Abstract: In accordance with one aspect of the present invention, a method is provided for calibrating an aircraft surveillance system for a protected aircraft. The system has a phased antenna array comprising antenna elements. The method comprises transmitting a first signal from a first antenna element in the array, and receiving the first signal at a third antenna element. The first signal may represent an interrogation signal transmitted in connection with a surveillance transmit sequence to locate potential intruding aircraft into a range of the protected aircraft. The method further includes transmitting a second signal from a second antenna element and receiving the second signal at the third antenna element. The method also includes calculating calibration information for the antenna array based on the first and second signals received at the third antenna element. During each transmit operation only a single antenna element transmits at one point in time.

Abstract: An aircraft electronics system is provided that includes a radar system, a display, an embedded global positioning/inertial navigation system (EGI) and a processor. The radar system is configured to generate aircraft operational data. The display is configured to display the aircraft operational data. The EGI is configured to generate aircraft behavior components and the processor configured to override the aircraft operation data displayed on the display when at least one of the aircraft behavior components is beyond a defined limit, wherein potentially incorrect aircraft operational data affected by at least one of the aircraft behavior component is not displayed.

Abstract: An aircraft radar system includes a radar antenna and a processing device. The processing device receives returns from the radar antenna associated with the scan. The processing device uses the returns from the scan for use in both incursion detection and weather phenomenon detection. A method for using the returns from the scan for both incursion detection and weather phenomenon detection is also disclosed.

Abstract: A system and method for target classification for an aircraft surveillance radar is provided. In one implementation, the track classifier provides tracks with an updated probability value based on its likelihood to conform to aircraft and non-aircraft target behavior. The track classifier identifies false tracks that may arise from weather and biological targets, and can detect aircrafts lacking Secondary Surveillance Radar (SSR) data. Various features and combinations of features are evaluated using a proposed clustering performance index (CPI) and used to discriminate between aircrafts and false tracks.

Abstract: A correlation processor for a receiver is capable of carrying out a correlation process with highly suppressed side lobes, improved resolution, and minimized S/N loss. The correlation processor is provided for a receiver that receives a signal having a specific time width and shape, for carrying out a correlation process on the received signal. The correlation processor has a filter coefficient unit to calculate a coefficient vector that zeroes sample values of all sample points except a peak center sample point of a main lobe of a correlation-processed waveform of the received signal and sample points on each side of the peak center and minimizes S/N loss of the sample value of the peak center sample point of the main lobe and a filter to carry out a correlation process on the received signal according to the coefficient vector calculated by the filter coefficient unit.

Abstract: A radar sensor and a corresponding method for distance and cruise control of a vehicle are described; using this sensor and method, objects in front of the vehicle in the direction of travel are detected and at least the variables: distance, relative velocity, and azimuth angle of the detected objects are ascertained with regard to the vehicle, the change over time of the reflection point of the radar beam on the object and classification of the detected object being determined as a function of the change over time of the reflection point.

Abstract: In an aircraft-mounted Doppler radar clutter rejection system, a flexible, sharp band pass filter uses Taylor weighting, an FFT and a module for selecting which of the Doppler cells are to be activated, thus to control the band pass characteristic and set the clutter line to the speed of the aircraft.

Abstract: In a radar system, a monopulse calibration table is constructed from live targets of opportunity. A center of gravity or weighted average of normalized signals ?V received at SUM and DIFF channels from a live target are used to determine the target's actual azimuth. Off bore sight angles (OBA) of the target are then determined from the target's actual azimuth. Normalized received signal values of ?V are converted to nearest-valued integers. The OBA s that correspond to each integer-valued normalized received signal are averaged and can then be plotted as a function of normalized received signal value ?V. Different tables or plots can be constructed for elevation angles. An equation of a best-fit line the matches or at least closely approximates the plotted data is determined to smooth the actual data.

Abstract: A ground-penetrating radar comprises a transmitter for launching pairs of widely separated and coherent continuous waves. Each pair is separated by a different amount, such as 10 MHz, 20 MHz, and 30 MHz. These are equivalent to modulation that have a phase range that starts at 0-degrees at the transmitter antenna which is near the ground surface. Deep reflectors at 90-degrees and 270-degrees will be illuminated with modulation signal peaks. Quadrature detection, mixing, and down-conversion result in 0-degree and 180-degree reflections effectively dropping out in demodulation.

Abstract: A method of delaying propagation of a radio frequency (RF) signal through a circuit is described. The method comprises receiving data that represents a delay time interval, providing an RF signal when a start pulse triggers a memory device, initiating a count through the delay time interval based on receipt of a start pulse, and outputting the RF signal after the delay time interval has expired.

Abstract: Without using a traveling velocity of a vehicular object mounted with a radar device, an off-axis angle which is an offset angle between a reference direction of the radar device and a traveling direction of the vehicular object is estimated.

Abstract: A radar apparatus is provided which correctly combines and displays detected data obtained from a plurality of radar antennas. Detected data obtained from a radar antenna 11 is subjected to a correlation process in a correlator 91A. Detected data obtained from a radar antenna 21 is subjected to a correlation process in a correlator 91B. A mask image which designates the same address as that of the correlated data from the radar antenna 21 is set by a mask area generator 32 and is written into a mask image memory 62. For the correlated data from the correlators 91A and 91B, addresses corresponding to installed positions of the radar antennas 11 and 21 are set. For a process image memory 902B of the correlator 91B and the mask image memory 62, a common address is set. Correlated data input in accordance with mask data is stored in a display image memory 61 in accordance with an address set in a display screen and is also output to a display device 10.

Abstract: A computer system for decompressing synthetic aperture radar (SAR) images includes a database for storing SAR images to be decompressed, and a processor for decompressing a SAR image from the database. The decompressing includes receiving the SAR image, performing a dynamic range compression on the SAR image, and quantizing the compressed SAR image. The quantized compressed SAR image is then decompressed by applying an anistropic diffusion algorithm thereto.

Abstract: A time-reversal imaging radar system for acquiring an image of a remote target includes an antenna array having a plurality of spaced-apart antennas, and a transceiver coupled to the antenna array for alternately transmitting a radar signal via the antenna array toward the target and for receiving target-reflected radar signals. The transceiver includes means for multiple-pass time-reversing the transmitted and received radar signals whereby coherent beam focusing is realized at both the target and at the receiver to thereby enhance the resolution of the acquired target image.

Abstract: Methods and systems for using ground penetrating radar (GPR) to obtain subsurface images. The depression angle, frequency, and polarization can all be adjusted for the soil conditions at hand. In particular, the depression angle is set at the “pseudo-Brewster angle” for improved ground penetration.

Abstract: A radar apparatus including units for transmitting and receiving an electric wave to detect a target, a unit for detecting wave interference caused by surroundings, a unit for controlling the modulation state of the transmitted wave, a communication unit for acquiring modulation state information being used by the other radar apparatuses, and a unit for selecting such a modulation state as to avoid interference with the modulation state information when the wave interference detecting unit detects the wave interference.

Abstract: A radar device has a long range radar sensor having a first transmission and receiving section for transmitting and receiving radio wave to a first detection range and a first signal processing section for detecting an object existing in the first detection range; a short range radar sensor having a second transmission and receiving section for transmitting and receiving a radio wave to a second detection range of which width is wider and of which distance is shorter than the first detection range and a second signal processing section for detecting an object existing in the second detection range; and a processing section for integrating information supplied from the first and second signal processing sections. And one of the long range radar sensor and the short range radar sensor stops a detection operation of the object to an overlapped range of both the detection ranges.

Abstract: Disclosed is a distance measuring system comprising a transmitter that sequentially generates pulse sequences each having a plurality of pulse signals of equal amplitudes arranged at equi-time intervals, and transmits the generated pulse sequence as a radio wave; and a receiver that receives the pulse sequence transmitted from the transmitter as a radio wave, and has a distance calculator that acquires propagation times of the pulse signals in the received pulse sequence, and calculates a distance from the transmitter by giving different weightings to the pulse signals for the propagation times acquired for the respective pulse signals. As the amplitudes of the pulse signals in the received pulse sequence become larger, the weightings are made larger.

Abstract: Disclosed is a Mode S radar which specifies an aircraft by transmitting interrogations to an aircraft A equipped with a Mode S transponder, and by then receiving and decoding replies corresponding to these interrogations. In the Mode S radar, detection reports on the aircraft A are generated in a manner that: for a Mode A code necessary for generating detection reports, when identicalness between the Mode A codes obtained in a plurality of scans after the initial acquisition of the aircraft A has been found to exist, the Mode A code thus found identical is adopted without carrying out a Mode A code interrogation (UF=5) thereafter. Accordingly, the Mode S secondary surveillance capable of generating more highly reliable detection reports is achieved.

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.