Abstract: System and method for concurrent STAP (space-time adaptive processing) filtering of interference signals (e.g., jamming signals) from signals received at a broadband antenna array via satellite and terrestrial broadcasts and communication systems operating in the 950 MHz to 1.65 GHz L-band, including but not limited to Link 16 terrestrial communications, Iridium satellite communications, and the Global Positioning System (GPS) and other Global Navigation Satellite Systems (GNSS). While the GPS/GNSS signals are protected against jamming using Nulling of the interfering signals, the Iridium and other communication systems' signals are protected using Beamforming. Use of a common broadband antenna and common front-end signal processing of the received signals enables an integrated system for use on a wide range of platforms, including without limitation size-, weight-, and power-constrained platforms such as drones, unmanned aerial vehicles (UAVs), and helicopters.

Abstract: System and method for concurrently protecting Iridium and GPS L1/L2 band received satellite signals against interference signals (e.g., jamming signals) using space-time adaptive processing (STAP). While the GPS signal is protected against jamming using Nulling of the interfering signals, the Iridium signal is protected using Beamforming. A single broadband small controlled reception pattern antenna (sCRPA) array receives both the GPS (L1 and L2) and Iridium signals for the STAP-based antijam solutions outputting filtered Iridium and GPS signals. Use of a common (small) broadband antenna and common front end signal processing of the received signals enables an integrated system for use on size, weight, and power constrained platforms such as drones, unmanned aerial vehicles (UAVs), and helicopters.

Abstract: System and method for concurrently protecting Iridium and GPS L1/L2 band received satellite signals against interference signals (e.g., jamming signals) using space-time adaptive processing (STAP). While the GPS signal is protected against jamming using Nulling of the interfering signals, the Iridium signal is protected using Beamforming. A single broadband small controlled reception pattern antenna (sCRP) array receives both the GPS (L1 and L2) and Iridium signals for the STAP-based antijam solutions outputting filtered Iridium and GPS signals. Use of a common (small) broadband antenna and common front end signal processing of the received signals enables an integrated system for use on size, weight, and power constrained platforms such as drones, unmanned aerial vehicles (UAVs), and helicopters.

Abstract: System and method for mean phase compensation of code and carrier phase distortions induced by Space Time Adaptive Processing (STAP) filters used for removing interferences from received GPS signals. The phase distortion is mitigated (without the use of beamforming) using a single STAP filter for processing the GPS satellite channels in which appropriate bundling of constraints is applied to the filter weights. The complete solution can be contained in the antenna electronics with no required changes to the legacy GPS receiver.

Abstract: System and method for determining the roll rate and roll angle of a spinning platform. The IQ amplitude and/or phase characteristics of GPS signals received at a single receiver antenna are measured using the signals output directly by a correlator that is driven at the satellite tracking frequency used for forming the navigation solution. The roll rate and roll angle are determined in real time by a Roll filter, which is preferably an Extended Kalman Filter (EKF) employing probabilistic data association, whose inputs include the measured IQ characteristics and the navigation solution. Data from non-GPS measurement sources is optionally provided to update the navigation and/or roll solution.

Abstract: System and method for mean phase compensation of code and carrier phase distortions induced by Space Time Adaptive Processing (STAP) filters used for removing interferences from received GPS signals. The phase distortion is mitigated (without the use of beamforming) using a single STAP filter for processing the GPS satellite channels in which appropriate bundling of constraints is applied to the filter weights. The complete solution can be contained in the antenna electronics with no required changes to the legacy GPS receiver.

Abstract: System and method for providing data transport Quality of Service (QoS) assurances in homogeneous and heterogeneous communication networks consisting of one or more communication interface types. The system includes Subnet Managers for managing the resources of nodes within the subnets and Flow Managers for managing the communication flows between the nodes. A Real-time Reservation Transport Protocol (RRTP) establishes the resource reservations and QoS transport services for the communication flow payload over the reserved paths. The communication flows are protected against topological variations in the network, such as from node mobility. QoS assurances are also provided to secure communication flows through interoperation with security protocols, such as Internet Protocol Security (IPsec), or encryption devices, such as High Assurance Internet Protocol Encryptor (HAIPE).

Abstract: System and method for topology management of dynamic ad hoc wireless communication networks. The network nodes are organized in a multi-level hierarchical architecture whereby the nodes at each level are managed by nodes at the next higher level. In a three-layer network, leaf nodes populate the lowest level, cluster head nodes the intermediate level, and regional head nodes the highest level. Priority-based backbone tree paths are constructed by selecting and connecting high capability nodes, such that the unselected nodes are one-hop away from a connected node. In a two backbone tree path construction, a primary backbone tree path carries the high priority traffic and a secondary backbone tree path carries the lower priority traffic. The connectivities of the backbone tree paths are maintained dynamically. So also are high priority traffic flows using the Dynamic Priority Threshold mechanism with High Fidelity Monitoring and traffic siphoning via unutilized network resources.

Abstract: A system and method for determining the roll rate and roll angle of a spinning platform by using the measured phase and/or amplitude differences between the GPS satellite signals received on two or more antennas. The measured signal differences and the navigation solution from a GPS receiver are processed in a roll filter to obtain the desired information. Data from non-GPS measurement sources is optionally provided to update the navigation solution. Although of wide applicability, the invention is uniquely suited to the measurement of roll rates and roll angles of fast spinning platforms with small baselines in the presence as well as in the absence of jamming, and where the antennas are separated from each other by distances that are a fraction of the GPS signal wavelength.

Abstract: A system and method for determining the roll rate and roll angle of a spinning platform in a jamming environment, by suppressing the interference signals from the received GPS signals and using the measured phase and amplitude differences between the GPS satellite signals received on two or more antennas. The measured signal differences and the navigation solution from a GPS receiver are processed in a roll filter to obtain the desired information. Data from non-GPS measurement sources is optionally provided to update the navigation solution. Although of wide applicability, the invention is uniquely suited to the measurement of roll rates and roll angles of fast spinning platforms with small baselines in the presence of jamming, and where the antennas are separated from each other by distances that are a fraction of the GPS signal wavelength.

Abstract: A multimode Radio Access Network (RAN) for wireless communication is disclosed. The RAN separates the control signals from the data streams for their distributed processing. The control signals are transmitted between base stations and a Radio Resource Server (RRS), while the data streams are communicated between the base stations and Wireless Access Gateways (WAGs). The base station and WAG resources are managed by the RRS. Besides providing single and multiple radio mode access to a mobile user for efficient communication with other wireless communication networks, the RAN infrastructure has a high outage tolerance and can be scaled cost effectively for wider coverage and increased data traffic capacity.

Abstract: A system and method for determining the roll rate and roll angle of a spinning platform, using the measured phase differences between the GPS satellite signals received on two or more antennas. The measured phase differences and the navigation solution from a GPS receiver are processed in a Kalman filter to obtain the desired information. Data from non-GPS measurement sources is optionally provided to update the navigation solution. Although of wide applicability, the invention is uniquely suited to the measurement of roll rates and roll angles of fast spinning platforms with small baselines, in which the antennas are separated from each other by distances that are a fraction of the GPS signal wavelength.

Abstract: An antijam filter and method for filtering interference signals from signals received from the desired user in spatially multiplexed wireless communication systems. The antijam filter estimates the interference from known and unknown sources, and uses that estimate to filter the interference from the received signals. The filtered desired user signals are rendered for further signal processing using existing methods. The antijam filter and method are modular, with applicability to a wide range of wireless communication systems employing multiple antennas at the receiver.

Abstract: A spread spectrum interference canceller includes a downconverter for amplifying and translating the received signal from the radio frequency band to baseband, said signal comprising multiple direct sequence-spread spectrum signals and multiple narrowband interferers; a digital adaptive transversal filter for processing the downconverter output signal to suppress the narrowband interferers, and for regulating the amplitude of the resulting signal; an upconverter for translating the filter output from baseband to the radio frequency band, so that the resulting interference canceller output can be processed by a spread spectrum receiver.

Abstract: A digital adaptive transversal filter includes an interface circuit for regulating and digitizing analog input signals, which comprise of multiple spread-spectrum signals, additive thermal noise and additive multiple narrowband interferers, to provide multi-bit digital input signals. A digital finite impulse response filter having a set of variable digital weight coefficients responds to the multi-bit digital input signals to generate digital output signals which contain a reduced amount of narrowband interference. A digital weight generator responds to the digital input and digital output signals for updating the digital weight coefficients, and a reset generator periodically resets the digital weight coefficients to zero initial values.In a preferred embodiment an 8-tap, 8-bit digital adaptive transversal filter operating at 22 MHz was implemented with discrete components and a processing gain of 30 dB was demonstrated.