Abstract: In at least one embodiment, a method for measuring a distance between a first communications device including a first local oscillator and a second communications device including a second local oscillator includes unwrapping N phase values to generate N unwrapped phase values. N is an integer greater than one. Each of the N phase values indicate an instantaneous phase of a received signal. The method includes averaging the N unwrapped phase values to generate an average phase value. The method includes wrapping the average phase value to generate a final phase measurement of the first local oscillator with respect to the second local oscillator.

Abstract: In at least one embodiment, a method for measuring a distance between a first communications device including a first local oscillator and a second communications device including a second local oscillator includes unwrapping N phase values to generate N unwrapped phase values. N is an integer greater than one. Each of the N phase values indicate an instantaneous phase of a received signal. The method includes averaging the N unwrapped phase values to generate an average phase value. The method includes wrapping the average phase value to generate a final phase measurement of the first local oscillator with respect to the second local oscillator.

Abstract: In at least one embodiment, a method for measuring a distance between a first communications device including a first local oscillator and a second communications device including a second local oscillator includes unwrapping N phase values to generate N unwrapped phase values. N is an integer greater than one. Each of the N phase values indicate an instantaneous phase of a received signal. The method includes averaging the N unwrapped phase values to generate an average phase value. The method includes wrapping the average phase value to generate a final phase measurement of the first local oscillator with respect to the second local oscillator.

Abstract: A method for communicating between a first radio frequency communications device including a first local oscillator and a second radio frequency communications device including a second local oscillator includes generating phase values based on samples of a received signal. Each of the phase values indicates an instantaneous phase of the received signal. The method includes unwrapping the phase values to generate unwrapped phase values. The method includes generating frequency offset estimates based on the unwrapped phase values. The method includes generating an average frequency offset estimate based on the unwrapped phase values. The method includes wrapping the average frequency offset estimate to generate a residual frequency offset estimate. The method includes adjusting the first local oscillator based on the residual frequency offset estimate, thereby reducing a frequency offset between the first local oscillator and the second local oscillator.

Abstract: A receiver includes a first discrete Fourier transform (DFT) block to perform a first single tone DFT on a positive tone associated with a sounding sequence. A second DFT block performs a second single tone DFT on a negative tone associated with the sounding sequence. A DFT coefficient generation block generates first DFT coefficients based on a nominal frequency of the positive tone and an estimated frequency offset between a transmitter frequency and a receiver frequency. The DFT coefficient generation block generates second DFT coefficients based on a nominal frequency of the negative tone and the estimated frequency offset. Multipliers in the DFT blocks multiply I and Q values of the sounding sequence with the coefficients. Accumulators in the DFT blocks accumulate multiplier outputs. An arctan function receives averaged accumulated values from the first and second DFT blocks and supplies first and second phase values used to calculate fractional timing.

Abstract: A mixer in a receiver converts a sounding sequence of alternating ones and zeros to an intermediate frequency signal. A digital mixer converts the intermediate frequency signal to a baseband signal that contains a positive tone and a negative tone. A frequency offset correction circuit generates frequency offset corrections based on frequency offset estimates of the frequency offset between a transmitter of the sounding sequence and the receiver. A frequency adjustment circuit adjusts a frequency of the mixer or the digital mixer to thereby center the positive tone and the negative tone around DC. DFT circuits perform single bin DFTs respectively centered on the positive and negative tones. Phases of the positive and negative tones are calculated based on outputs of the DFT circuits and the phases are used to determine fractional time value associated with a distance measurement between the transmitter and receiver.

Abstract: A method for communicating between a first radio frequency communications device including a first local oscillator and a second radio frequency communications device including a second local oscillator includes receiving a packet using a receiver of the first radio frequency communications device. The method includes detecting an average frequency offset based on sequential samples of the packet. The method includes applying a first adjustment to the first local oscillator to reduce a frequency offset between the first local oscillator and the second local oscillator. The first adjustment is based on the average frequency offset. The method includes, after adjusting the first local oscillator, transmitting a second packet to the second radio frequency communications device by the first radio frequency communications device using the first adjustment and the first local oscillator.

Abstract: A method for operating a radio frequency communications system includes, while operating a first radio frequency communications device in a calibration mode, for each setting of a plurality of settings of a programmable gain amplifier in a receiver of the first radio frequency communications device configured in a zero-intermediate frequency mode of operation, generating an estimate of a DC offset in each of a plurality of digital samples received from an analog circuit path including the programmable gain amplifier, and storing in a corresponding storage element, a compensation value based on the estimate.

Abstract: A method for communicating between a first radio frequency communications device including a first local oscillator and a second radio frequency communications device including a second local oscillator includes generating phase values based on samples of a received signal. Each of the phase values indicates an instantaneous phase of the received signal. The method includes unwrapping the phase values to generate unwrapped phase values. The method includes generating frequency offset estimates based on the unwrapped phase values. The method includes generating an average frequency offset estimate based on the unwrapped phase values. The method includes wrapping the average frequency offset estimate to generate a residual frequency offset estimate. The method includes adjusting the first local oscillator based on the residual frequency offset estimate, thereby reducing a frequency offset between the first local oscillator and the second local oscillator.

Abstract: A method for communicating between a first radio frequency communications device including a first local oscillator and a second radio frequency communications device including a second local oscillator includes receiving a packet using a receiver of the first radio frequency communications device. The method includes detecting an average frequency offset based on sequential samples of the packet. The method includes applying a first adjustment to the first local oscillator to reduce a frequency offset between the first local oscillator and the second local oscillator. The first adjustment is based on the average frequency offset. The method includes, after adjusting the first local oscillator, transmitting a second packet to the second radio frequency communications device by the first radio frequency communications device using the first adjustment and the first local oscillator.

Abstract: A receiver includes a first discrete Fourier transform (DFT) block to perform a first single tone DFT on a positive tone associated with a sounding sequence. A second DFT block performs a second single tone DFT on a negative tone associated with the sounding sequence. A DFT coefficient generation block generates first DFT coefficients based on a nominal frequency of the positive tone and an estimated frequency offset between a transmitter frequency and a receiver frequency. The DFT coefficient generation block generates second DFT coefficients based on a nominal frequency of the negative tone and the estimated frequency offset. Multipliers in the DFT blocks multiply I and Q values of the sounding sequence with the coefficients. Accumulators in the DFT blocks accumulate multiplier outputs. An arctan function receives averaged accumulated values from the first and second DFT blocks and supplies first and second phase values used to calculate fractional timing.

Abstract: In at least one embodiment, a method for measuring a distance between a first communications device including a first local oscillator and a second communications device including a second local oscillator includes unwrapping N phase values to generate N unwrapped phase values. N is an integer greater than one. Each of the N phase values indicate an instantaneous phase of a received signal. The method includes averaging the N unwrapped phase values to generate an average phase value. The method includes wrapping the average phase value to generate a final phase measurement of the first local oscillator with respect to the second local oscillator.

Abstract: A method for operating a radio frequency communications system includes, while operating a first radio frequency communications device in a calibration mode, for each setting of a plurality of settings of a programmable gain amplifier in a receiver of the first radio frequency communications device configured in a zero-intermediate frequency mode of operation, generating an estimate of a DC offset in each of a plurality of digital samples received from an analog circuit path including the programmable gain amplifier, and storing in a corresponding storage element, a compensation value based on the estimate.

Abstract: A mixer in a receiver converts a sounding sequence of alternating ones and zeros to an intermediate frequency signal. A digital mixer converts the intermediate frequency signal to a baseband signal that contains a positive tone and a negative tone. A frequency offset correction circuit generates frequency offset corrections based on frequency offset estimates of the frequency offset between a transmitter of the sounding sequence and the receiver. A frequency adjustment circuit adjusts a frequency of the mixer or the digital mixer to thereby center the positive tone and the negative tone around DC. DFT circuits perform single bin DFTs respectively centered on the positive and negative tones. Phases of the positive and negative tones are calculated based on outputs of the DFT circuits and the phases are used to determine fractional time value associated with a distance measurement between the transmitter and receiver.

Abstract: Various embodiments of the present technology may comprise methods and apparatus for a light sensor with a precharge circuit, such as for charging an internal node of a sensor to a starting voltage equal to an ending voltage of a different sensor. The methods and apparatus may comprise sequentially reading out the voltages of photosensitive elements and selectively activating the precharge circuit of one sensor during readout of the last photosensitive element of a different sensor.

Abstract: Various embodiments of the present technology may comprise methods and apparatus for a light sensor with a precharge circuit, such as for charging an internal node of a sensor to a starting voltage equal to an ending voltage of a different sensor. The methods and apparatus may comprise sequentially reading out the voltages of photosensitive elements and selectively activating the precharge circuit of one sensor during readout of the last photosensitive element of a different sensor.

Abstract: A system to generate an oscillator signal. The system includes a multi-stage oscillator, where each stage generates an output. The system also includes a first weighting circuit coupled to the multi-stage oscillator. The first weighting circuit taps the outputs of at least some of the stages and applies a first variable weighting factor to each output of the tapped stages to generate a first weighted output for each of the tapped stages. The system also includes a first summing circuit coupled to the first weighting circuit. The first summing circuit sums the first weighted outputs of the tapped stages to produce the oscillator signal.

Abstract: A circuit includes a ring oscillator component and a phase selecting component. The ring oscillator component outputs a clock signal having a clock frequency, fCLK, and has a number n of delay components connected in series. The phase selecting component outputs a feedback clock signal, and has a switching component. The switching component can be in a first state and a second state, and can switch from the first state to the second state. The switching component outputs, in the first state, an output of a first delay component such that a signal output from the first delay component is the feedback clock signal having a first phase. The switching component outputs, in the second state, an output of a second delay component such that a signal output from the second delay component is the feedback clock signal having a second phase.

Abstract: An analog floating-gate electrode in an integrated circuit, and method of fabricating the same, in which trapped charge can be stored for long durations. The analog floating-gate electrode is formed in a polycrystalline silicon gate level, doped n-type throughout its length, and includes portions serving as gate electrodes of n-channel and p-channel MOS transistors; a plate of a metal-to-poly storage capacitor; and a plate of poly-to-active tunneling capacitors. The p-channel MOS transistor includes a buried channel region, formed by way of ion implantation, disposed between its source and drain regions. Silicide-block silicon dioxide blocks the formation of silicide cladding on the electrode, while other polysilicon structures in the integrated circuit are silicide-clad.

Abstract: An analog floating-gate electrode in an integrated circuit, and method of fabricating the same, in which trapped charge can be stored for long durations. The analog floating-gate electrode is formed in a polycrystalline silicon gate level, doped n-type throughout its length, and includes portions serving as gate electrodes of n-channel and p-channel MOS transistors; a plate of a metal-to-poly storage capacitor; and a plate of poly-to-active tunneling capacitors. The p-channel MOS transistor includes a buried channel region, formed by way of ion implantation, disposed between its source and drain regions. Silicide-block silicon dioxide blocks the formation of silicide cladding on the electrode, while other polysilicon structures in the integrated circuit are silicide-clad.