An apparatus comprising a local oscillator (LO) for driving a mixer, the LO being configured to oscillate at an oscillation frequency, and generate a first set of LO signals, wherein each of the first set of LO signals has a LO signal frequency equal to a first multiplication factor m multiplied by the oscillation frequency, the first multiplication factor m, being an integer greater than or equal to two, and each of the first set of LO signals is separated by adjacent LO signals by a phase difference equal to 360° divided by a first variable n, the first variable n being an integer that is greater than or equal to two.

An apparatus comprising a local oscillator (LO) for driving a mixer, the LO being configured to oscillate at an oscillation frequency, and generate a first set of LO signals, wherein each of the first set of LO signals has a LO signal frequency equal to a first multiplication factor m multiplied by the oscillation frequency, the first multiplication factor m, being an integer greater than or equal to two, and each of the first set of LO signals is separated by adjacent LO signals by a phase difference equal to 360° divided by a first variable n, the first variable n being an integer that is greater than or equal to two.

An RFID receiver (1) comprises an antenna (11) configured to receive a radio signal (20) from an RFID transmitter (2) and to generate an electrical signal (110) from the radio signal (20) received from the RFID transmitter (2). A decoder circuit (10) is connected to the antenna (11) and configured to extract from the electrical signal (110) generated by the antenna (11) data bits encoded in the electrical signal (110). The decoder circuit (10) comprises an analog-to-digital converter (12) connected directly to the antenna (11) and configured to generate a digital input signal (13) from the electrical signal (110) generated by the antenna (11). A bit extractor (14) is connected to the analog-to-digital converter (12) and configured to extract the data bits from the digital input (13) signal generated by the analog-to-digital converter (12).

In a communication system of the LPWAN type including a server and a plurality of gateways intended to make wireless communications with terminals in said communication system, the server: obtains a description of a mobility hierarchy in which mobility types are hierarchically defined; obtains a description of a mobility tree in which mobility areas are hierarchically defined, in conformity with the mobility hierarchy; obtains terrain measurements associated with each mobility area defined in the mobility tree; establishes a frequency plan on the basis of the mobility tree and terrain measurements; and configures the gateways and the terminals according to the frequency plan established.

In a communication system of the LPWAN type including a server and a plurality of gateways intended to make wireless communications with terminals in said communication system, the server: obtains a description of a mobility hierarchy in which mobility types are hierarchically defined; obtains a description of a mobility tree in which mobility areas are hierarchically defined, in conformity with the mobility hierarchy; obtains terrain measurements associated with each mobility area defined in the mobility tree; establishes a frequency plan on the basis of the mobility tree and terrain measurements; and configures the gateways and the terminals according to the frequency plan established.

A phase-shifter circuit arranged to receive a reference timing signal and to output a phase-shifted form of the reference timing signal. The phase-shifter circuit comprises a delay circuit arranged to receive the reference timing signal and a delay control signal, and to delay transitions within the reference timing signal to generate the phase-shifted form of the reference timing signal, wherein the amount of delay applied by the delay circuit to the transitions within the reference timing signal is controllable by the delay control signal. The phase-shifter circuit further comprises a delay control circuit arranged to receive a re-timed signal comprising transitions re-timed to transitions of the phase-shifted form of the reference timing signal output by the phase-shifter circuit, and to generate the delay control signal for the delay circuit based on the received re-timed signal.

A wireless system includes an active oscillator and a front-end circuit. The active oscillator is used to generate and output a reference clock. The active oscillator includes at least one active component, and does not include an electromechanical resonator. The front-end circuit is used to process a transmit (TX) signal or a receive (RX) signal according to a local oscillator (LO) signal. The LO signal is derived from the reference clock.

A wireless system includes an active oscillator and a front-end circuit. The active oscillator is used to generate and output a reference clock. The active oscillator includes at least one active component, and does not include an electromechanical resonator. The front-end circuit is used to process a transmit (TX) signal or a receive (RX) signal according to a local oscillator (LO) signal. The LO signal is derived from the reference clock.

The present invention brings about an effect of reducing a deterioration in communication quality that may occur in a communication circuit that can communicate in different communication modes. A communication circuit (100) of an aspect of the present invention includes a control section (109) that (i) controls a reception filter (194) such that respective passbands of a transmission filter (103) and the reception filter (104) are different from each other in a case where a full-duplex communication is made in a FDD mode, and (ii) controls the reception filter (104) such that at least part of the passband of the transmission filter (103) and at least part of the passband of the reception filter (104) overlap each other in a case where a full-duplex communication is made in a TDD mode.

A bidirectional time-division duplexing transceiver circuit includes a first and a second bidirectional phase-shift circuit, and a bidirectional amplifier circuit including a first amplifier circuit and a second amplifier circuit. The first amplifier circuit and the second amplifier circuit are coupled via double-pole-double-throw (DPDT) switches to radio-frequency (RF) antennas and the first and the second bidirectional phase-shift circuits. The (DPDT) switches enable the first amplifier circuit and the second amplifier circuit to be operable simultaneously as transmit (TX) path amplifiers in a first time slot and as a receive (RX) path amplifiers in a second time slot.