Abstract: An RF antenna feed module uses an optical feed network and photo-detectors to generate RF feed signals to drive a dual polarization RF antenna to produce an RF beam with a variable polarization state. The optical feed network and suitably the photo-detectors are monolithically fabricated PIC. Multiple modules may be configured to drive a dual polarization RF phased array. A single feed module can produce RF feed signals over a frequency range of at least 300 GHz.

Abstract: An RF antenna feed module uses an optical feed network and photo-detectors to generate RF feed signals to drive a dual polarization RF antenna to produce an RF beam with a variable polarization state. The optical feed network and suitably the photo-detectors are monolithically fabricated PIC. Multiple modules may be configured to drive a dual polarization RF phased array. A single feed module can produce RF feed signals over a frequency range of at least 300 GHz.

Abstract: A system for transmitting and receiving electromagnetic waves simultaneously. A portion of a signal to be transmitted through a transmitting antenna element is diverted from a transmit signal path, processed by an adjustable filter, and coupled into receive signal path. The adjustable filter is adjusted to approximate the channel that the leakage signals go through to get from the transmitter to the receiver so that the signal coupled into the receiving path through the filter partially cancels the parasitic leakage from the transmit signal path to the receive signal path.

Abstract: An apparatus for performing interference cancellation is disclosed, comprising: a first electro-optic (EO) modulator configured to modulate a received RF signal onto a first optical carrier signal to generate a first modulated signal; a plurality of base signal sources configured to generate a plurality of base signals; an optical combiner coupled to the plurality of base signal sources, the optical combiner being configured to combine the base signals into a second optical carrier signal; a second EO modulator configured to modulate a reference signal onto the second optical carrier signal to generate a second modulated signal; and a subtraction element that is coupled to the first EO modulator and the refractive element, the subtraction element being configured to subtract the tapped delay line signal from the first modulated signal to generate an output signal.

Abstract: An apparatus for performing interference cancellation is disclosed, comprising: a first electro-optic (EO) modulator configured to modulate a received RF signal onto a first optical carrier signal to generate a first modulated signal; a plurality of base signal sources configured to generate a plurality of base signals; an optical combiner coupled to the plurality of base signal sources, the optical combiner being configured to combine the base signals into a second optical carrier signal; a second EO modulator configured to modulate a reference signal onto the second optical carrier signal to generate a second modulated signal; and a subtraction element that is coupled to the first EO modulator and the refractive element, the subtraction element being configured to subtract the tapped delay line signal from the first modulated signal to generate an output signal.

Abstract: Method and apparatus for leakage signal cancellation in a simultaneous transmit and receive RF system includes: generating a digital transmit signal for transmission from the system; receiving a receive signal produced by reflection of the transmit signal from an object or generated by a second RF system; adaptively filtering the transmit signal by an adaptive finite input response (FIR) filter; calculating filter coefficients for the adaptive FIR filter in real-time at a different sampling rate; adaptively inputting the calculated filter coefficients to the adaptive FIR filter to generate a cancellation signal in real-time; and applying the cancellation signal to the receive signal to cancel leakage in the receive signal to generate an optimum receive signal.

Abstract: Method and apparatus for a phased array system including a plurality of unmanned aerial vehicles (UAVs) configured to fly in an array formation having an array lattice spacing. The UAVs can include a puck having a phased array element and a signal processing module configured to receive and process a signal to achieve for the array lattice spacing a spacing that is less than a wavelength of operation of the phased array elements.

Abstract: System and method for signal modulation. In one embodiment, a circuit includes a channel for carrying an analog RF signal, a phase offset circuit on the channel, and configured to receive a phase code for modifying the analog RF signal to produce a modified RF signal, and a feedforward cancellation path coupled in parallel to the phase offset circuit for canceling a portion of the modified analog signal.

Abstract: A reconfigurable discrete time analog signal processor includes a finite impulse response (FIR) filter configured to receive a portion of an RF transmit signal, to receive FIR coefficients, and to generate a leakage cancellation signal based on the portion of the RF transmit signal and the FIR coefficients, the FIR filter including sample and hold (SH) circuits configured to receive the portion of the RF transmit signal, to sample the portion of the RF transmit signal at successive sample times according to a sample clock, and to generate sampled analog voltage signals, and analog multipliers coupled to the SH circuits and configured to multiply the sampled analog voltage signals by binary multiplication factors to generate the leakage cancellation signal.

Abstract: A system for transmitting and receiving electromagnetic waves simultaneously. A portion of a signal to be transmitted through a transmitting antenna element is diverted from a transmit signal path, processed by an adjustable filter, and coupled into receive signal path. The adjustable filter is adjusted to approximate the channel that the leakage signals go through to get from the transmitter to the receiver so that the signal coupled into the receiving path through the filter partially cancels the parasitic leakage from the transmit signal path to the receive signal path.

Abstract: System and method for signal modulation. In one embodiment, a circuit includes a channel for carrying an analog RF signal, a phase offset circuit on the channel, and configured to receive a phase code for modifying the analog RF signal to produce a modified RF signal, and a feedforward cancellation path coupled in parallel to the phase offset circuit for canceling a portion of the modified analog signal.

Abstract: Method and apparatus for leakage signal cancellation in a simultaneous transmit and receive RF system includes: generating a digital transmit signal for transmission from the system; receiving a receive signal produced by reflection of the transmit signal from an object or generated by a second RF system; adaptively filtering the transmit signal by an adaptive finite input response (FIR) filter; calculating filter coefficients for the adaptive FIR filter in real-time at a different sampling rate; adaptively inputting the calculated filter coefficients to the adaptive FIR filter to generate a cancellation signal in real-time; and applying the cancellation signal to the receive signal to cancel leakage in the receive signal to generate an optimum receive signal.

Abstract: Method and apparatus for a phased array system including a plurality of unmanned aerial vehicles (UAVs) configured to fly in an array formation having an array lattice spacing. The UAVs can include a puck having a phased array element and a signal processing module configured to receive and process a signal to achieve for the array lattice spacing a spacing that is less than a wavelength of operation of the phased array elements.

Abstract: A reconfigurable discrete time analog signal processor includes a finite impulse response (FIR) filter configured to receive a portion of an RF transmit signal, to receive FIR coefficients, and to generate a leakage cancellation signal based on the portion of the RF transmit signal and the FIR coefficients, the FIR filter including sample and hold (SH) circuits configured to receive the portion of the RF transmit signal, to sample the portion of the RF transmit signal at successive sample times according to a sample clock, and to generate sampled analog voltage signals, and analog multipliers coupled to the SH circuits and configured to multiply the sampled analog voltage signals by binary multiplication factors to generate the leakage cancellation signal.

Abstract: Embodiments are directed to receiving an incoming signal, converting, by an analog circuit, the signal to a discrete time signal, applying, by the analog circuit, a transformation algorithm to the discrete time signal to obtain frequency samples of the discrete time signal, applying, by the analog circuit, a cross correlation algorithm to the frequency samples to obtain a cross spectral density (CSD), detecting, by the analog circuit, phase slopes associated with the CSD, and calculating an angle of arrival (AoA) of the incoming signal based on the phase slopes.

Abstract: An electronic analog memory system includes at least one analog programmable delay module configured to receive an input radio frequency pulse. The analog programmable delay module generates a time delayed output signal in response to applying at least one time delay to the input radio frequency pulse. A switching module is configured to selectively deliver the time delayed output signal to an output of the electronic analog memory system. The electronic analog memory system further includes an activity detector module configured to determine the amplitude of the input radio frequency pulse. The activity detector module also controls the switching module to deliver the time delayed output signal to the output in response to the at least one amplitude exceeding an amplitude threshold.

Abstract: Embodiments are directed to operating an analog signal processing circuit to emulate a Rotman lens. The analog signal processing circuit applies a plurality of time delays to a plurality of signals associated with a plurality of beam ports. The analog signal processing circuit forms a plurality of output beams for transmission by a plurality of array ports included in an array based on the time delayed signals by summing the time delayed signals. The time delays are based on a direction of transmission of the output beams.

Abstract: Embodiments are directed to operating an analog signal processing circuit to emulate a Rotman lens. The analog signal processing circuit applies a plurality of time delays to a plurality of signals associated with a plurality of beam ports. The analog signal processing circuit forms a plurality of output beams for transmission by a plurality of array ports included in an array based on the time delayed signals by summing the time delayed signals. The time delays are based on a direction of transmission of the output beams.

Abstract: An electronic analog memory system includes at least one analog programmable delay module configured to receive an input radio frequency pulse. The analog programmable delay module generates a time delayed output signal in response to applying at least one time delay to the input radio frequency pulse. A switching module is configured to selectively deliver the time delayed output signal to an output of the electronic analog memory system. The electronic analog memory system further includes an activity detector module configured to determine the amplitude of the input radio frequency pulse. The activity detector module also controls the switching module to deliver the time delayed output signal to the output in response to the at least one amplitude exceeding an amplitude threshold.

Abstract: Embodiments are directed to receiving an incoming signal, converting, by an analog circuit, the signal to a discrete time signal, applying, by the analog circuit, a transformation algorithm to the discrete time signal to obtain frequency samples of the discrete time signal, applying, by the analog circuit, a cross correlation algorithm to the frequency samples to obtain a cross spectral density (CSD), detecting, by the analog circuit, phase slopes associated with the CSD, and calculating an angle of arrival (AoA) of the incoming signal based on the phase slopes.