Abstract: Disclosed is a technique to estimate at least a portion of an attitude, such as an azimuth angle from true North, based on beam angles from a controlled reception pattern antenna (CRPA) to space vehicle locations. Other attitude information such as roll and/or pitch can also be estimated. The at least portion of the attitude can be provided with or without an additional sensor, such as a compass or magnetometer, an inertial measurement unit (IMU), or the like. An attitude estimate can be useful because oftentimes the attitude of an object can vary from its track or velocity direction.

Abstract: Disclosed is a technique that can provide one or more countermeasures against spoofers. A direction from which a spoofing attack occurs is identified. A beamformer can control an antenna pattern of a CRPA to null out signals from that direction, which can assist a GNSS receiver to avoid error induced by the spoofing attack. Further, after two or more observations, the location of the spoofer can be identified.

Abstract: Apparatus and methods determine the rotational position of a spinning object. A satellite positioning system can be used to determine the spatial position of an object, which in turn can be used to guide the object. An adaptive sideband filter is used to provide increased robustness against interference. However, when the object is spinning, such as an artillery shell, then the rotational orientation should be known in order to properly actuate the control surfaces, such as fins, which will also be spinning.

Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.

Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.

Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.

Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.

Abstract: Apparatus and methods spread input symbols for transmission in multiple dimensions. When input symbols are spread over time, frequency, and code space, the resulting symbols exhibit good immunity to interference. In one embodiment, a system with a multi-tone outer code/modulation and a direct sequence spread spectrum (DSSS) inner code/modulation provides good communications performance characteristics and can be efficiently implemented.

Abstract: Apparatus and methods determine the rotational position of a spinning object. A satellite positioning system can be used to determine the spatial position of an object, which in turn can be used to guide the object. However, when the object is spinning, such as an artillery shell, then the rotational orientation should be known in order to properly actuate the control surfaces, such as fins, which will also be spinning.

Abstract: Apparatus and methods determine the rotational position of a spinning object. A satellite positioning system can be used to determine the spatial position of an object, which in turn can be used to guide the object. However, when the object is spinning, such as an artillery shell, then the rotational orientation should be known in order to properly actuate the control surfaces, such as fins, which will also be spinning.

Abstract: Apparatus and methods provide a guidance kit that can be attached to a projectile, such as screwed into a fuze well of an artillery round or a mortar round. A portion of the guidance kit is configured to spin constantly during flight. In the context of an artillery round that is shot from a rifled barrel, the direction of the spin torque is counter to the direction of the spin induced by the rifled barrel. Control surfaces are present in the portion of the guidance kit that spins constantly during flight. While the portion spins, the control surfaces are actuated to steer the projectile towards an intended target via, for example, GPS.

Abstract: A general-purpose Analog Signal Processing System (ASPS) is disclosed. An ASPS can be realized though an array of Configurable Integrator Blocks (CIBs). The CIBs can be identical to each other, and arranged in rows and columns. A CIB can merge multiplication, integration, and sample-and-hold functions into a single programmable circuit block. Within the ASPS, CIBs are interconnected in a manner that allows CIB inputs to be a combination of external signals and outputs of other CIBs, and allows CIB outputs to be combined to produce system (external) outputs or inputs to other CIBs. This networked architecture combined with the basic functionality of each CIB, enables implementation of a broad range of analog signal processing operations. The ASPS can be field programmable. The field programmability permits end users to be able to quickly and inexpensively fabricate customized analog integrated circuits.

Abstract: Apparatus and methods provide a kit for converting a conventional mortar round into a glide bomb. Mortar rounds are readily available to combat personnel and are small and light enough to be carried by relatively small unmanned aerial vehicles (UAVs) such as the RQ-7 Shadow. Advantageously, the kit provides both guidance and relatively good standoff range for the UAV such that the kit-equipped mortar round can be dropped a safe distance away from the intended target so that the UAV is not easily observed near the intended target.

Abstract: Apparatus and methods determine the rotational position of a spinning object. A satellite positioning system can be used to determine the spatial position of an object, which in turn can be used to guide the object. However, when the object is spinning, such as an artillery shell, then the rotational orientation should be known in order to properly actuate the control surfaces, such as fins, which will also be spinning.

Abstract: Apparatus and methods determine the rotational position of a spinning object. A satellite positioning system can be used to determine the spatial position of an object, which in turn can be used to guide the object. However, when the object is spinning, such as an artillery shell, then the rotational orientation should be known in order to properly actuate the control surfaces, such as fins, which will also be spinning.

Abstract: A receiver despreads a spread spectrum sequence by partially despreading the spread spectrum sequence using an outer spreading code, and then despreading the partially despread sequence using an inner spreading code. This can advantageously save processing power. In one embodiment, the outer spreading code is despread with an analog circuit, and an inner spreading code is despread with a digital circuit. A modulator for a transmitter can generate a spread spectrum sequence by direct-sequence spreading data to generate a partially spread sequence and then spreading the partially spread sequence to generate the spread spectrum sequence.

Abstract: An apparatus and method allow receivers to quickly acquire a pseudorandom noise signal. A receiver advantageously detects frequency shifts using a compact parallel process hardware implementation of a Discrete Fourier Transform (DFT). The simultaneous detection of multiple frequencies allows the receiver to search the frequency range of the transmitted signal in larger increments of frequency, thereby increasing the speed of acquisition. One receiver does not use coherent integration before computation of the transform and advantageously maintains a flat frequency response. The flat frequency response of the DFT circuit enables searching of multiple frequency offsets without CPU intensive processing to compensate for frequency response variations. A receiver can include a Doppler correction circuit, which permits correlation data with frequency shift in the code to be non-coherently integrated among relatively fewer addresses or tap positions in memory.

Abstract: An apparatus and method allow receivers to quickly acquire a pseudorandom noise signal. A receiver advantageously detects frequency shifts using a compact parallel process hardware implementation of a Discrete Fourier Transform (DFT). The simultaneous detection of multiple frequencies allows the receiver to search the frequency range of the transmitted signal in larger increments of frequency, thereby increasing the speed of acquisition. One receiver does not use coherent integration before computation of the transform and advantageously maintains a flat frequency response. The flat frequency response of the DFT circuit enables searching of multiple frequency offsets without CPU intensive processing to compensate for frequency response variations. A receiver can include a Doppler correction circuit, which permits correlation data with frequency shift in the code to be non-coherently integrated among relatively fewer addresses or tap positions in memory.

Abstract: A system for efficiently filtering interfering signals in a front end of a GPS receiver is disclosed. Such interfering signals can emanate from friendly, as well as unfriendly, sources. One embodiment includes a GPS receiver with a space-time adaptive processing (STAP) filter. At least a portion of the interfering signals are removed by applying weights to the inputs. One embodiment adaptively calculates and applies the weights by Fourier Transform convolution and Fourier Transform correlation. The Fourier Transform can be computed via a Fast Fourier Transform (FFT). This approach advantageously reduces computational complexity to practical levels. Another embodiment utilizes redundancy in the covariance matrix to further reduce computational complexity. In another embodiment, an improved FFT and an improved Inverse FFT further reduce computational complexity and improve speed.

Abstract: An apparatus and method allow receivers to quickly acquire a pseudorandom noise signal. A receiver advantageously detects frequency shifts using a compact parallel process hardware implementation of a Discrete Fourier Transform (DFT). The simultaneous detection of multiple frequencies allows the receiver to search the frequency range of the transmitted signal in larger increments of frequency, thereby increasing the speed of acquisition. One receiver does not use coherent integration before computation of the transform and advantageously maintains a flat frequency response. The flat frequency response of the DFT circuit enables searching of multiple frequency offsets without CPU intensive processing to compensate for frequency response variations. A receiver can include a Doppler correction circuit, which permits correlation data with frequency shift in the code to be non-coherently integrated among relatively fewer addresses or tap positions in memory.