communication system. The filter system receives a main channel and several auxiliary channels...
5049890 Sampled data processing  
An improved signal processing system and technique for preprocessing auxiry data signals by sequential decorrelation, particularly for use in systems employing adaptive cancaller loops. Each of a...
5041836 Self-steered antenna system  
An antenna system determines the true time delay in two or more correlated signals without a priori knowledge of the time relationship between the signals and uses the determined true time...
5017929 Angle of arrival measuring technique  
An improved angle of arrival measurement technique for monopulse antenna systems employing phase shifters on each of the four feeds to resolve ambiguities and to increase the beam splitting (angle...
4991147 Preformed beam tracker  
Apparatus and method for sonar or radar target tracking. Digital apparatus nd techniques are employed. A variable delay is used for beam steering.
4947177 Narrow band correlator and noise cancellor  
A narrow band noise cancellor and signal correllator which obtains an increased signal to noise ratio of a received signal from a multi sensor array; the resulting output signal is at double the...
4937584 Adaptive phase-shifter nulling techniques for large-aperture phases arrays  
A method of nulling out interference sources in a large-aperture phased ay radar system is described. The system has apriori knowledge of the interference sources and depends upon access to the...
4931977 Vectorial adaptive filtering apparatus with convergence rate independent of signal parameters  
An adaptive signal processor, used for discriminating between a desired signal and several undesired signals, includes an arrangement of sensors, which samples the signals and forms a set of...
H000741 Discrete complex correlation device for obtaining subpixel accuracy  
This invention is directed to an image processing arrangement used to estimate image displacement relative to a reference frame. It comprises a discrete complex correlator, an associated...
4864309 Microwave radiometer  
A microwave radiometer is formed of a set of frequency scanning antennas disposed parallel to each other and connected by a common microwave feeder. Signals of individual ones of the antennas are...
4857937 Data element position indication  
In, for example, a passive direction-finding radio receiver employing a multi-beam antenna which has e.g. ninety-six feeds which form a corresponding number of overlapping reception beams, the...
4813006 Analog-digital correlator  
An analog-digital correlator 10 utilizes a plurality of sample and hold cirucits 16-0 to 16-(M-1) to directly store samples of a received analog signal. Bits of a correlation pattern are shifted...
4806939 Optimization of convergence of sequential decorrelator  
A sequential decorrelator arrangement for an adaptive antenna array comprising a plurality of antenna elements the outputs of which feed a cascaded beamforming network having a succession of...
4801941 Angle of arrival processor using bulk acoustic waves  
A bulk acoustic wave angle-of-arrival processor in which a bulk acoustic body having the property of conducting bulk acoustic wave beams has formed and defined thereon at acoustically reflecting...
4771289 Beamforming/null-steering adaptive array  
A beamforming adaptive control loop is simultaneously employed in combination with a null-steering adaptive control loop to enhance the signal/interference ratio resulting in an increase in the...
4757319 Adaptive depolarization-interference-compensator  
An adaptive depolarization-interference-compensator for a digital radio relay system using multi-level quadrature amplitude modulation (QAM) with co-channel operation of the orthogonally polarized...
4754282 Improved data analysis system  
A data analysis system accepts time related data samples which are develo from sets of common wavefronts incident upon a plurality of sensors. The data samples are converted from analog-to-digital...
4734701 Null processing receiver apparatus and method  
A null processing receiver apparatus that receives and combines together a number of modulated information signals in such a fashion that an interference or jamming signal superimposed on each...
4717919 Feedback limited adaptive antenna with signal environment power level compensation  
An adaptive antenna comprising at least two sensors for receiving electromagnetic signals and for producing first signals; the antenna further including divider means for dividing each first signal...
H000374 Optimum multiple target detection and resolution  
A method or technique of resolving multiple energy sources from signals oined by a spatial array of sensors in which portions of two prior art techniques are combined to yield an improved hybrid...
4665400 Method and apparatus for radar surveillance  
In a method and an apparatus for radar surveillance a multilobe antenna is commonly used for transmission as well as reception and distributes the power (P) to be radiated in several (n)...
4654667 Signal-acquisition system for a circular array  
A signal-acquisition system (10) for a circular antenna array (12) includes a two-dimensional compressive receiver (18) that performs a two-dimensional Fourier transformation in time and position...
4651155 Beamforming/null-steering adaptive array  
A beamforming adaptive control loop is simultaneously employed in combination with a null-steering adaptive control loop to enhance the signal/interference ratio resulting in an increase in the...
4641143 Two-dimensional acquisition system using circular array  
A frequency-and-direction-finding system (10) employing a circular array (12) performs a two-dimensional Fourier transformation in space and time on the signals from the individual elements. The...
4633257 Acquisition system employing circular array  
A system for indicating the direction of a source of radio waves received by a circular antenna array (12) includes a Butler matrix (18) that receives the array outputs and feeds the resultant...
4625211 Adaptive antenna array  
A multiple output, power inversion adaptive antenna array comprises a number of antenna elements A1-An feeding a cascade beam former structure having groups of decorrelation stages D1 1 -D1 n -1,...
4606067 Device for recognizing far-away electro-magnetically radiating objects  
The device operates after the principle of an intensity interferometer. It contains a plurality of detectors arranged two-dimensionally in fixed relative positions. The signals from the detectors...
4594593 Synthetic aperture radar image processing system  
In an SAR image processing system of the type wherein an image is reproduced from received data, the reproduced image is obtained on the basis of range compression, range curvature compensation and...
4577309 Method and apparatus for measuring distant echo delay in an echo cancelling arrangement  
Method and apparatus for measuring the delay of the distant echo in an echo ancelling arrangement comprising a near echo canceller, a delay line and a distant echo canceller using the steps of ...
4561067 Multi-channel cross-talk interference reduction circuit using modulation-multiplying-demodulation correlator  
A circuit for cancelling unwanted components in two received signals has a first input for one of the signals and a second input for the other. The first input is connected by a first circuit path...
4528674 Method and apparatus for baseband generation of a spread spectrum reference signal for use in an LMS adaptive array processor  
A method and apparatus for baseband generation of a spread spectrum reference signal for an LMS adaptive array processor is provided. An IF summed, weighted spread spectrum signal is output from...
4489326 Time reference scanning beam microwave landing system  
The disclosure teaches a method, and an apparatus for carrying out the method, for determining the time between TO and FRO received waveforms from the time reference scanning beam (TRSB) of a...
4443801 Direction finding and frequency identification method and apparatus  
A surface acoustic wave interferometer direction finding and frequency idification method and apparatus is disclosed. The invention utilizes a plurality of dispersive delay lines in order to...
4442433 Adaptive signal processing apparatus  
An array of signals is adapted and dithered by use of a weight signal, a gradient signal with a carrier at a first frequency and an orthogonal sequence signal with a carrier at a second frequency,...
4438530 Adaptive cross-polarization interference cancellation system  
Separate components of a received signal are transmitted along two distinct paths to the adaptive cross-polarization interference cancellation arrangement. In each path, appropriate circuitry...
RE31509 Echo location systems  
This invention generally relates to echo location or ranging systems in which the individual properties of targets or reflectors (such as range, bearing, elevation angle, relative velocity,...
4423419 Pulsed, pseudo random position fixing radio navigation method and system and the like  
This disclosure is concerned with a technique and apparatus for reducing CW and other inband interference in a broad bandwidth RF pulse navigation system to inobtrusive noise through the use of...
4371946 Servomechanism for doppler shift compensation in optical correlator for synthetic aperture radar  
A method and apparatus for correcting doppler shifts in synthetic aperture radar data. More particularly, in an optical correlator (10) for synthetic aperture radar data having a means for...
4371873 Clutter free synthetic aperture radar correlator  
A synthetic aperture radar correlation system including a moving diffuser located at the image plane of a radar processor. The output of the moving diffuser is supplied to a lens whose impulse...
4320400 Method and apparatus that nearly instantaneously samples, processes and sorts received signals from very large numbers of radar and radio emitters for frequency and angle of arrival analysis  
A method and apparatus is described that processes, samples and sorts, for subsequent analysis, very large numbers of randomly arriving pulsed and continuous wave radio and radar signals, while...
4317118 Symmetrical beam-forming network  
A beam-forming network having zero boresight error comprising a network hng symmetry about the network centerline.
4293945 Multichannel correlation receiver for determining depolarization of signals along signal propagation paths  
A multichannel correlation receiver at an earth station is provided for determining the depolarization effects of atmospheric conditions on satellite communications. The receiver provides a first...
4285048 Space variant signal processor  
A correlation method and apparatus for electrical signal transmission and ception of coded waveforms are disclosed which makes use of a coordinate transformation of the original waveform prior to...
4282589 Correlation ranging  
1. In sonic ranging the method which comprises transmitting a first sonic pulse having a predominant frequency in the upper sonic range, transmitting a second sonic pulse after a time delay...
4270180 Delay line time compression correlation circuit  
A delay line time compression correlation circuit for correlating two sets of serial data is disclosed, and includes a counter for defining the number of data pairs that have been correlated and...
4255791 Signal processing system  
An adaptive array signal processing system employs a correlation discriminant operator or signal recognizer. The operation of the signal recognizer is dependent upon noise decorrelation rather than...
Matches 201 - 250 out of 371 < 1 2 3 4 5 6 7 8 >