Abstract: A digital engineering (DE) platform configured to support space system development and acquisition. The DE platform includes a modular reference architecture models module configured to capture key modular system elements of interest using model-based system engineering (MBSE) and digital object oriented requirements system (DOORS) tools. The DE platform also includes a connectivity matrix module defining interface or specifications between one or more modular system elements. The DE platform is also configured to digitize the interface using a behavior model. The behavior model capturing required activity and/or sequence for a particular use case.

Abstract: A system for hybrid modulation and demodulation includes a transmitter and a receiver. The transmitter is configured to receive a hybrid signal of a space-ground link system (SGLS), including a first component and a second component; perform a double sideband (DSB) modulation on the first component using a carrier frequency to obtain a first waveform; perform a single sideband (SSB) modulation on the second component using the carrier frequency to obtain a second waveform; mix the first waveform and the second waveform to generate a hybrid waveform; and transmit the hybrid waveform. The receiver is configured to receive the hybrid waveform; determine the carrier frequency; separate the first waveform and the second waveform; perform a DSB demodulation on the first waveform to obtain a first demodulated signal; and perform an SSB demodulation on the second waveform to obtain a second demodulated signal.

Abstract: A digital engineering (DE) platform configured to support space system development and acquisition. The DE platform includes a modular reference architecture models module configured to capture key modular system elements of interest using model-based system engineering (MBSE) and digital object oriented requirements system (DOORS) tools. The DE platform also includes a connectivity matrix module defining interface or specifications between one or more modular system elements. The DE platform is also configured to digitize the interface using a behavior model. The behavior model capturing required activity and/or sequence for a particular use case.

Abstract: A system for hybrid modulation and demodulation includes a transmitter and a receiver. The transmitter is configured to receive a hybrid signal of a space-ground link system (SGLS), including a first component and a second component; perform a double sideband (DSB) modulation on the first component using a carrier frequency to obtain a first waveform; perform a single sideband (SSB) modulation on the second component using the carrier frequency to obtain a second waveform; mix the first waveform and the second waveform to generate a hybrid waveform; and transmit the hybrid waveform. The receiver is configured to receive the hybrid waveform; determine the carrier frequency; separate the first waveform and the second waveform; perform a DSB demodulation on the first waveform to obtain a first demodulated signal; and perform an SSB demodulation on the second waveform to obtain a second demodulated signal.

Abstract: A systematic interferences mitigation design for protected satellite communications (SATCOM) is provided. An advanced channel coding is designed to provide coding gain for SATCOM even in the presence of synchronization errors because of unintentional and intentional radio frequency interferences (RFIs). A unified SATCOM system spectrum efficiency and energy efficiency performance model is developed with a unified interference model for SATCOM dynamic resource allocation (DRA). The SATCOM system DRA is designed with a game theoretic engine and link optimizations providing traffic control, power control, frequency hopping pattern selection, beamforming codebook selection, and modulation with coding agile waveform adaptations. The interferences mitigation design is implemented with software defined radio USRP and GNU-radio to maintain communication link quality of services (QoS).

Abstract: A systematic interferences mitigation design for protected satellite communications (SATCOM) is provided. An advanced channel coding is designed to provide coding gain for SATCOM even in the presence of synchronization errors due to the effect of radio frequency interferences (RFIs). A unified SATCOM system spectrum efficiency and energy efficiency method is developed with a unified interference model for SATCOM dynamic resource allocation (DRA). The SATCOM system DRA is designed with a game theoretic engine and optimizations providing traffic control, power control, and modulation and coding agile waveform adaptations. The interferences mitigation design is implemented with software defined radio USRP and GNU-radio to maintain communication link quality of services (QoS).

Abstract: An apparatus interfaces a commercial-off-the-shelf (COTS)/off-the-shelf (OTS) modem for pulsed data communication using existing sensor aperture among radar platforms. The apparatus includes a demodulator for receiving a sequence of first pulse signals, at least one first pulse signal of the sequence of first pulse signals being modulated with an input signal. The demodulator includes a pulse regeneration module for regenerating a pulse timing of the sequence of first pulse signals and a pulse demodulation module for demodulating the sequence of first pulse signals to recover the input signal in synchronization with the pulse timing of the sequence of first pulse signals.

Abstract: Systems and methods for detecting and tracking a gun using millimeter waves are provided. In one embodiment, the invention relates to a method for detecting and tracking a gun using radio frequency waves at millimeter wavelengths, the method including storing empirical data, for up to N types of guns, including information indicative of a resonant frequency of a barrel of each of the N guns, generating pulse energy including at least one sequence of pulses at millimeter wave frequencies for each of the N guns, transmitting the pulse energy, receiving reflected pulse energy, filtering the reflected pulse energy to a preselected bandwidth for each of the N guns, determining a first maximum value of the filtered reflected pulse energy in each of the preselected bandwidths that exceeds a preselected threshold, determining a second maximum value among the first maximum values, and correlating a frequency of the second maximum value with the stored resonant frequencies of the N guns to identify a gun.

Abstract: Systems and methods for detecting and tracking a gun using millimeter waves are provided. In one embodiment, the invention relates to a method for detecting and tracking a gun using radio frequency waves at millimeter wavelengths, the method including storing empirical data, for up to N types of guns, including information indicative of a resonant frequency of a barrel of each of the N guns, generating pulse energy including at least one sequence of pulses at millimeter wave frequencies for each of the N guns, transmitting the pulse energy, receiving reflected pulse energy, filtering the reflected pulse energy to a preselected bandwidth for each of the N guns, determining a first maximum value of the filtered reflected pulse energy in each of the preselected bandwidths that exceeds a preselected threshold, determining a second maximum value among the first maximum values, and correlating a frequency of the second maximum value with the stored resonant frequencies of the N guns to identify a gun.

Abstract: An apparatus interfaces a commercial-off-the-shelf (COTS)/off-the-shelf (OTS) modem for pulsed data communication using existing sensor aperture among radar platforms. The apparatus includes a demodulator for receiving a sequence of first pulse signals, at least one first pulse signal of the sequence of first pulse signals being modulated with an input signal. The demodulator includes a pulse regeneration module for regenerating a pulse timing of the sequence of first pulse signals and a pulse demodulation module for demodulating the sequence of first pulse signals to recover the input signal in synchronization with the pulse timing of the sequence of first pulse signals.

Abstract: A timing recovery loop includes a random walk filter counter for counting early, nominal and late arrivals of data transitions pulses of an input baseband signal waveform encoding a digital bit stream, and provides magnitude counts that are compared to a threshold value that when exceeded by the magnitude counts results in a delay adjustment of the generated adjusted timing pulses then remaining synchronized with the actual bit timing for maintaining bit timing lock. The adjusted timing pulses can then be used by a data detector for reliable data detection and reconstruction of the digital bit stream. The threshold value can be adaptively adjusted for reducing drop lock rates in the presence of changing channel environments.

Abstract: The present invention features multiple ideas that enable building and maintaining process scorecard models for a large number of process variations; process reference scorecard models and process/IT scorecard delta models. Specifically, the present invention provides a solution for managing a process and IT interlock. Under this solution a tabular model of a process having process steps along a first axis and process variations along a second axis, with cells at the intersections of the axes is constructed. Process step details including IT details for a base process are populated into the cells of a first row of the second axis. Delta details (to-be base cases) of the process steps for each of the process variations are populated into additional rows of the second axis. Project management status indicators are enabled for each cell to denote statuses of the process steps in each cell.

Abstract: A polyphase channelizer converts an intermediate frequency wideband signal into a complex signal that is sampled by parallel analog-to-digital converters having a bank of samplers respectively clocked by staggered clocking signals for respective converters for feeding I and Q quadrature samples to a polyphase filter bank of finite impulse response filters driving a fast Fourier transform processor for providing channelized digital signal outputs. The parallel analog-to-digital converters can operate at lower speeds but are parallel connected for effectively operating at required higher speeds. The channelizer channelizes the wideband signal using a polyphase clock for enabling high speed sampling and converting through low speed parallel analog to digital converters.

Abstract: A coherent adaptive subcarrier modulation system applies subcarrier modulation to quadrature modulated signals with constant envelope modulation suitable for efficient sinewave and squarewave subcarrier modulations. The quadrature subcarrier enables the addition of new signals to the in-phase and quadrature phase signals with spectral isolation in the Global Position System while maintaining a constant envelop amplitude.

Abstract: A command and telemetry communication system includes a downlink subsystem having a spacecraft downlink transmitter communicating a quadrature component carrying a pilot code for coarse acquisition and an inphase component carrying a Walsh-Hadamard code and a PN code for fine acquisition using spread spectrum signaling and amplitude modulation for code division multiplexing to downlink receivers respectively disposed in a plurality of mobile surface landers, and includes an uplink subsystem having a spacecraft uplink receiver and lander uplink transmitters communicating code division multiple access telemetry data using spread spectrum signaling and phase modulation. The communication system enables command and telemetry control of a plurality of mobile surface landers.

Abstract: An adaptive predistorter system receives and predistorts an input signal so as to linearize the output signal of a nonlinear high power amplifier amplifying the predistorted input signal using closed-loop feedback of the output signal in complex form at baseband so as to adaptively change the amount of the predistortion of the input signal in the presence of high power amplifier changing characteristics.

Abstract: A command and telemetry communication system includes a downlink subsystem having a spacecraft downlink transmitter communicating a quadrature component carrying a pilot code for coarse acquisition and an inphase component carrying a Walsh-Hadamard code and a PN code for fine acquisition using spread spectrum signaling and amplitude modulation for code division multiplexing to downlink receivers respectively disposed in a plurality of mobile surface landers, and includes an uplink subsystem having a spacecraft uplink receiver and lander uplink transmitters communicating code division multiple access telemetry data using spread spectrum signaling and phase modulation. The communication system enables command and telemetry control of a plurality of mobile surface landers.

Abstract: An adaptive predistorter system receives and predistorts an input signal so as to linearize the output signal of a nonlinear high power amplifier amplifying the predistorted input signal using closed-loop feedback of the output signal in complex form at baseband so as to adaptively change the amount of the predistortion of the input signal in the presence of high power amplifier changing characteristics.

Abstract: A timing recovery loop includes a random walk filter counter for counting early, nominal and late arrivals of data transitions pulses of an input baseband signal waveform encoding a digital bit stream, and provides magnitude counts that are compared to a threshold value that when exceeded by the magnitude counts results in a delay adjustment of the generated adjusted timing pulses then remaining synchronized with the actual bit timing for maintaining bit timing lock. The adjusted timing pulses can then be used by a data detector for reliable data detection and reconstruction of the digital bit stream. The threshold value can be adaptively adjusted for reducing drop lock rates in the presence of changing channel environments.

Abstract: A polyphase channelizer converts an intermediate frequency wideband signal into a complex signal that is sampled by parallel analog-to-digital converters having a bank of samplers respectively clocked by staggered clocking signals for respective converters for feeding I and Q quadrature samples to a polyphase filter bank of finite impulse response filters driving a fast Fourier transform processor for providing channelized digital signal outputs. The parallel analog-to-digital converters can operate at lower speeds but are parallel connected for effectively operating at required higher speeds. The channelizer channelizes the wideband signal using a polyphase clock for enabling high speed sampling and converting through low speed parallel analog to digital converters.