A demodulator for pulse-width modulated clock signals is disclosed. In one aspect, the demodulator includes an edge detector configured to detect transitions in a reference clock and output a signal indicative of timing of the detected transitions. The demodulator may also include a modulation detection circuit configured to identify modulation events of at least one pulse-width modulated pulse in the reference clock based on the signal output from the edge detector and output a signal indicative of the at least one pulse-width modulated pulse modulation event being identified. The demodulator may further include a retiming circuit configured to generate an output clock synchronized with the at least one pulse-width modulated pulse modulation event based on the signal output from the modulation detection circuit.

Methods, systems, and apparatus for EM communications. One of the apparatus includes a super-regenerative amplifier (SRA) configured to receive a binary phase shift keying (BPSK) modulated signal and to output an amplitude signal as a function of changes in phase in the BPSK modulated signal; a pseudo synchronous demodulator that rectifies the amplitude signal and generates an envelope of the rectified amplitude signal; and an analog to digital converter that converts the amplitude values of the envelope to digital binary values.

Systems and methods for improved digital RF transport in a DAS are provided. In one embodiment, a transceiver comprises: a receive path circuit including an RF reception interface coupled to an ADC, the ADC receiving a down-converted analog RF spectrum from the RF reception interface and producing a digitized RF spectrum at an input sampling rate; a logic device receiving the digitized RF spectrum and producing a first set of baseband data samples at a first sampling rate, corresponding to a first spectral region of the analog RF spectrum and a second set of baseband data samples at a second sampling rate, corresponding to a second spectral region of the analog RF spectrum. The logic device maps the first set and second sets of baseband data samples to a respective first set and second set of timeslots of a serial data stream transport frame.

Circuits and methods for reducing the cost and/or power consumption of a user terminal and/or the gateway of a telecommunications system (550) that may include a telecommunications satellite. Embodiments generate a dynamic input bias signal based upon an information signal envelope (which may be pre-distorted) which is applied to the signal input of a power amplifier (PA), thus reducing average power consumption. Other embodiments further include dynamic linearization (518) of the information signal, and/or variation of the supply voltage to the power amplifier (PA) as a function of the envelope of the information signal. Another aspect is a multi-stage chained feedback regulated voltage supply circuit for providing two or more output voltages that may be used as alternative supply voltages to a power amplifier (PA).

Methods and systems for waking up a wireless receiving device having a wake-up radio (WUR) circuit. A low-power wake-up signal is transmitted, comprising a wake-up frame (WUF) including having a portion that is subjected to spectrum spreading and transmitted using a single carrier. The wake-up signal is processed by the receiving using non-coherent detection.

Methods and systems for waking up a wireless receiving device having a wake-up radio (WUR) circuit. A low-power wake-up signal is transmitted, comprising a wake-up frame (WUF) including having a portion that is subjected to spectrum spreading and transmitted using a single carrier. The wake-up signal is processed by the receiving using non-coherent detection.

A physiological information collecting system and a transceiver device thereof are configured to collect physiological information from animal bodies. The transceiver device includes a front-end circuit, a follower circuit, a quadrature delay line and an output circuit. The front-end circuit separates a discontinuous signal into an in-phase signal and a quadrature signal. The follower circuit outputs a control voltage and rotates the in-phase signal by a predetermined phase angle to output a follower signal. The quadrature delay line rotates the quadrature signal by a corresponding phase angle according to the control voltage. The output circuit synthesizes the follower signal and the quadrature signal and outputs a data signal by demodulating the discontinuous signal. Consequently, the transceiver device reduces the bandwidth range of the discontinuous signal when receiving the discontinuous signal, reduces the power consumed by the transceiver device, and demodulates the discontinuous signal with various transmission rates of different data.

A method is disclosed of generating a frequency shift keying (FSK) signal comprised in an orthogonal frequency division multiplexing (OFDM) signal comprising a plurality of sub-carriers. The FSK signal comprises FSK symbols wherein each FSK symbol has a corresponding FSK symbol frequency. The method comprises assigning a set of adjacent sub-carriers to transmission of the FSK signal (wherein the set is a sub-set of the plurality of sub-carriers), and associating each FSK symbol frequency with a corresponding sub-carrier in the set of adjacent sub-carriers. The method also comprises selecting, for each FSK symbol to be transmitted, an FSK symbol phase such that an FSK signal phase at a start of the FSK symbol to be transmitted meets a phase difference criterion in relation to the FSK signal phase at an end of an immediately previous FSK symbol. The method further comprises generating the FSK signal comprising the FSK symbol to be transmitted by modulating the sub-carrier corresponding to the FSK symbol frequency based on the selected FSK symbol phase and muting the remaining sub-carriers of the set. Corresponding arrangement, access point and computer program product are also disclosed.

A user equipment (910) is provided for use in a cellular network. The user equipment includes a transceiver (1010), a processor (1020), and a memory (1030). The user equipment (910 is configured to determine, for a data transmission a mapping form a demodulation reference signal (DMRS) to a PNT-RS. A DMRS resulting signal is generated from a subset of DMRS for a first resource element in a subcarrier. The DMRS resulting signal is copied from the first resource element to a second resource element assigned to the PNT-RS in the subcarrier. The data transmission is transmitted using the DMRS resulting signal and the PNT-RS.

The present invention discloses a real-time normalization apparatus and method of the PGC demodulation in a sinusoidal phase modulation interferometer. An optical setup containing a measuring interferometer and a monitoring interferometer is constructed. An electro-optic phase modulator is placed in the common reference arm of the two interferometers. High-frequency sinusoidal wave modulation and low-frequency triangular wave modulation are applied to the electro-optic phase modulator at the same time. Sinusoidal modulation is used for generating phase carrier, and PGC demodulation is performed to obtain quadrature signals containing the phase information to be measured. Triangular wave modulation makes the quadrature signals change periodically. Ellipse fitting is performed on the Lissajous figure corresponding to the quadrature signals, and real-time normalization of the PGC demodulated quadrature signals is achieved. By calculating the variation of the phase difference between the two interference signals, the measured displacement is obtained, and nanometer scale displacement measurement is achieved.