A method of demodulating an FSK modulated input signal whose frequency varies between first and second frequencies. The input signal is delayed by a plurality of cycles, providing a second signal. A succession of phase reference signals having respective incrementally greater phase delays relative to the input signal are provided. Samples of the phase reference signals are taken at intervals determined by the second signal. A transition between the first and second frequencies is detected when the relative values of the samples of the phase reference signals remain constant during a plurality of intervals after varying. A high speed clock is not required to perform the demodulation.

A receiver may receive a pulse width encoded signal. The receiver may determine a position of a transition of a pulse of the pulse width encoded signal by oversampling the pulse width encoded signal with respect to a quantization function. The receiver may determine that the position of the transition deviates from an expected position according to the quantization function by more than a predetermined range. The receiver may generate a signal, indicating an unexpected event, based on determining that the position of the transition deviates from the expected position. The receiver may detect an error in a message corresponding to the pulse width encoded signal based on a check value identified from the pulse width encoded signal. The receiver may adjust, based on the signal indicating the unexpected event, a value, corresponding to the position of the transition, to cause the error in the message to be corrected.

A method of transmitting a Physical Layer Convergence Procedure (PLCP) frame in a Very High Throughput (VHT) Wireless Local Area Network (WLAN) system includes generating a MAC Protocol Data Unit (MPDU) to be transmitted to a destination station (STA), generating a PLCP Protocol Data Unit (PPDU) by adding a PLCP header, including an L-SIG field containing control information for a legacy STA and a VHT-SIG field containing control information for a VHT STA, to the MPDU, and transmitting the PPDU to the destination STA. A constellation applied to some of Orthogonal Frequency Division Multiplex (OFDM) symbols of the VHT-SIG field is obtained by rotating a constellation applied to an OFDM symbol of the L-SIGfield.

A method of operation of a wireless charger device includes transmitting a wireless charging signal to a receiver device. The method further includes receiving a clamping pulse from the receiver device based on the wireless charging signal. The clamping pulse indicates a first value associated with a falling edge of the clamping pulse and further indicates a second value associated with a rising edge of the clamping pulse. The clamping pulse is detected based on a comparison of a first threshold with the first value and further based on a comparison of a second threshold with the second value, and the second threshold is different than the first threshold. The method further includes determining a charging state of the receiver device based on the clamping pulse.