Abstract: Radio transceiver device and method are provided. The method includes sequentially transmitting radio frequency signals on radio channels, each channel being nonuniformly spaced and representing a distinct continuous tone, sequentially transmitting radio frequency signals with distinct continuous tones on same channels as those received from the first radio transceiver device, as well as measured phase difference of the radio frequency signals on each radio channel received from the first radio transceiver device, creating a first set of estimate candidates, repeatedly for the radio channels, determining an optimal phase unwrapping vector candidate based on the first set of estimate candidates and the measured phase differences of signals received on the first and second transceiver devices to determine a second set of candidates, and calculating the distance between the first and second radio transceiver devices using the optimal phase unwrapping vector candidate and the second set.

Abstract: A method and device for phase-based ranging measurement between a first radio frequency transceiver and a second radio frequency transceiver.

Abstract: A method for controlled phase adjustment and coherent modulation in a radio frequency transceiver is provided. The radio frequency transceiver comprises an analogue circuitry for transmitting and receiving radio frequency signals and an all-digital phase locked loop controlled by a Phase Locked Loop, PLL, Control unit (200). The method comprises: receiving a phase shift, and based thereon, deriving a corresponding digital control signal; inputting the digital control signal to the PLL Control unit (200), the control signal defining a temporary iteration pattern of delays to be used by a configurable delay block, DTC (240); locking a radio frequency oscillator signal of a Digital Controlled Oscillator (220) in the phase locked loop to the temporary iteration pattern of delays; adjusting the phase of the frequency signal in digital circuitry, until the signal phase matches the phase shift defined by the digital control signal.

Abstract: A radio system comprises a radio transmitter apparatus and a radio receiver apparatus. The radio transmitter apparatus is configured to transmit a continuous-wave radio-frequency signal having a first frequency. The radio receiver apparatus comprises: an antenna for receiving the continuous-wave radio-frequency signal; a local oscillator for generating a periodic signal at a second frequency which differs from the first frequency by a frequency offset; a mixer for mixing the received continuous-wave radio-frequency signal with the periodic signal to generate a down-mixed signal; and a processor or other circuitry configured to generate frequency-offset data from the down-mixed signal, wherein the frequency-offset data is representative of an estimate of the frequency offset. The processor or other circuitry is configured to use the frequency-offset data to generate DC-offset data representative of an estimate of a DC offset component of the down-mixed signal.

Abstract: A method of determining a distance between a radio frequency device and a target is disclosed in which the radio frequency device receives a radio frequency signal from the target. The method comprises determining a time domain channel response from the received radio frequency signal, determining an amplitude of a largest peak in the time domain channel response, determining an amplitude of a second, earlier, peak in the time domain channel response, comparing the second peak amplitude to a threshold based on the largest peak amplitude, identifying the largest peak as a shortest path peak if the second peak amplitude is less than the threshold, identifying the second peak as a shortest path peak if the second peak amplitude is greater than the threshold, and calculating the distance between the radio frequency device and the target based on a time corresponding to the shortest path peak.

Abstract: A radio system comprises a radio transmitter apparatus and a radio receiver apparatus. The radio transmitter apparatus is configured to transmit a continuous-wave radio-frequency signal having a first frequency. The radio receiver apparatus comprises: an antenna for receiving the continuous-wave radio-frequency signal; a local oscillator for generating a periodic signal at a second frequency which differs from the first frequency by a frequency offset; a mixer for mixing the received continuous-wave radio-frequency signal with the periodic signal to generate a down-mixed signal; and a processor or other circuitry configured to generate frequency-offset data from the down-mixed signal, wherein the frequency-offset data is representative of an estimate of the frequency offset. The processor or other circuitry is configured to use the frequency-offset data to generate DC-offset data representative of an estimate of a DC offset component of the down-mixed signal.

Abstract: A method for analyzing a frequency stability of a radio transceiver device comprises receiving a first succession of unmodulated radio-frequency signals of different frequencies from a radio transceiver apparatus. For each unmodulated radio-frequency signal, a respective time series of phase-offset values is determined, each phase-offset value being representative of a difference between a phase of the respective received unmodulated radio-frequency signal and a phase of a respective reference signal. The time series of phase-offset values is processed to determine a respective signal-phase-offset value for each unmodulated radio-frequency signal. A frequency-stability value, representative of a frequency stability of the radio transceiver apparatus, is calculated as a function representative of statistical variation in the signal-phase-offset values determined for the first succession of unmodulated radio-frequency signals.

Abstract: A method of determining a distance between a radio frequency device and a target is disclosed in which the radio frequency device receives a radio frequency signal from the target. The method comprises determining a time domain channel response from the received radio frequency signal, determining an amplitude of a largest peak in the time domain channel response, determining an amplitude of a second, earlier, peak in the time domain channel response, comparing the second peak amplitude to a threshold based on the largest peak amplitude, identifying the largest peak as a shortest path peak if the second peak amplitude is less than the threshold, identifying the second peak as a shortest path peak if the second peak amplitude is greater than the threshold, and calculating the distance between the radio frequency device and the target based on a time corresponding to the shortest path peak.