A linear, low noise, high quality factor (Q) and widely tunable notch filter circuit includes one or more first reactive elements coupled between a first filter node and a first node. The notch filter circuit further includes a multi-branch circuit having multiple parallel branches and coupled between the first node and a second node. Each branch of the multi-branch circuit includes at least a switch coupled to a variable capacitor. A notch frequency of the notch filter circuit is tunable by adjusting a capacitance of the variable capacitor.

Ultra-Wideband (UWB) technology exploits modulated coded impulses over a wide frequency spectrum with very low power over a short distance for digital data transmission. Such UWB systems through their receivers may operate in the presence of interfering signals and should provide for robust communications. Accordingly, an accurate and sharp filter that operates at low power is required and beneficially one that does not require a highly accurate power heavy clock. Further, many UWB applications require location and/or range finding of other elements and it would therefore be beneficial to provide a UWB based range finding and/or location capability removing the requirement to add additional device complexity and, typically significant, power consumption.

A single receiver to process multiple signals to achieve carrier aggregation includes a main path, an auxiliary path and one or more local oscillators. The main path has an input that receives an input signal. The input signal includes non-contiguous wanted signals and a jammer signal. The single receiver also includes an output coupled to a modem. The output provides the wanted signals to the modem. The auxiliary path is coupled to ground and includes an N-path filter. The N-path filter has multiple mixers. The N-path filter filters out at least a portion of the jammer signal in one or more gaps between the non-contiguous wanted signals in a same frequency band. The one or more local oscillators are coupled to the main path and/or the auxiliary path to provide a first reference signal to the main path and/or to the N-path filter of the auxiliary path.

Ultra-Wideband (UWB) technology exploits modulated coded impulses over a wide frequency spectrum with very low power over a short distance for digital data transmission. Such UWB systems through their receivers may operate in the presence of interfering signals and should provide for robust communications. Accordingly, an accurate and sharp filter that operates at low power is required and beneficially one that does not require a highly accurate power heavy clock. Further, many UWB applications require location and/or range finding of other elements and it would therefore be beneficial to provide a UWB based range finding and/or location capability removing the requirement to add additional device complexity and, typically significant, power consumption.

Self-interference cancellers are provided. The self-interference cancellers can include multiple second-order, N-path G.sub.m-C filters. Each filter can be configured to cancel self-interference on a channel of a desired bandwidth. Each filter can be independently controlled using a variable transmitter resistance, a variable receiver resistance, a variable baseband capacitance, a variable transconductance, and a variable time shift between local oscillators that control switches in the filter. By controlling these variables, magnitude, phase, slope of magnitude, and slope of phase of the cancellers frequency responses can be controlled for self-interference cancellation. A calibration process is also provided for configuring the canceller.

A linear, low noise, high quality factor (Q) and widely tunable notch filter circuit includes one or more first reactive elements coupled between a first filter node and a first node. The notch filter circuit further includes a multi-branch circuit having multiple parallel branches and coupled between the first node and a second node. Each branch of the multi-branch circuit includes at least a switch coupled to a variable capacitor. A notch frequency of the notch filter circuit is tunable by adjusting a capacitance of the variable capacitor.

Systems and method are provided for implementing filters whose response automatically and continuously reconfigures between an all-pass response and a bandstop response as the power level of signals within their bandwidth changes. Embodiments of the present disclosure allow high power signals within a designable bandwidth to be strongly attenuated while minimally affecting signals in adjacent bandwidths and further allow low power signals in the designable bandwidth to pass with minimal attenuation.

The present technology relates to a notch filter capable of easily obtaining a desired frequency characteristic. In an N-path filter unit, any one of a plurality of N capacitors is selected as a signal path through which a signal passes, so that the capacitor serving as the signal path is temporally switched. A plurality of N-path filter units is cascade-connected and a capacitor is inserted to a connection point between the N-path filter units. The present technology may be applied to the notch filter which eliminates a blocker and the like, for example.

A sensor device includes: first sensors; second sensors which form capacitances with the first sensors; a sensor transmitter connected to the first sensors, where the sensor transmitter supplies driving signals to the first sensors; and a sensor receiver connected to the second sensors, where the sensor receiver receives sensing signals from the second sensors, and the sensor receiver includes a band pass filter which filters the sensing signals. The band pass filter includes: a first integrator including a first amplifier; a first high pass filter converter connected to a first input terminal, a second input terminal and a first output terminal of the first amplifier, where the first high pass filter converter time-divisionally provides N high pass filter conversion paths; and a first gain auxiliary component connected to the first input terminal and the first output terminal of the first amplifier while the first integrator performs an integral function.

A single receiver to process multiple signals to achieve carrier aggregation includes a main path, an auxiliary path and one or more local oscillators. The main path has an input that receives an input signal. The input signal includes non-contiguous wanted signals and a jammer signal. The single receiver also includes an output coupled to a modem. The output provides the wanted signals to the modem. The auxiliary path is coupled to ground and includes an N-path filter. The N-path filter has multiple mixers. The N-path filter filters out at least a portion of the jammer signal in one or more gaps between the non-contiguous wanted signals in a same frequency band. The one or more local oscillators are coupled to the main path and/or the auxiliary path to provide a first reference signal to the main path and/or to the N-path filter of the auxiliary path.