Abstract: Embodiments of the invention monitor requests for a source code build of a program. The source code build is generated using the most recent applicable release of the dependencies. The source code build is dynamically merged into at least one subsequent release. Other embodiments may be described and claimed.

Abstract: An apparatus for sensing and classifying radio communications is provided. The apparatus includes one or more sensor units configured to detect radio frequency signals, a signal classifier configured to classify the detected radio frequency signals into a classification, the classification including at least one known signal type and an unknown signal type, a clustering learning algorithm capable of finding clusters of common signals among the previously seen unknown signals. The system is then further configured to use these clusters to retrain the signal classifier to recognize these signals as a new signal type.

Abstract: Methods and systems for signal quantization may include, but are not limited to: receiving a complex signal characterized by a real portion and an imaginary portion; computing a vector magnitude of a sample of the complex signal; comparing the vector magnitude of the sample to a quantization threshold value; and associating a quantized magnitude with the sample according to a comparison between the vector magnitude of the sample and the quantization threshold value.

Abstract: A apparatus configured to detect the presence of one or more unknown signals in the presence of noise and/or interference. The apparatus includes an input configured to receive an input data from a sensor, an integrator configured to integrate the power of the input data over a period of time, and a comparator configured to compare the integrated power to a threshold to determine if the input data contains at least one signal, or if the input data contains noise only. The apparatus may further include a mean estimator configured to estimate the mean of the power integrated input data over a period of time, a variance estimator configured to estimate the variance of the power integrated input data over a period of time, and a threshold calculator configured to calculate the threshold value based on the estimated mean or estimate mean and estimated variance.

Abstract: An apparatus for identifying a specific emitter in the presence of noise and/or interference is disclosed. The apparatus includes a sensor configured to sense radio frequency signal data, the signal data containing noise and signal from at least one emitter, a reference estimation unit configured to estimate a reference signal relating to the signal transmitted by one emitter, a feature estimation unit configured to generate one or more estimates of one or more feature from the reference signal and the signal transmitted by that particular emitter, and an emitter identifier configured to identify the signal transmitted by that particular emitter as belonging to a specific device using one or more feature estimates. The emitter identifier identifies the signal transmitted by that particular emitter as belonging to a specific device using Gaussian Mixture Models and the Bayesian decision engine.

Abstract: Spectral environment estimation systems and methods are provided for use with frequency hopped communications systems. A spectral sensor is configured to receive input signals from a signal aperture and to perform spectral estimations on the input signals to generate a frequency domain spectral estimate. Ordinary spectral characterization circuitry is configured to receive the frequency domain spectral estimate as an input and to produce an ordinary frequency domain spectral environment estimate based on the spectral estimate. Frequency hopping translation circuitry is configured to receive the frequency domain spectral estimate from the spectral sensor as an input and to produce a de-hopped channel domain spectral estimate based on the frequency domain spectral estimate.

Abstract: The present invention is directed to a small size and light weight small form factor user system suitable for having TTNT connectivity which consumes minimum power to operate. The small form factor user system having TTNT connectivity may be capable of interacting in a low latency real time manner with airborne networks. The small form factor user system having TTNT connectivity may have significantly reduced radio power consumption and form factor size through maintaining core capabilities of the full size TTNT terminal while relaxing other capabilities. An encapsulated message structure may be utilized to simplify communication between the TTNT small form factor user system and the full size TTNT nodes.

Abstract: A system for simultaneously transmitting and receiving signals in a frequency hopping system. The system includes a multiplexor configured to filter a plurality of frequency hopping message pulses based on a frequency associated with each pulse, a plurality of transceivers configured to receive the pulses from the multiplexor, and a modem configured for simultaneous transmission and reception whereby transmission of the pulses are isolated from potentially received pulses by selecting a specific sub-band and transceiver corresponding to the specific sub-band through which to transmit each pulse.

Abstract: A radio frequency receiver includes a receiving circuit for receiving and decoding an incoming radio frequency signal including a correlation signal. The receiver also includes a timing estimation circuit. The timing estimation circuit comprises a signal buffer receiving a plurality of correlation signal segments, and a first peak detection and Doppler estimation circuit for determining a first timing of a first segment and the associated first Doppler shift. The timing estimation circuit also comprises a memory coupled to the signal buffer, the memory receiving a plurality of segment correlation metrics, and a second peak detection and Doppler estimation circuit for determining a second timing of a second segment and the associated second Doppler shift.

Abstract: A system capable of operation with dynamic sockets includes a plurality of communications devices. Each of the plurality of communications devices includes high band channel radio resources capable of communications at 900-2800 MHz and socket radio resources capable of communications at 30-1000 MHz. The high band channel radio resources and the socket radio resources are significantly separated in frequency so that the high band channel radio resources and the socket radio resources are suitable for concurrent operation with no interference and minimal isolation, co-site problems to solve in each of the plurality of communications devices. The plurality of communications devices are connected to a unifying mesh network by the high band channel radio resources. The unifying mesh network is suitable for allowing the plurality of communications devices to communicate with one another.

Abstract: A receiver for carrier frequency estimation via symbol rate estimation in the presence of carrier frequency error for use in signal acquisition and signal demodulation of spread-spectrum chips affected by Doppler shift in an advanced tactical data link. Received LPD signals with a very low signal-to-noise ratio are input to a receiver designed to tolerate carrier frequency error caused by Doppler shift. Extremely low signal-to-noise ratio and short dwell times due to spread spectrum modulation and frequency-hopping make direct estimation of carrier frequency impractical. A method and apparatus is disclosed to use the error is symbol rate, the nominal carrier frequency, and the nominal transmitted symbol rate to estimate carrier frequency error. This enables longer coherent integration times and improves LPD receiver performance.

Abstract: A receiver for computationally efficient signal acquisition of spread-spectrum chips affected by Doppler shift in an advanced tactical data link. Received signals with a very low signal-to-noise ratio are parsed in a multi-stage signal acquisition circuit architecture, and compared to a known sequence to determine correlation over a subset of the known sequence. Chip-rate-coherent correlation is performed over an interval of time for which the effect of Doppler shift on the chip rate are negligible. A non-coherent block then integrates intermediate metrics to obtain final metrics for the entire known sequence. The parsing of the correlation into subsets and stages allows for a more computationally efficient solution to the Doppler shift chip rate error problem by reducing the number of intermediate metrics that must be computed at high speed.

Abstract: An architecture for a spread-spectrum transmitter-receiver system in an advanced tactical data link that allows the receiver to readily acquire and synchronize to a desired LPD signal. Signal acquisition is performed with a cyclic range search that uses multiple redundant known sequences mapped to a known message sequence in a highly repeated manner. By employing the invariance of the speed of light, and synchronicity between transmitter and receiver, the architecture can significantly reduce the computational complexity of the receiver. Additionally, the architecture enables ad hoc channel access, controlled latency, distance estimation, and distance-directed transmissions.

Abstract: A quadrature LINC transmission system processes a baseband input signal for transmission as a linearly amplified RF signal. An in-phase LINC element processes an in-phase baseband signal into an in-phase RF signal. A quadrature LINC element processes a quadrature baseband signal into a quadrature RF signal. An output combiner combines the in-phase RF signal with the quadrature RF signal to provide the linearly amplified RF signal. The in-phase LINC element has a constant envelope decomposition block for decomposing the in-phase baseband signal into in-phase baseband constant envelope components. Two up-converters convert the in-phase baseband constant envelope components to in-phase RF constant envelope components. Two non-linear amplifiers amplify the in-phase RF constant envelope components. A combiner combines the amplified in-phase RF constant envelope components to yield the in-phase RF signal. The quadrature LINC element is similar to the in-phase LINC element and provides the quadrature RF signal.

Abstract: A method and apparatus for signal acquisition with transmit blanking compensation compensates for collisions between a desired received signal and a transmitted signal. A blanking block blanks a received signal when the transmitted signal is transmitted and stops blanking when the transmitted signal stops to provide a received signal with blanking. A correlation block correlates the received signal with blanking with a known sequence of symbols corresponding to the desired received signal and outputs a correlation metric and a number of symbols blanked. Means for adjusting the correlation metric or a variable threshold using the number of symbols blanked are provided. A decision block compares the adjusted correlation metric to a fixed threshold or the correlation metric to the variable threshold. If the adjusted correlation metric exceeds the threshold or if the correlation metric exceeds the variable threshold, the decision block determines that the desired signal is detected.

Abstract: The present invention is a method and system for estimating interference. Packet characteristics of relevant packets within the channel at a given point in time may be processed. For example, a power level, occupied frequency and corresponding time references may be accumulated and stored for each relevant packet within the channel at a given point in time. As each packet is processed for demodulation, the channel samples, at which interference occurred, may be appropriately weighted based on the packet characteristics. Advantageously, the nature of the interfering channel traffic may be measured to properly de-weight the interference in a computationally efficient manner.

Abstract: A direct conversion quadrature receiver and method are provided according to the invention. The receiver according to one embodiment includes a primary local oscillator (LO) that down-converts a received RF signal to a quadrature intermediate frequency (IF) signal. The receiver further includes a dithering controller responsive to the quadrature IF signal generated by the primary LO. The dithering controller communicates a feedback signal back to the primary LO. The feedback signal controls the primary LO in order to offset down-conversion of the RF signal by the quadrature IF signal. The dithering controller offsets the primary LO from a zero-IF signal in order to reduce a phase and gain error of the quadrature IF signal.