US 12,192,951 B2 · Synchronization of receiver and transmitter local oscillators for ranging applications

Abstract

A system and method for accurately determining a distance between two network devices using a Channel Sounding application is disclosed. The network devices each guarantee a fixed phase relationship between the transmit circuit and the receive circuit. In one embodiment, this is achieved by disposing the divider outside the phase locked loop and using the output of the divider to create the clocks for both the transmit circuit and receive circuit. In another embodiment, one or more dividers are disposed outside the phase locked loop, each having a reset, such that they can be initialized to a predetermined state. Further, by utilizing a divider with a reset, the quadrature signal generator is guaranteed to output clocks for the transmit circuit and the receive circuit that have a constant phase relationship.

Claims20

Dependent claims

A method of performing a distance measurement between a first network device and a second network device, comprising:

transmitting a first packet from the first network device to the second network device, using a first frequency;
replying to the first packet by transmitting a second packet from the second network device to the first network device using the first frequency;
transmitting a third packet from the first network device to the second network device using a second frequency, different from the first frequency;
replying to the third packet by transmitting a fourth packet from the second network device to the first network device using the second frequency;
and
calculating a distance based on a phase received by the first network device and the second network device for each packet, the first frequency and the second frequency,
wherein the first network device and the second network device each comprise a clock generation circuit having a phase locked loop and one divider disposed outside the phase locked loop to generate a receive clock and a transmit clock, such that a phase difference between the transmit clock and the receive clock of each network device is constant.

4 more elements

A method of performing a distance measurement between a first network device and a second network device, comprising:

transmitting a first packet from the first network device to the second network device, using a first frequency;
replying to the first packet by transmitting a second packet from the second network device to the first network device using the first frequency;
transmitting a third packet from the first network device to the second network device using a second frequency, different from the first frequency;
replying to the third packet by transmitting a fourth packet from the second network device to the first network device using the second frequency;
and
calculating a distance based on a phase received by the first network device and the second network device for each packet, the first frequency and the second frequency,
wherein the first network device and the second network device comprises a clock generation circuit having a phase locked loop and two dividers disposed outside the phase locked loop to generate a receive clock and a transmit clock, such that a phase difference between the transmit clock and the receive clock of each network device is constant.

4 more elements

Dependencies are inferred from the claim text.

Synchronization of receiver and transmitter local oscillators for ranging applications

Life of this patent

Synchronization of receiver and transmitter local oscillators for ranging applications

Life of this patent

Abstract

Claims20