A gateway device having a baseband processor for processing a plurality signals carrying a digital information modulated in the form of chirp signal, the chirp signals being either base chirps, for which the frequency changes from an initial instant to a final instant according to a predetermined base chirp function or modulated chirps, whose instantaneous frequencies vary according to one of a plurality of a functions that differ from said base chirp function, characterized in that the gateway device is arranged for simultaneously demodulating a plurality of signals having received at a same frequency and exhibiting different bitrates.

A dual decoder for a wireless charging receiver and a wireless charging receiver using the same are provided. The wireless charging receiver includes a resonant circuit, a rectifier circuit and a dual decoder for the wireless charging receiver. The rectifier circuit coupled to the resonant circuit converts wireless energy received by the resonant circuit into a direct current. The dual decoder includes a frequency decoding circuit and a voltage amplitude decoding circuit. The frequency decoding circuit performs decoding according to a frequency of a voltage of the resonant circuit to obtain an instruction of a wireless transmitter. The voltage amplitude decoding circuit extracts a carrier on the voltage of the resonant circuit through a filter, and decodes the carrier into the instruction of the wireless transmitter. With the complementary of two-way decoding, the communication system becomes robuster.

A method and apparatus for identifying a search window of carrier-frequency-offset-corrected samples in which a first intermediate signal from a demodulator does not exceed a predetermined threshold, convolving a second intermediate signal from the demodulator within the search window with a predefined pattern to provide a convolution result, determining if an absolute peak of the convolution result exceeds a preamble pattern confirmation threshold, in response to the absolute peak of the convolution result exceeding the preamble confirmation threshold, confirming a preamble pattern detection event to provide a confirmed preamble pattern detection event of a confirmed preamble pattern, and receiving a signal including the confirmed preamble pattern to provide a received digital signal extracted from the signal.

A method and apparatus for identifying a search window of carrier-frequency-offset-corrected samples in which a first intermediate signal from a demodulator does not exceed a predetermined threshold, convolving a second intermediate signal from the demodulator within the search window with a predefined pattern to provide a convolution result, determining if an absolute peak of the convolution result exceeds a preamble pattern confirmation threshold, in response to the absolute peak of the convolution result exceeding the preamble confirmation threshold, confirming a preamble pattern detection event to provide a confirmed preamble pattern detection event of a confirmed preamble pattern, and receiving a signal including the confirmed preamble pattern to provide a received digital signal extracted from the signal.

Systems and methods for transpositional modulation and demodulation are provided. One such method for generating a signal includes the steps of providing a look-up table having a plurality of quarter-cycle waveforms, each of said quarter-cycle waveforms associated with a respective input level; receiving an input signal; and outputting quarter-cycle waveforms associated with levels of the received input signal. Systems for transpositional modulation are also provided. One such system for generating a signal includes a look-up table having a plurality of quarter-cycle waveforms. Each of the quarter-cycle waveforms are associated with a respective input level, and the look-up table is configured to receive an input signal, and output quarter-cycle waveforms associated with levels of the received input signal.

Systems and methods for transpositional modulation and demodulation are provided. One such method for generating a signal includes the steps of providing a look-up table having a plurality of quarter-cycle waveforms, each of said quarter-cycle waveforms associated with a respective input level; receiving an input signal; and outputting quarter-cycle waveforms associated with levels of the received input signal. Systems for transpositional modulation are also provided. One such system for generating a signal includes a look-up table having a plurality of quarter-cycle waveforms. Each of the quarter-cycle waveforms are associated with a respective input level, and the look-up table is configured to receive an input signal, and output quarter-cycle waveforms associated with levels of the received input signal.

In at least one embodiment of the invention, a method for reducing a dynamic range of a received radio frequency signal includes receiving digital IQ signals corresponding to an in-phase component of the received radio frequency signal and a quadrature component of the received radio frequency signal. The method includes demodulating the digital IQ signals to generate an instantaneous frequency signal. The method includes selecting a center frequency of a selectable filter according to whether an interfering signal is detected in a target frequency band of the received radio frequency signal. The center frequency is selected from a predetermined frequency and an estimated center frequency determined using the instantaneous frequency signal. The method includes filtering the digital IQ signals using the selectable filter configured using the center frequency to generate output digital IQ signals.

In at least one embodiment of the invention, a method for reducing a dynamic range of a received radio frequency signal includes receiving digital IQ signals corresponding to an in-phase component of the received radio frequency signal and a quadrature component of the received radio frequency signal. The method includes demodulating the digital IQ signals to generate an instantaneous frequency signal. The method includes selecting a center frequency of a selectable filter according to whether an interfering signal is detected in a target frequency band of the received radio frequency signal. The center frequency is selected from a predetermined frequency and an estimated center frequency determined using the instantaneous frequency signal. The method includes filtering the digital IQ signals using the selectable filter configured using the center frequency to generate output digital IQ signals.

In one example, an apparatus includes: a delay unit to delay a demodulated signal obtained from an input radio frequency (RF) frequency modulation (FM) signal; a filter to filter the demodulated signal and output a filtered demodulated signal; an impulse detection circuit to receive the filtered demodulated signal and detect presence of an impulse in the demodulated signal; and an impulse removal circuit to remove the detected impulse from the demodulated signal.

In one example, an apparatus includes: a delay unit to delay a demodulated signal obtained from an input radio frequency (RF) frequency modulation (FM) signal; a filter to filter the demodulated signal and output a filtered demodulated signal; an impulse detection circuit to receive the filtered demodulated signal and detect presence of an impulse in the demodulated signal; and an impulse removal circuit to remove the detected impulse from the demodulated signal.