Communication systems and methods in accordance with various embodiments of the invention utilize modulation on zeros. Carrier frequency offsets (CFO) can result in an unknown rotation of all zeros of a received signal's z-transform. Therefore, a binary MOCZ scheme (BMOCZ) can be utilized in which the modulated binary data is encoded using a cycling register code (e.g. CPC or ACPC), enabling receivers to determine cyclic shifts in the BMOCZ symbol resulting from a CFO. Receivers in accordance with several embodiments of the invention include decoders capable of decoding information bits from received discrete-time baseband signals by: estimating a timing offset for the received signal; determining a plurality of zeros of a z-transform of the received symbol; identifying zeros from. the plurality of zeros that encode received bits by correcting fractional rotations resulting from the CFO; and decoding information bits based upon the received bits using a cycling register code.

Systems and apparatuses for wireless power transfer system are described. A receiver may send an amplitude shift key (ASK) signal to a transmitter. The transmitter may receive the ASK signal from the receiver. The transmitter may perform a demodulation on the ASK signal. The transmitter may, in response to a failure to demodulate the ASK signal, encode a notification of failure in a frequency shift key (FSK) signal. The transmitter may transmit the FSK signal to the receiver. The receiver may receive the FSK signal. The receiver may perform a function to resolve the failure to demodulate the ASK signal.

Systems and apparatuses for wireless power transfer system are described. A receiver may send an amplitude shift key (ASK) signal to a transmitter. The transmitter may receive the ASK signal from the receiver. The transmitter may perform a demodulation on the ASK signal. The transmitter may, in response to a failure to demodulate the ASK signal, encode a notification of failure in a frequency shift key (FSK) signal. The transmitter may transmit the FSK signal to the receiver. The receiver may receive the FSK signal. The receiver may perform a function to resolve the failure to demodulate the ASK signal.

A radio frequency (RF) aperture includes an array of electrically conductive tapered projections arranged to define a curved aperture surface, such as a semi-cylinder aperture surface, or a cylinder aperture surface (which may be constructed as two semi-circular aperture surfaces mutually arranged to define the cylinder aperture surface). The RF aperture may further include a top array of electrically conductive tapered projections arranged to define a top aperture surface. The top aperture surface may be planar, and a cylinder axis of cylinder aperture surface may be perpendicular to the plane of the planar top aperture surface. The RF aperture may further include baluns mounted on at least one printed circuit board, each having a balanced port electrically connected with two neighboring electrically conductive tapered projections of the array and further having an unbalanced port.

The invention discloses a modulator, a demodulator and a wireless communication system. The wireless communication system comprises a modulator and a demodulator. The modulator is suitable for generating a target linear frequency modulation signal, wherein the target linear frequency modulation signal is a signal of which the frequency is varied linearly over time, wherein the phase of the target linear frequency modulation signal is determined by an initial frequency and a frequency stepping of the target linear frequency modulation signal, and the frequency stepping is determined by the bandwidth of the target linear frequency modulation signal and the spreading factor of the target linear frequency modulation signal. The demodulator is suitable for demodulating the target linear frequency modulation signal. According to the scheme, power consumption can be reduced while long-distance signal transmission is realized.

A system comprising a relay device that configures to a first beamforming setting for a first set of antenna arrays to establish a first link between the relay device and a source device, and a second beamforming setting to establish a second link between the relay device and a destination device. A data stream is processed based on a selection of one of a passive mode or an active mode of relay operation. In the passive mode, a received radio frequency waveform of the data stream is down-converted to an intermediate frequency waveform, re-amplified, and then up-converted for transmission without requiring any data demodulation, and in the active mode, the IF waveform is demodulated and then remodulated for the transmission. The data stream is forwarded to the destination device through the second link based on the selection of one of the passive or active mode.

A system comprising a relay device that configures to a first beamforming setting for a first set of antenna arrays to establish a first link between the relay device and a source device, and a second beamforming setting to establish a second link between the relay device and a destination device. A data stream is processed based on a selection of one of a passive mode or an active mode of relay operation. In the passive mode, a received radio frequency waveform of the data stream is down-converted to an intermediate frequency waveform, re-amplified, and then up-converted for transmission without requiring any data demodulation, and in the active mode, the IF waveform is demodulated and then remodulated for the transmission. The data stream is forwarded to the destination device through the second link based on the selection of one of the passive or active mode.

A signal generation method is used in a transmission device that transmits a plurality of transmission signals from a plurality of antennas at the same frequency and at the same time, in the case where larger power change is performed on a first transmission signal than on a second transmission signal during generation process of the first transmission signal and the second transmission signal, the first transmission signal and the second transmission signal are mapped before the power change such that a minimum Euclidian distance between possible signal points for the first signal is longer than a minimum Euclidian distance between possible signal points for the second signal.

A signal generation method is used in a transmission device that transmits a plurality of transmission signals from a plurality of antennas at the same frequency and at the same time, in the case where larger power change is performed on a first transmission signal than on a second transmission signal during generation process of the first transmission signal and the second transmission signal, the first transmission signal and the second transmission signal are mapped before the power change such that a minimum Euclidian distance between possible signal points for the first signal is longer than a minimum Euclidian distance between possible signal points for the second signal.

An oscillator drive circuit and a trim circuit are implemented inside an integrated circuit of a sensor. The drive circuit provides an oscillating drive signal at a resonant frequency to drive a movable mass of the sensor. The drive circuit includes a phase shift circuit having an input for receiving a first signal indicative of an oscillation of the movable mass and having an output. The phase shift circuit adds a phase shift component to the first signal and produces a second signal shifted in phase by the phase shift component. The trim circuit includes a first comparator for receiving the first signal, a second comparator for receiving the second signal, and a processing element. The processing element determines a phase lag between the first and second signals and produces trim code for use by the phase shift circuit, the trim code being configured to adjust the phase shift component.