Abstract: A satellite communications method for communicating information from a base station, via a satellite, to one or more user terminals via a single channel of a forward link.

Abstract: An imaging system (50) for providing vehicle security and convenience features that employs face recognition software to identify and track a person. The system (50) employs infrared emitters (30) that emit an infrared signal along a predetermined field-of-view, and an infrared sensor (34), such as a CMOS sensor used as a video signal array, that receives reflected infrared illumination from objects in the field-of-view. A processor (52) including the face recognition software, is employed to detect human faces to identify and track the person. Once a face is detected, it can be compared to a data base to identify the person.

Abstract: A method beginning at (10) is provided for creating high-fidelity visible coloring from infrared images of a scene under surveillance. The infrared images captured at (12) are analyzed at (14) to determine if an object, such as a face, is identifiable within the image. If an object is identifiable at (16) the object features are compared to a plurality of stored object features at (20). If there is a match at (22), the color characteristics of the object are obtained at (24) and the object is colored at (26) based on the stored database feature information. If there is no match at (22) or identifiable object at (16) and object color cannot be identified at (23), the image is analyzed at (28) to determine if a pattern, such as clothing, is identifiable within the image. If a pattern is identifiable at (30), the color characteristics of the pattern are obtained at (34) and the pattern is colored at (36) according to infrared reflectance characterization in conjunction with the stored pattern information.

Abstract: A communication system for mobile platforms includes mobile platforms with transceivers identified by Internet Protocol (IP) addresses. A satellite relays a forward link from a ground station to the mobile platforms. The forward link contains IP packet data that is modulated by variable length orthogonal (VLO) spreading codes and that has different information data rates. The VLO spreading code for each IP packet is selected to optimize a desired link margin of the IP packet that is received by the addressed transceiver. The IP packets can also be modulated using a pseudonoise (PN) spreading code. Forward error correction (FEC) may also be applied. The transceivers include a feedback circuit that generates an Eb/No estimate.

Abstract: A vehicle occupant airbag deployment system (50) that detects, identifies and tracks a person (16) in the passenger seat (18) of a vehicle (12), and provides a signal for no fire, soft fire or hard fire of the airbag (20) depending on the location of the person (16) in a crash event. The airbag deployment system (50) employs infrared emitters (30) that emit an infrared signal towards the passenger seat (18) of the vehicle (12) and an infrared detector (34) that receive reflected radiation from objects in the seat (18). Processing circuitry (52), including face recognition software, is employed to detect human face features to provide the necessary detection and tracking of the person (16).

Abstract: A human presence detection system (50) that employs a frame differencing technique for subtracting out background interference from images generated by the system. The system (50) includes an infrared source (28) that generates a beam of infrared radiation, and an infrared detector (72) that receives infrared radiation reflected from objects in the path of the beam. Face recognition software is employed to determine the presence of a person (16) from the reflected radiation. The infrared source (28) is pulsed on and off and the detector (72) is synchronously shuttered to the pulses so that image frames are generated at different times, where one frame includes reflected radiation and background radiation and another frame includes only background radiation. The frames are subtracted to separate out the background radiation.

Abstract: A method beginning at (10) is provided for creating high-fidelity visible coloring from infrared images of a scene under surveillance. The infrared images captured at (12) are analyzed at (14) to determine if an object, such as a face, is identifiable within the image. If an object is identifiable at (16) the object features are compared to a plurality of stored object features at (20). If there is a match at (22), the color characteristics of the object are obtained at (24) and the object is colored at (26) based on the stored database feature information. If there is no match at (22) or identifiable object at (16) and object color cannot be identified at (23), the image is analyzed at (28) to determine if a pattern, such as clothing, is identifiable within the image. If a pattern is identifiable at (30), the color characteristics of the pattern are obtained at (34) and the pattern is colored at (36) according to infrared reflectance characterization in conjunction with the stored pattern information.

Abstract: An improved method for performing cyclic redundancy check (CRC). The present invention condenses a plurality of CRC sequences into a single reduced bit count CRC equivalent. The number of bits occupied by the reduced bit count CRC equivalent is fewer than the number of bits occupied by the individual CRC sequences. Thus, the present invention reduces the number of bits required to perform the CRC operation, thereby increasing the number of bits available for transporting information data bits.

Abstract: An improved method for performing cyclic redundancy check (CRC). The present invention condenses a plurality of CRC sequences into a single reduced bit count CRC equivalent. The number of bits occupied by the reduced bit count CRC equivalent is fewer than the number of bits occupied by the individual CRC sequences. Thus, the present invention reduces the number of bits required to perform the CRC operation, thereby increasing the number of bits available for transporting information data bits.

Abstract: An imaging system (50) for providing vehicle safety features that employs face recognition software to identify and track a person. The system (50) employs infrared emitters (30) that emit an infrared signal along a predetermined field-of-view, and an infrared sensor (34), such as a CMOS sensor used as a video signal array, that receives reflected infrared illumination from objects in the field-of-view. A processor (52) including the face recognition software, is employed to detect human faces to identify and track the person. Once a face is detected, it can be compared to a data base to identify the person. Various applications for the imaging system (50) for providing vehicle safety features include identifying the driver or passenger for personalizing the vehicle's airbags, providing pre-crash collision avoidance, providing blind spot detection, providing vehicle crash recording, and providing a warning signal if the driver appears drowsy.

Abstract: A digital Intermediate Frequency (IF) QAM receiver 300 is provided which yields an improved SNR. The digital IF QAM receiver 300 eliminates the integration step (260, 265) and low pass filters (250, 255) of a standard digital QAM receiver 200. Instead, the digital IF QAM receiver 300 mixes the received signal with a an intermediate frequency (IF) local oscillator (LO) 325. After mixing with the IF LO 325, each channel is band pass filtered (355, 357), and then converted from analog to a digital signal (360, 362). The digital signal is then demultiplexed (365, 367) into a plurality of streams of digital pulses. The stream with the maximum average power is then selected by a select stream processor (370, 372). The selected stream is time aligned to conform to a symbol period by a stream timing alignment processor (375, 377). The aligned stream for both the I and Q channels is sent to a maximum likelihood decision mapping processor 390 which determines the respective bit code.

Abstract: A communication system for mobile platforms includes mobile platforms with transceivers identified by Internet Protocol (IP) addresses. A satellite relays a forward link from a ground station to the mobile platforms. The forward link contains IP packet data that is modulated by variable length orthogonal (VLO) spreading codes and that has different information data rates. The VLO spreading code for each IP packet is selected to optimize a desired link margin of the IP packet that is received by the addressed transceiver. The IP packets can also be modulated using a pseudonoise (PN) spreading code. Forward error correction (FEC) may also be applied. The transceivers include a feedback circuit that generates an Eb/No estimate.

Abstract: An enhanced Doppler type direction finding system uses two antennas or antenna pairs (1 & 7) that are rotated in two mutually orthogonal circular paths (8 & 13) to intercept incoming RF from an emitting source, whose direction is to be determined.

Abstract: A method of optimizing data compression in a data compression process. A single compressor is provided for performing video signal data compressor operations (122). The compressor receives a video signal that includes spatial and temporal data from a plurality of video signal frames. The compressor performs motion compensation (124, 126) on the plurality of video frames by simultaneously registering the plurality of video signal frames to produce a plurality of motion vectors. A performance metric including energy compaction parameters is then generated from the plurality of motion vectors (128). The performance metric is applied to the motion compensation step (124, 126) to optimize rate distortion performance in the motion compensation step and in subsequent data compression process steps.

Abstract: Methods for compressing digital video signals that fully utilize temporal compression techniques. Each of the methods disclosed compresses digital video signals not only in the spatial domain, as with current implemented MPEG compression methods, but also in the temporal domain. A group of video signals is input to a signal compressor (16). The signal compressor (16) performs discrete cosine transforms in both the spatial and temporal domain. The transformed data is then input into a three-dimensional quantization matrix (18), where rate and distortion optimization parameters are calculated for compression purposes. In a first method, rate-distortion performance and transmission order are optimized for the quantized, three-dimensional transform coefficients. In a second method, rate-distortion performance is optimized for the quantized, three-dimensional transform coefficients.

Abstract: Methods for compressing digital video signals that fully utilize temporal compression techniques. Each of the methods disclosed compresses digital video signals not only in the spatial domain, as with current implemented MPEG compression methods, but also in the temporal domain. A group of video signals is input to a signal compressor (16). The signal compressor (16) performs discrete cosine transforms in both the spatial and temporal domain. The transformed data is then input into a three-dimensional quantization matrix (18), where rate and distortion optimization parameters are calculated for compression purposes. In a first method, rate-distortion performance and transmission order are optimized for the quantized, three-dimensional transform coefficients. In a second method, rate-distortion performance is optimized for the quantized, three-dimensional transform coefficients.

Abstract: A semiconductor light-emitting device structured similarly to an index-guided laser, but having waveguide channels that are formed at a selected small angle of inclination with respect to a direction normal to cleaved facets formed in the structure. The angle of inclination should be at least half the critical beam angle above which total internal reflection will not occur within the waveguide channels. The angled condition of the waveguide channels ensures that effective mirror losses at the facets exceed the modal gain of the device, so that lasing will not occur, even when the current and power are increased to high levels. The device produces up to 30 mW or more of output power at a large spectral bandwidth and small coherence length.

Abstract: A superluminescent light-emitting diode in which the spectral width of the output increases with increasing optical output power, thereby allowing the generation of high optical output powers with a broad frequency spectrum that is desirable for some applications of the superluminescent diodes. This desirable characteristic is obtained by structuring the diode to produce a non-uniform gain profile across its active layer. Alternative approaches for achieving the non-uniform gain profile include varying the thickness of the active layer, and varying the current density by employing an asymmetrical channel configuration or an asymmetrical electrical contact strip.

Abstract: Disclosed is a GaA1As laser diode wherein an abrupt etch step in the waveguide layer forms a third mirror. The structure is a large optical cavity double heterostructure laser having a relatively long active cavity and a relatively short passive cavity. Output is temperature and current sensitive for single mode operation, widely-spaced dual mode operation, and narrow-band multimode operation.

Abstract: A low loss optical waveguide is provided by taking a silicon substrate with a silicon dioxide waveguide thereon and depositing lead on the air interface surface of the silicon dioxide. The lead is then oxidized and diffused into the silicon dioxide creating a high optical quality, high index region at the air interface of the waveguide. This allows transmitted waveguide light energy directed into the silicon dioxide to be transmitted in the lead oxide diffused portion of the waveguide, keeping the energy away from the lossy silicon substrate, and thereby providing a low loss planar waveguide.