Patent classifications
H03H15/00
Adaptive analog parallel combiner
An adaptive analog parallel combiner circuit for receiver data recovery from a communication signal is provided. The circuit includes a summer that sums outputs of a plurality of filter taps in parallel, including zeroth and first through Nth filter taps, each filter tap having as input the communication signal or a version thereof, wherein N is a finite integer greater than or equal to two. The zeroth filter tap has an amplifier with gain controlled by a zeroth adaptive gain control coefficient, and each of the first through Nth filter taps having an all pass filter and gain controlled amplification, with gain controlled by a corresponding one of a first through Nth adaptive gain control coefficients and the all pass filter implementing a transfer function having a zero and a pole equaling each other and at a base frequency divided by a corresponding integer from one through N.
Discrete Time Filter Network
A discrete time filter network with an input signal connection and an output signal connection and comprising a capacitor bank with a plurality of history capacitors, and at least one sampling capacitor which operates at a predetermined cycling rate to couple to at least one history capacitor at a time, which history capacitor is selected from the capacitor bank so as to share electrical charge between such selected history capacitor and the sampling capacitor, wherein there is a plurality of sampling capacitors that are provided in the capacitor bank, and the discrete time filter network is provided with at least one switch network comprising a plurality of clock driven switches for making selected cyclical connections between the sampling capacitors and the history capacitors in the capacitor bank at the predetermined cycling rate.
Variable bandwidth filter
A variable bandwidth filter is described herein, wherein a bandwidth of a passband of the variable bandwidth filter is dynamically tunable. The variable bandwidth tuner is implemented on a CMOS chip, and acts to filter analog signals. The variable bandwidth filter comprises a plurality of finite impulse response (FIR) filters, wherein each FIR filter comprises a plurality of tunable transconductors. The tunable transconductors are tunable in their gain.
Discrete time analog signal processing for simultaneous transmit and receive
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.
Discrete time analog signal processing for simultaneous transmit and receive
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.
Receiver, communication unit, and method for down-converting a radio frequency signal
There is provided a communication receiver comprising: an input for receiving a radio frequency, RF, input signal; and at least one finite impulse response, FIR, discrete time filter, DTF. The at least one FIR DTF comprises: an input circuit comprising an input port for sampling the RF input signal at a sampling frequency that is comparable to the input RF input signal; and N parallel branches, each branch having a set of input unit sampling capacitances, where each unit sampling capacitance is independently selectively coupleable to an output summing node. The input circuit is configured to convert an equivalent input impedance of the at least one FIR DTF around the sampling frequency to a real impedance.
Receiver, communication unit, and method for down-converting a radio frequency signal
There is provided a communication receiver comprising: an input for receiving a radio frequency, RF, input signal; and at least one finite impulse response, FIR, discrete time filter, DTF. The at least one FIR DTF comprises: an input circuit comprising an input port for sampling the RF input signal at a sampling frequency that is comparable to the input RF input signal; and N parallel branches, each branch having a set of input unit sampling capacitances, where each unit sampling capacitance is independently selectively coupleable to an output summing node. The input circuit is configured to convert an equivalent input impedance of the at least one FIR DTF around the sampling frequency to a real impedance.
Gm-C filter and multi-phase clock circuit
Described herein is a power-efficient Gm-C filter, wherein the Gm-C filter includes several operational transconductance amplifiers (OTAs). In an example, at least two of the OTAs share a common bias current. Further, output of one of the OTAs is used to bias another one of the OTAs. Also described herein is a power-efficient clock generator circuit that is configured to output non-overlapping clock signals. The clock generator circuit includes a ring oscillator circuit, which includes several inverter stages. The clock generator circuit is well-suited for controlling operation of switches.
Equalizer circuit and receiving apparatus using the same
An equalizer circuit includes an phase-to-phase connectors including an phase-to-phase capacitor and four phase-to-phase switches, four output buffers, and control signal generation circuitry. One terminal of each phase-to-phase switches is connected to one of four connection paths on which four conversion signals being different in phase by 90 are input. The other one terminal of each phase-to-phase switches is connected to the phase-to-phase capacitor. Each output buffer is connected to one of the four connection paths and outputs an output signal. The control signal generation circuitry outputs control signals to control turning-on/off of the respective four phase-to-phase switches. A closing of the first, second, third, and fourth phase-to-phase switches are started from any one of phase-to-phase switches in one of a first ascending circulation and a first descending circulation based on the 4-phase control signals.
Charge sharing filter
A charge sharing filter includes a rotating capacitor, and a plurality of elementary filters, each elementary filter comprising: an elementary switch coupled between a first node of the respective elementary filter and a second node of the respective elementary filter; and a history capacitor coupled to the first node of the respective elementary filter, wherein the second nodes of the plurality of elementary filters are interconnected with the rotating capacitor in one interconnecting node.