L-3 Communications Integrated Systems L.p.

L-3 Integrated Systems Company

L-3 Communications Corporation

Gerald Lothair Fudge

Mark Allen Chivers

Sujit Ravindran

James Edward Harvey

Frank A Boyle

Chen-Chu Alex Yeh

Antone Lee Kusmanoff

Ross A McClain, Jr

Mark L Wood

Ross E Bland

Deepak Prasanna

Scott Michael Burkart

Calvin A Coffey

Alex Yeh

Alex Chen-Chu Yeh

Boyd E Gallatin

Ray Maleh

Christopher A Fox

E Scott Baker

Cameron Johnson

Ryan Lange

Mark A Chivers

Nyquist folding receivers (NYFRs) are disclosed that use three or more non-modulated sampling clock signals with different frequencies to produce multiple projections in a sampled output. Using these three or more different sampling clock signals, multiple Nyquist zones are aliased together while still allowing signals from different Nyquist zones to be separated and identified in later processing based upon the sampling provided by the different sampling clock signals. NYFR sampling receivers are also disclosed that simultaneously produce multiple separate and different parallel channels from an input signal, with each different channel having a different sampling clock sampling rate from the other channels so as to generate a respective folding pattern that is different from the folding pattern generated by the respective RF sampling rate of each of the other simultaneous and parallel channels. A particular signal may be separated and identified by matching it to the respective different folding patterns in each of the simultaneous multiple different parallel channels.

Multiple clock sampling for Nyquist folded sampling receivers

Systems and methods are disclosed for detecting and/or measuring signals contained in modulated sample data, and that may be implemented in one embodiment to detect and measure signals by producing a representation and/or visualization of the signal information of the wide band spectral environment. Signals may be detected and/or measured by demodulating and estimating signal spectra from the modulated sample data that contain the individual signals, and by then forming a frequency representation of the demodulated Nyquist zone spectral estimates into a visual representation in which the frequency of the original signals is visible or otherwise indicated.

Systems and methods for signal detection and estimation

A computing system () includes a plurality of hardware computing resources (-) controlled at least in part by a plurality of autonomous computing agents (). Each autonomous computing agent () includes or has access to operating information including processing information (), resource information (), optimization information (), and communication information (). The computing agents () collaborate to optimize performance of the system () and to assign computing tasks to the resources (-) according to a predetermined strategy. The predetermined strategy may seek to optimize speed, power, or communication efficiency of the system. Each agent () may optimize performance of the system () by assigning tasks to best-fit resources or by reconfiguring one or more resources. The agents () may collaborate to optimize performance of the system () by sharing resource and task information and assigning tasks to best-fit resources based on the shared information, reconfiguring one or more resources based on the shared information, or both.

Heterogeneous reconfigurable agent compute engine (HRACE)

Systems and methods that provide clock jitter compensation architectures that improve the performance of direct radio frequency (RF) receivers by injecting a calibration tone into the received radio frequency (RF) signals in order to help identify and then compensate for the clock jitter noise. After injecting the tone, the jitter noise going through the direct RF bandpass sampling receiver is estimated using a narrow bandwidth filter, and the received signals are further processed and demodulated depending on the Nyquist zone of the received signal. The relative modulation factor for the modulation is computed and then applied to the Nyquist zone to de jitter that particular Nyquist zone.

System and method for clock jitter compensation in direct RF receiver architectures

Improved spur reduction architectures that improve linearity in direct radio frequency (RF) receiver architectures. Non-uniform sampling in the form of sampling clock phase (or frequency) modulation is used to induce phase (or frequency) modulation on signals that are being received from a given Nyquist zone. At the output of the ADC (analog-to-digital converter), the signals are de-modulated to remove the induced modulation based on the Nyquist zone that is being received. The de-modulation process results in non-desired spurious artifacts (interfering leakage signals and ADC spurs) being spread in the frequency domain. Strong spurious artifacts may be removed after measuring the induced modulation and de-modulating. For the case of weak spurious artifacts, the de-modulation for the desired Nyquist zone spread these signals in the frequency domain. Induced modulation on signals may also provide a dithering effect on the ADC.

System and method for improved spur reduction in direct RF receiver architectures

RF sampling receivers are disclosed that employ multiple sampling clocks to produce multiple projections. In operation, a Nyquist folded receiver (NYFR) may be implemented that utilizes at least one modulated sampling clock in combination with one or more other modulated or non-modulated sampling clocks to identify received signals. In such an embodiment, one or more clock modulations may be used to induce frequency modulations that are Nyquist zone dependent, and multiple Nyquist zones may be aliased together while still allowing for signals from different Nyquist zones to be separated and identified.

Multiple projection sampling for RF sampling receivers

Systems and methods are disclosed that provide ultra-wideband frequency hopping spread spectrum (UWB-FHSS) solutions for transmit and receive architectures. These UWB-FHSS transmit and receive architectures can transmit signals over an extremely wide bandwidth while using a relatively slow analog-to-digital converter (ADC) without suffering from unacceptable performance degradation. For example, ADCs can be used having sample rates lower than standard Nyquist criteria would require for the bandwidth of the spread spectrum utilized.

Wideband frequency hopping spread spectrum transmitters and related methods

Ultra-wideband frequency hopping spread spectrum (UWB-FHSS) solutions are used for receive architectures. These UWB-FHSS receive architectures can receive signals transmitted over an extremely wide bandwidth while using a relatively slow analog-to-digital converter (ADC) without suffering from unacceptable performance degradation. For example, ADCs can be used having sample rates lower than standard Nyquist criteria would require for the bandwidth of the spread spectrum utilized.

Wideband frequency hopping spread spectrum receivers and related methods

Ultra-wideband frequency hopping spread spectrum (UWB-FHSS) solutions are used for transceiver architectures. These UWB-FHSS transceiver architectures can transmit and accurately digitize frequency hops over an extremely wide bandwidth while using a relatively slow analog-to-digital converter (ADC) without suffering from unacceptable performance degradation. For example, ADCs can be used having sample rates lower than standard Nyquist criteria would require for the bandwidth of the spread spectrum utilized.

Wideband frequency hopping spread spectrum transceivers and related methods

Systems and methods for detecting and/or identifying signals that employ streaming processing to generate time-frequency surfaces by sampling a datastream according to a temporal structure that may be chosen as needed. The sampled datastream may be correlated with a set of templates that span the band of interest in a continuous manner, and used to generate time-frequency surfaces from irregularly sampled data with arbitrary structure that has been sampled with non-constant and non-Nyquist sampling rates where such non-constant rates are needed or desired.

Systems and methods for construction of time-frequency surfaces and detection of signals

Sampling may be employed to cancel an analog input radio frequency (RF) signal by using an upconverted analog cancellation RF signal to cancel the analog input RF signal at the sample instances. At least two sampling paths may be employed, a signal path and a cancel path, and direct RF bandpass sampling may be included in both the signal and cancel paths.

Interference cancellation for reconfigurable direct RF bandpass sampling interference cancellation

Systems and methods for interference cancellation in which a first signal having a first frequency may be cancelled with a second frequency having a second and different (e.g., lower) frequency by employing sampling to cancel the first signal with the separate signal at the sample instances.

Systems and methods for interference cancellation

A system for characterizing a compressed sensing apparatus is described which broadly includes a random vector generator for generating an input vector, a waveform generator in communication with the random vector generator for converting the input vector into an analog signal, a compressed sensing apparatus in communication with the digital-to-analog converter for determining a digital bit stream from the analog signal, a serial-to-parallel converter for converting the digital bit stream into an input vector; and an electronic processor in communication with the random number generator and the serial-to-parallel converter configured for determining a compressed sensing matrix.

Compressed sensing characterization system and method

The present invention is a method and computer program for equalizing group delay and magnitude of a system for which a system response is known. The method and computer program are implemented via a finite impulse response ('FIR') filter for the system, and the method broadly comprises the steps of: evaluating a desired response for the system as a function of an amplitude of the system and a phase of the system; separating the phase of the system into a linear component and a non-linear component; performing a first optimization by minimizing a weighted error between a desired response for the system and a cascaded response for the system as a function of an equalizing filter and a phase slope so as to obtain at least one local smallest error E(&#x3a9;) as a function of phase slope; and once the local smallest error E(&#x3a9;) is known, performing a second optimization to locate any existing global smallest error, wherein the global smallest error is within a set distance from the local smallest error.

Method and computer program for group delay and magnitude equalization with relaxed phase slope constraint

A swept bandpass filter for receiving frequency varying input signals is disclosed. More particularly, a swept bandpass filter frequency modulated continuous wave (FMCW) receiver and related method are disclosed that provide an efficient solution for FMCW signals. The swept bandpass architecture eliminates the need for front-end mixing circuitry and allows for sampling across one or more Nyquist zones within the swept frequency band.

Growing community of inventors

Rockwall, TX, United States of America

Gerald Lothair Fudge