Abstract: An apparatus and digital signal processing means are disclosed for excision of co-channel interference from signals received in crowded or hostile environments using spatial/polarization diverse arrays, which reliably and rapidly identifies communication signals with transmitted features that are self-coherent over known framing intervals due to known attributes of the communication network, and exploits those features to develop diversity combining weights that substantively excise that co-channel interference from those communication signals, based on differing diversity signature, timing offset, and carrier offset between the network signals and the co-channel interferers. In one embodiment, the co-channel interference excision is performed in an appliqué that can be implemented without coordination with a network transceiver.

Abstract: An adaptive processor implements partial updates when it adjusts weights to optimize adaptation criteria in signal estimation, parameter estimation, or data dimensionality reduction algorithms. The adaptive processor designates some of the weights to be update weights and the other weights to be held weights. Unconstrained updates are performed on the update weights, whereas updates to the set of held weights are performed within a reduced-dimensionality subspace. Updates to the held weights and the update weights employ adapt-path operations for tuning the adaptive processor to process signal data during or after tuning.

Abstract: A method and apparatus detects and estimates geo-observables of navigation signals employing civil formats with repeating baseband signal components, i.e., “pilot signals,” including true GNSS signals generated by satellite vehicles (SV’s) or ground beacons (pseudolites), and malicious GNSS signals, e.g., spoofers and repeaters. Multi-subband symbol-rate synchronous channelization can exploit the full substantive bandwidth of the GNSS signals with managed complexity in each subband. Spatial/polarization receivers can be provided to remove interference and geolocate non-GNSS jamming sources, as well as targeted GNSS spoofers that emulate GNSS signals.

Abstract: An adaptive processor implements partial updates when it adjusts weights to optimize adaptation criteria in signal estimation, parameter estimation, or data dimensionality reduction algorithms. The adaptive processor designates some of the weights to be update weights and the other weights to be held weights. Unconstrained updates are performed on the update weights, whereas updates to the set of held weights are performed within a reduced-dimensionality subspace. Updates to the held weights and the update weights employ adapt-path operations for tuning the adaptive processor to process signal data during or after tuning.

Abstract: A method and apparatus detects and estimates geo-observables of navigation signals employing civil formats with repeating baseband signal components, i.e., “pilot signals,” including true GNSS signals generated by satellite vehicles (SV's) or ground beacons (pseudolites), and malicious GNSS signals, e.g., spoofers and repeaters. Multi-subband symbol-rate synchronous channelization can exploit the full substantive bandwidth of the GNSS signals with managed complexity in each subband. Spatial/polarization receivers can be provided to remove interference and geolocate non-GNSS jamming sources, as well as targeted GNSS spoofers that emulate GNSS signals. This can provide time-to-first-fix (TTFF) over much smaller time intervals than existing GNSS methods; can operate in the presence of signals with much wider disparity in received power than existing techniques; and can operate in the presence of arbitrary multipath.

Abstract: An apparatus and digital signal processing means are disclosed for excision of co-channel interference from signals received in crowded or hostile environments using spatial/polarization diverse arrays, which reliably and rapidly identifies communication signals with transmitted features that are self-coherent over known framing intervals due to known attributes of the communication network, and exploits those features to develop diversity combining weights that substantively excise that co-channel interference from those communication signals, based on differing diversity signature, timing offset, and carrier offset between the network signals and the co-channel interferers. In one embodiment, the co-channel interference excision is performed in an appliqué that can be implemented without coordination with a network transceiver.

Abstract: Co-channel beacon transmissions are provided with at least one of spectral redundancy and temporal redundancy. A receiver produces a snapshot of a superposition of received co-channel beacon transmissions. Subcarrier demodulation, code nulling, or a Class-C linear minimum-mean-square error (MMSE) operation separates multiples ones of the co-channel beacon transmissions or eliminates inter-symbol interference and inter-subcarrier interference in the snapshot. Receiver operations can be performed at a network user, a network node, or a network operations center.

Abstract: An apparatus and digital signal processing means are disclosed to reliably and rapidly receive and detect navigation signals, e.g., Global Navigation Satellite System (GNSS) signals, such as Global Position System (GPS) L1 legacy, L1C, and L5 signals, using combinations of spatially diverse antenna arrays, polarization-diverse antenna arrays, frequency-channelized analysis filters, and perfect-reconstruction synthesis filters, by exploiting features of those signals that are self-coherent over known framing intervals. Among other advantages, the means can reliably and rapidly identify navigation signals based on those features, improve their quality ahead of, or during, signal despreading operations, and detect and excise inadvertent or targeted electronic attack (EA) measures, e.g., navigation signal spoofers, and narrowband or wideband jamming and co-channel interference.

Abstract: A method and apparatus for reception of signals with unpredictable transmission properties enabling physically secure, unscheduled and interference-resistant communication over machine-to-machine (M2M) networks is claimed. A physical structure employs combinations of unpredictable physical dwells, spreading vectors, and selection of intended receivers. Reception methods employ blind detection and signal separation techniques, which can detect and extract transmissions intended for a receiver, and excise transmissions not intended for that receiver, as part of the despreading procedure, even if received at much higher power levels than the intended transmissions.

Abstract: A method and apparatus detects and estimates geo-observables of navigation signals employing civil formats with repeating baseband signal components, i.e., “pilot signals,” including true GNSS signals generated by satellite vehicles (SV's) or ground beacons (pseudolites), and malicious GNSS signals, e.g., spoofers and repeaters. Multi-subband symbol-rate synchronous channelization can exploit the full substantive bandwidth of the GNSS signals with managed complexity in each subband. Spatial/polarization receivers can be provided to remove interference and geolocate non-GNSS jamming sources, as well as targeted GNSS spoofers that emulate GNSS signals. This can provide time-to-first-fix (TTFF) over much smaller time intervals than existing GNSS methods; can operate in the presence of signals with much wider disparity in received power than existing techniques; and can operate in the presence of arbitrary multipath.

Abstract: A method and apparatus is claimed here for reduced-complexity detection and estimation of geo-observables of global navigation satellite systems (GNSS) signals employing civil formats with repeating ranging codes, including true GNSS signals generated by satellite vehicles (SV's) or ground beacons (pseudo-lites), and malicious GNSS signals, e.g., spoofers and repeaters, using multi-subband symbol-rate synchronous channelization architectures that can exploit the full substantive bandwidth of the GNSS signals with managed complexity in each subband. Aspects employing spatial/polarization receivers are also claimed that can remove and geolocate non-GNSS jammers received by the system, as well as targeted GNSS spoofers that can otherwise emulate GNSS signals received at victim receivers.

Abstract: An apparatus and digital signal processing means are disclosed to reliably and rapidly receive and detect navigation signals, e.g., Global Navigation Satellite System (GNSS) signals, such as Global Position System (GPS) L1 legacy, L1C, and L5 signals, using combinations of spatially diverse antenna arrays, polarization-diverse antenna arrays, frequency-channelized analysis filters, and perfect-reconstruction synthesis filters, by exploiting features of those signals that are self-coherent over known framing intervals. Among other advantages, the means can reliably and rapidly identify navigation signals based on those features, improve their quality ahead of, or during, signal despreading operations, and detect and excise inadvertent or targeted electronic attack (EA) measures, e.g., navigation signal spoofers, and narrowband or wideband jamming and co-channel interference.

Abstract: A method and apparatus for reception of signals with unpredictable transmission properties enabling physically secure, unscheduled and interference-resistant communication over machine-to-machine (M2M) networks is claimed. A physical structure comprising combinations of unpredictable physical dwells, spreading vectors, and selection of intended receivers is described. Reception methods employing blind detection and signal separation techniques are then described, which can detect and extract transmissions intended for a receiver, and excise transmissions not intended for that receiver, as part of the despreading procedure, even if received at much higher power levels than the intended transmissions.

Abstract: An adaptive processor implements partial updates when it adjusts weights to optimize adaptation criteria in signal estimation, parameter estimation, or data dimensionality reduction algorithms. The adaptive processor designates some of the weights to be update weights and the other weights to be held weights. Unconstrained updates are performed on the update weights, whereas updates to the set of held weights are performed within a reduced-dimensionality subspace. Updates to the held weights and the update weights employ adapt-path operations for tuning the adaptive processor to process signal data during or after tuning.

Abstract: A receiver processes Global Navigation Satellite System (GNSS) signals transmitted from satellites and non-satellite signals transmitted from beacons. The receiver comprises an adaptive despreader configured for adaptively despreading a channelizer output signal-to extract received navigation signals and generate baseband symbol data therefrom. The channelizer output signal comprises channelized received navigation signals, each comprising a spreading code that repeats every baseband symbol. A copy-aided analyzer is communicatively coupled to the adaptive despreader and configured for determining geo-observables from the baseband symbol data of at least one received navigation signal.

Abstract: A receiver processes Global Navigation Satellite System (GNSS) signals transmitted from satellites and non-satellite signals transmitted from beacons. The receiver comprises a symbol-rate synchronous vector channelizer configured to downconvert and channelize a plurality of received navigation signals to produce a vector signal with a sample rate equal to a baseband symbol rate of at least one navigation signal, less any offset due to Analog-to-Digital Converter clock error. A despreader is communicatively coupled to the channelizer and configured to exploit properties of baseband symbol data in the navigation signal to blindly despread the vector signal and extract the plurality of received navigation signals.

Abstract: Signals with unpredictable transmission properties enabling physically secure, unscheduled and interference-resistant machine-to-machine (M2M) communication are described. A physical dwell structure containing time slots and frequency channels is established, and a combination of unpredictable physical dwells, spread spectrum modulation with unpredictable spreading vectors, and unpredictable selection of intended receivers is described. These unpredictable transmission properties enable receivers to detect and extract transmissions intended for the receiver, and excise transmissions not intended for the receiver, even if they are received at much higher power levels than the intended transmissions.

Abstract: An apparatus and digital signal processing means are disclosed for excision of co-channel interference from signals received in crowded or hostile environments using spatial/polarization diverse arrays, which reliably and rapidly identifies communication signals with transmitted features that are self-coherent over known framing intervals due to known attributes of the communication network, and exploits those features to develop diversity combining weights that substantively excise that co-channel interference from those communication signals, based on differing diversity signature, timing offset, and carrier offset between the network signals and the co-channel interferes. In one embodiment, the co-channel interference excision is performed in an appliqué that can be implemented without coordination with a network transceiver.

Abstract: A method is explained for any adaptive processor processing digital signals by adjusting signal weights on digital signal(s) it handles, to optimize adaptation criteria responsive to a functional purpose or externalities (transient, temporary, situational, and even permanent) of that processor. Adaptation criteria for the adaptive algorithm may be any combination of a signal or parameter estimation, and measured quality(ies). This method performs a linear transformation adapting parameters from M to (M1+L) dimensions in each adaptation event, such that M1 weights are updated without constraints and M0=M?M1 weights are forced by soft constraints into an L-dimensional subspace they spanned at the beginning of the adaptation period. The same dimensionality reduction, using the same linear transformation, is applied to the input data.

Abstract: A receiver processes Global Navigation Satellite System (GNSS) signals transmitted from satellites and non-satellite signals transmitted from beacons. The receiver comprises an adaptive despreader configured for adaptively despreading a channelizer output signal-to extract received navigation signals and generate baseband symbol data therefrom. The channelizer output signal comprises channelized received navigation signals, each comprising a spreading code that repeats every baseband symbol. A copy-aided analyzer is communicatively coupled to the adaptive despreader and configured for determining geo-observables from the baseband symbol data of at least one received navigation signal.