Abstract: A system for self-interference cancellation includes a frequency downconverter that decomposes a sampled RF transmit signal into an in-phase transmit signal and a quadrature transmit signal; a first analog vector modulator that scales the transmit signals to generate first scaled transmit signals; a second analog vector modulator that scales delayed transmit signals to generate second scaled transmit signals; a frequency upconverter that recomposes the scaled transmit signals into an RF self-interference cancellation signal; and a receive coupler that that combines the RF self-interference cancellation signal with a RF receive signal to reduce self-interference.

Abstract: A system for linearized-mixer interference mitigation includes first and second linearized frequency downconverters; a sampling analog interference filtering system that, in order to remove interference in the transmit band, filters the sampled BB transmit signal to generate a cleaned BB transmit signal; an analog interference canceller that transforms the cleaned BB transmit signal to a BB interference cancellation signal; and a first signal coupler that combines the BB interference cancellation signal and the BB receive signal in order to remove a first portion of receive-band interference.

Abstract: A system for interference mitigation includes: a first transmit coupler; a receive-band noise cancellation system; a first transmit-band filter; a second transmit coupler; a first receive coupler; a transmit-band noise cancellation system; a first receive-band filter; and a second receive coupler.

Abstract: A system for digital self-interference cancellation includes a filter that generates a reduced-noise digital residue signal; a channel estimator that generates a current self-interference channel estimate from a digital transmit signal, the reduced-noise digital residue signal, and past self-interference channel estimates; a controller that dynamically sets the digital transform configuration in response to changes in a controller-sampled digital residue signal; a predictor that modifies output of the channel estimator to compensate for a first time delay incurred in tuning the system for digital self-interference cancellation; and a channel memory that stores the past self-interference channel estimates.

Abstract: A method for adaptively-tuned digital self-interference cancellation includes generating a digital self-interference cancellation signal from a digital transmit signal based on a transform configuration; combining the digital self-interference cancellation signal with a receive signal to form a digital residue signal; generating a composite residue signal from the digital residue signal and the digital transmit signal; and updating the transform configuration based on the composite residue signal.

Abstract: A system for enhancing isolation in coexisting time-division duplexed (TDD) transceivers includes: a blocker canceller that transforms a transmit signal of a TDD transceiver into a blocker cancellation signal configured to remove transmit-band interference in a receive signal; a first filter that filters the blocker cancellation signal; a second filter that filters the transmit signal; and a transmit-noise canceller that transforms the filtered transmit signal into a transmit noise cancellation signal configured to remove receive-band interference in the receive signal.

Abstract: An analog time delay filter circuit including a first delay circuit block arranged in a modular layout, having a first time delay filter, a first input, a first output, and first and second pass-throughs; and a second delay circuit block arranged in the same modular layout, having a second time delay filter, a second input, a second output, and third and fourth pass-throughs.

Abstract: A multilayer fringe capacitor includes first and second interdigitated capacitor electrodes, both parallel to and intersecting a first planar surface; third and fourth interdigitated capacitor electrodes, the first and second electrodes parallel to and separated by a non-zero distance from the third and fourth electrodes; a first set of coupling vias that electrically couples the first electrode to the third electrode; and a second set of coupling vias that electrically couples the second electrode to the fourth electrode.

Abstract: A system for self-interference cancellation includes a frequency downconverter that decomposes a sampled RF transmit signal into an in-phase transmit signal and a quadrature transmit signal; a first analog vector modulator that scales the transmit signals to generate first scaled transmit signals; a second analog vector modulator that scales delayed transmit signals to generate second scaled transmit signals; a frequency upconverter that recomposes the scaled transmit signals into an RF self-interference cancellation signal; and a receive coupler that that combines the RF self-interference cancellation signal with a RF receive signal to reduce self-interference.

Abstract: A system for interference mitigation including a transmit coupler that samples the RF transmit signal to create a sampled RF transmit signal; a transmit analog canceller that transforms the RF transmit signal to an RF interference cancellation signal, according to a first configuration state; a first receive coupler that combines the RF interference cancellation signal and the RF receive signal to generate a composite RF receive signal; a sampling analog interference filtering system that, in order to remove interference in the transmit band, filters the sampled RF transmit signal to generate a cleaned transmit signal; a first frequency downconverter that converts the transmit signal to a BB transmit signal; a second frequency downconverter that converts the composite RF receive signal to a composite BB receive signal; and an analog-to-digital converter that converts the transmit signal to a digital transmit signal.

Abstract: A system for wired analog self-interference cancellation includes a coarse delayer that delays a sampled RF transmit signal by a first delay amount; a frequency downconverter that downconverts the sampled RF transmit signal to IF; a first canceller tap group comprising a first per-tap-group delayer, a first sampling coupler, a first per-tap delayer, and first and second analog vector modulators that generates an IF self-interference cancellation signal; a frequency upconverter that upconverts the IF self-interference cancellation signal to RF; and a receive coupler that combines the RF self-interference cancellation signal with the RF receive signal, reducing self-interference.

Abstract: A system for digital self-interference cancellation includes a filter that generates a reduced-noise digital residue signal; a channel estimator that generates a current self-interference channel estimate from a digital transmit signal, the reduced-noise digital residue signal, and past self-interference channel estimates; a controller that dynamically sets the digital transform configuration in response to changes in a controller-sampled digital residue signal; and a channel memory that stores the past self-interference channel estimates.

Abstract: A system for integrated self-interference cancellation, comprising a transmit coupler, coupled to a transmit signal, that samples the transmit signal to create a sampled transmit signal; an analog self-interference canceller, coupled to the transmit coupler, comprising a controller; a signal divider, that splits the sampled transmit signal into a set of signal components; a set of phase shifters, wherein a phase shifter of the set shifts a signal component of the set of signal components by a total phase shift value; a set of scalers, wherein a scaler of the set scales the signal component by a total scale factor; a signal combiner, that combines the set of signal components into a self-interference cancellation signal; and a receive coupler, coupled to a receive signal, that combines the self-interference cancellation signal with the receive signal to remove a portion of self-interference present in the receive signal.

Abstract: A system for interference mitigation includes: a first transmit coupler; a receive-band noise cancellation system; a first transmit-band filter; a second transmit coupler; a first receive coupler; a transmit-band noise cancellation system; a first receive-band filter; and a second receive coupler.

Abstract: A system for frequency isolation modified self-interference cancellation includes a transmit coupler, that samples an RF transmit signal; an RF self-interference canceller that transforms the sampled RF transmit signal to an RF self-interference cancellation signal; a receive coupler that combines the RF self-interference cancellation signal with the RF receive signal to form a reduced-interference receive signal; and a frequency shifter that frequency shifts only one of the RF transmit signal and the reduced-interference receive signal.

Abstract: A system for interference mitigation including a transmit coupler that samples the RF transmit signal to create a sampled RF transmit signal; a transmit analog canceller that transforms the RF transmit signal to an RF interference cancellation signal, according to a first configuration state; a first receive coupler that combines the RF interference cancellation signal and the RF receive signal to generate a composite RF receive signal; a sampling analog interference filtering system that, in order to remove interference in the transmit band, filters the sampled RF transmit signal to generate a cleaned transmit signal; a first frequency downconverter that converts the transmit signal to a BB transmit signal; a second frequency downconverter that converts the composite RF receive signal to a composite BB receive signal; and an analog-to-digital converter that converts the transmit signal to a digital transmit signal.

Abstract: A system for wired analog self-interference cancellation includes a coarse delayer that delays a sampled RF transmit signal by a first delay amount; a frequency downconverter that downconverts the sampled RF transmit signal to IF; a first canceller tap group comprising a first per-tap-group delayer, a first sampling coupler, a first per-tap delayer, and first and second analog vector modulators that generates an IF self-interference cancellation signal; a frequency upconverter that upconverts the IF self-interference cancellation signal to RF; and a receive coupler that combines the RF self-interference cancellation signal with the RF receive signal, reducing self-interference.

Abstract: A method for adaptively-tuned digital self-interference cancellation includes generating a digital self-interference cancellation signal from a digital transmit signal based on a transform configuration; combining the digital self-interference cancellation signal with a receive signal to form a digital residue signal; generating a composite residue signal from the digital residue signal and the digital transmit signal; and updating the transform configuration based on the composite residue signal.

Abstract: A multilayer fringe capacitor includes first and second interdigitated capacitor electrodes, both parallel to and intersecting a first planar surface; third and fourth interdigitated capacitor electrodes, the first and second electrodes parallel to and separated by a non-zero distance from the third and fourth electrodes; a first set of coupling vias that electrically couples the first electrode to the third electrode; and a second set of coupling vias that electrically couples the second electrode to the fourth electrode.

Abstract: A relay including a first transmitter that converts a first digital transmit signal to a first analog transmit signal, a first receiver that converts a first analog receive signal to a first digital receive signal, a second transmitter that converts a second digital transmit signal to a second analog transmit signal, a second receiver that converts a second analog receive signal to a second digital receive signal, and a self-interference canceller that generates a first self-interference cancellation signal based on at least one of the first digital transmit signal and the first analog transmit signal, and combines the first self-interference cancellation signal with at least one of the first digital receive signal and the first analog receive signal.