METHOD AND APPARATUS FOR DETERMINING LOCATION USING PHASE DIFFERENCE OF ARRIVAL

• US 20190331783A1
• Filed: 03/13/2019
• Published: 10/31/2019
• Est. Priority Date: 04/26/2018
• Status: Active Grant

• Current Assignee: DecaWave Limited (Qorvo, Inc.)
• Original Assignee: DecaWave Limited (Qorvo, Inc.)
• Inventors: McLaughlin, Michael, Marrow, Gavin, Dotlic, Igor
• Granted Patent: US 11,215,704 B2
• Time in Patent Office: Days
• CPC Class Codes: G01S 13/0209 Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband
• CPC Class Codes: G01S 3/023 Monitoring or calibrating
• CPC Class Codes: G01S 3/48 the waves arriving at the antennas being continuous or intermittent and the phase difference of signals derived therefrom being measured
• CPC Class Codes: G01S 5/06 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/12 takes precedence

Abstract

An ultra-wideband (“UWB”) communication system comprising a transmitter and a receiver having two antennas. An UWB signal transmitted by the transmitter is received at each of the antennas. By comparing the carrier phases of the received signals, the phase difference can be determined. From this phase difference and the known distance, d, between the antennas, the Cartesian (x, y) location of the transmitter relative to the receiver can be directly determined.

Claims

1. In an ultra-wideband (UWB) system comprising a UWB transmitter adapted to transmit a first signal in a first channel and a second signal in a second channel different from the first channel, and a UWB receiver having first and second antennae separated by a first distance, d, a method comprising the steps of:

1.1 using the first antenna to receive the first transmitted signal;

1.2 using the second antenna to receive the transmitted first signal;

1.3 using the receiver to;

1.3.1 develop a first range, r₁, between the transmitter and a selected one the first and second antennas;

1.3.2 develop a first phase value as a function of the complex baseband impulse response of the first transmitted signal received by the first antenna;

1.3.3 develop a second phase value as a function of the complex baseband impulse response of the first transmitted signal received by the second antenna;

1.3.4 develop a first path difference value, p₁, as a function of the first and second phase values;

1.4 using the first antenna to receive the second transmitted signal;

1.5 using the second antenna to receive the second transmitted signal;

1.6 using the receiver to;

1.6.1 develop a second range, r₂, between the transmitter and a selected one the first and second antennas;

1.6.2 develop a third phase value as a function of the complex baseband impulse response of the second transmitted signal received by the first antenna;

1.6.3 develop a fourth phase value as a function of the complex baseband impulse response of the second transmitted signal received by the second antenna;

1.6.4 develop a second path difference value, p₂, as a function of the third and fourth phase values; and

1.6.5 develop an (x,y) location of the transmitter relative to the receiver as a function of d, r₁, p₁, r₂, and p₂.

2. The method of claim 1 wherein d is greater than one half a wavelength λ

₁, of the first signal, and greater than one half a wavelength, λ

₂, of the second signal.

3. The method of claim 1 wherein step 1.3.4 is further characterized as:

1.3.4 develop the first path difference value, p₁, as a function of the first and second phase values and of a selected first calibration function; and

wherein step 1.6.4 is further characterized as;

1.6.4 develop a second path difference value, p₂, as a function of the third and fourth phase values and of the selected second calibration function.

4. A location determination circuit configured to perform the method of claim 1.

5. An RF receiver comprising a location determination circuit according to claim 4.

6. An RF transceiver comprising a wireless receiver according to claim 5.

7. An RF communication system comprising a wireless transceiver according to claim 6.

8. A non-transitory computer readable medium including executable instructions which, when executed in an RF system, causes the system to perform the steps of a method according to claim 1.