A transmitter for use in a communication system uses a orthogonal modulation method, and the transmitter includes: an orthogonal sequence prescriber that prescribes association between orthogonal signals and information words determined on the basis of sizes of differences between information words of a plurality of mutually different information words and a probability of occurrence of decision errors between orthogonal signals of a plurality of mutually orthogonal signals; and a symbol mapper that, upon input of any of the information words, generates modulation symbols based on the orthogonal signals associated with the input information word according to the associations prescribed by the orthogonal sequence prescriber.

A digital frequency modulation receiver includes a phase capturer, an adder, a digital filter and a phase estimator. The phase estimator is used to generate a first phase value according to an input signal. The adder is coupled to the phase estimator for subtracting a second phase value from the first phase value to generate a phase difference. The digital filter is coupled to the adder for performing a filtering calculation with the phase difference so as to generate a frequency variation signal. The phase estimator is coupled to the digital filter and the adder so as to update the second phase value according to the frequency variation signal.

A radio frequency (RF) front end chip in a phased array antenna panel for transmitting a modulated circularly-polarized signal is disclosed. The RF front end chip includes an oscillator providing an angular speed modulation signal to a quadrature generation block, the quadrature generation block providing an in-phase signal and a quadrature signal based on the angular speed modulation signal, a first amplifier receiving the in-phase signal and a data signal, and providing a modulated horizontally-polarized signal, and a second amplifier receiving the quadrature signal and the data signal, and providing a modulated vertically-polarized signal, where a modulated circularly-polarized signal is generated based on the modulated horizontally-polarized signal and the modulated vertically-polarized signal. The angular speed modulation signal controls an angular speed of the modulated circularly-polarized signal. The data signal is encoded by the angular speed modulation signal.

A system for bidirectional transmission in a plastic waveguide of a plurality of signals, between a first transceiver device and a second transceiver device, the plurality of signals comprising a payload carrier signal and one or more reference signals generated by one or more local oscillators on different frequencies, the first transceiver device being a power radio transceiver device, the second transceiver device being a multisignal transceiver device with no energy consumption which comprises a passive transmitter and a passive receiver.

A system for bidirectional transmission in a plastic waveguide of a plurality of signals, between a first transceiver device and a second transceiver device, the plurality of signals comprising a payload carrier signal and one or more reference signals generated by one or more local oscillators on different frequencies, the first transceiver device being a power radio transceiver device, the second transceiver device being a multisignal transceiver device with no energy consumption which comprises a passive transmitter and a passive receiver.

An ultra-wideband radio frequency transmission system capable of receiving a first signal with discrete levels, and including: a voltage-controlled oscillator capable of supplying a first oscillating signal including an oscillating circuit powered by a power supply circuit comprising at least one first current source controlled by the first signal with discrete levels or a second signal with discrete levels obtained from the first signal with discrete levels; a mixer capable of receiving the first oscillating signal and of supplying a second oscillating signal equal to the first oscillating signal multiplied by a gain which depends on the first signal with discrete levels or on a third signal with discrete levels obtained from the first signal with discrete levels; and an antenna or an electromagnetic coupling device capable of transmitting a radio frequency signal based on the second oscillating signal.

Apparatus and methods for disrupting or preventing periodicity in DTC circuits are provided. In an example, a communication circuit can include a digital-to-time converter (DTC) and a processing path coupled to the DTC. The DTC can be configured to receive reference information, modulation information and first dither information, and to provide a modulated signal using the reference information, the modulation information and the first dither information. The processing path can be configured to receive second dither information and to cancel the first dither information using the second dither information, wherein the DTC is configured to disrupt processing periodicity of the communication circuit using the first dither information.

A radio transmission method which includes a steps of simulation of a phase modulation of a radio carrier by the successive transmission of a carrier of a main frequency f and of a carrier of an offset frequency f+Δf, the offset frequency having a frequency difference suitable for simulating a given phase shift of the main frequency at the end of a given time T. The invention further relates to a radio transmission device for implementing the method which includes a radio integrated circuit for generating programmable frequency modulation, means for programming, in this radio integrated circuit, the main frequency f and the offset frequency f+Δf and means for driving this radio integrated circuit in order to generate the frequencies as a function of the signal to be transmitted.

A voltage controlled oscillator includes a first inductor; a first variable capacitance unit including a first variable capacitance element having a variable capacitance and a second variable capacitance element having a variable capacitance; a first node configured for application of a first voltage to the first variable capacitance unit; a cross-coupled unit including a first transistor and a second transistor, an output of the first transistor connected to an input of the second transistor; a current source configured to flow a current through the first inductor, the first transistor, and the second transistor; a second variable capacitance unit including a third variable capacitance element having a variable capacitance, and a fourth variable capacitance element having a variable capacitance; and a second node different from the first node configured for application of a second voltage to the second variable capacitance unit.

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.