A method of operating a seamless physical access control system comprises transferring communication session information using an out-of-band (OOB) communication channel of a smart ultra-wide band (UWB) capable device; establishing a secure OOB communication channel between the smart UWB capable device and a reader device using the communication session information; determining that a UWB enabled application of the smart UWB capable device needs secure ranging; establishing a secure UWB communication channel between the smart UWB capable device and the reader device; and transferring ranging information from a secure component of the smart UWB capable device to the reader device via the secure UWB communication channel.

Localization systems and methods for transmitting timestampable localization signals from anchors according to one or more transmission schedules. The transmission schedules may be generated and updated to achieve desired positioning performance. For example, one or more anchors may transmit localization signals at a different rate than other anchors, the anchor transmission order can be changed, and the signals can partially overlap. In addition, different transmission parameters may be used to transmit two localization signals at the same time without interference. A self-localizing apparatus is able to receive the localization signals and determine its position. The self-localizing apparatus may have a configurable receiver that can select to receive one of multiple available localization signals. The self-localizing apparatuses may have a pair of receivers able to receive two localization signals at the same time. A bridge anchor may be provided to enable a self-localizing apparatus to seamlessly transition between two localization systems.

Localization systems and methods for transmitting timestampable localization signals from anchors according to one or more transmission schedules. The transmission schedules may be generated and updated to achieve desired positioning performance. For example, one or more anchors may transmit localization signals at a different rate than other anchors, the anchor transmission order can be changed, and the signals can partially overlap. In addition, different transmission parameters may be used to transmit two localization signals at the same time without interference. A self-localizing apparatus is able to receive the localization signals and determine its position. The self-localizing apparatus may have a configurable receiver that can select to receive one of multiple available localization signals. The self-localizing apparatuses may have a pair of receivers able to receive two localization signals at the same time. A bridge anchor may be provided to enable a self-localizing apparatus to seamlessly transition between two localization systems.

A system and method for generating communications waveforms that can operate in congested frequency spaces and in applications in which the receiver is moving with respect to the transmitter is provided. In one or more examples, each symbol to be encoded and transmitted is converted into a sequence of frequency chirps. The sequence of frequencies used by the sequence of chirps is based on the symbol that is to be encoded. Each chirp can have a center frequency, and the frequency can be swept over the duration of the chirp. In this way each chirp can have a varying frequency over the duration of the chirp, but the phase of the chirp can be continuous throughout the duration of the chirp. The bandwidth and sweep rate of the chirp can be based on the expected maximum velocity of the receiver and the transmitter relative to one another.

A system and method for generating communications waveforms that can operate in congested frequency spaces and in applications in which the receiver is moving with respect to the transmitter is provided. In one or more examples, each symbol to be encoded and transmitted is converted into a sequence of frequency chirps. The sequence of frequencies used by the sequence of chirps is based on the symbol that is to be encoded. Each chirp can have a center frequency, and the frequency can be swept over the duration of the chirp. In this way each chirp can have a varying frequency over the duration of the chirp, but the phase of the chirp can be continuous throughout the duration of the chirp. The bandwidth and sweep rate of the chirp can be based on the expected maximum velocity of the receiver and the transmitter relative to one another.

A spread-spectrum transmitter is disclosed. The transmitter includes a modulator configured to produce an intermediate frequency signal, a frequency shifter configured to shift the intermediate frequency factor by a first factor, and a local oscillator (LO) configured to generate a LO signal. The transmitter further includes a ramp signal generator configured to determine the value of the first factor and a second factor, is configured to transmit the value of the factor to the frequency shifter, is configured to transmit the value of the second factor to the LO, where the frequency of the intermediate frequency signal shifted by the first factor is shifted synchronously with the frequency of the LO signal shifted by the second factor. The transmitter includes a mixer configured to mix the shifted intermediate frequency with the shifted LO signal that has been shifted by the second factor, producing a spread leaked LO signal.

A wireless networking system is provided. The wireless networking system includes a base station device including processing circuitry configured to detect a transmission rate from a portion of a preamble of an incoming packet transmission signal and adapt a radio configuration to receive a remainder of the incoming packet transmission signal at the transmission rate.

An optical transmission device includes: a control module generate a control signal output which includes a slope adjust signal and a bias voltage offset adjust signal according to an input signal indicating a dispersion amount an electrical level adjust signal; a multi-level pulse amplitude modulator; and an asymmetrical optical modulator which is controlled by the slope adjust signal to be operated at one of a positive slope and a negative slope of a transfer function of the asymmetrical optical modulator itself, and is controlled by the bias voltage offset adjust signal of the control signal output to offset a bias voltage point of the asymmetrical optical modulator itself from a quadrature point of the transfer function, and modulates the multi-level pulse amplitude modulation signal to an optical signal to generate an optical modulate signal having a chirp.

An optical transmission device includes: a control module generate a control signal output which includes a slope adjust signal and a bias voltage offset adjust signal according to an input signal indicating a dispersion amount an electrical level adjust signal; a multi-level pulse amplitude modulator; and an asymmetrical optical modulator which is controlled by the slope adjust signal to be operated at one of a positive slope and a negative slope of a transfer function of the asymmetrical optical modulator itself, and is controlled by the bias voltage offset adjust signal of the control signal output to offset a bias voltage point of the asymmetrical optical modulator itself from a quadrature point of the transfer function, and modulates the multi-level pulse amplitude modulation signal to an optical signal to generate an optical modulate signal having a chirp.

A controller and a method is provided for controlling a capacitance of an LC circuit having a circuit frequency including, a variable capacitor to couple with an external inductor as part of an LC circuit, a target value, a spread spectrum function to generate an adjustment value, and a circuit to poll the target value, call the spread spectrum function, and set a capacitance of the variable capacitor based on the sum of the target value and the adjustment value.