# US 10,871,457 B2 · Determining material category based on the polarization of received signals

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,871,457 B2
- Document ID: US10871457B2
- Status: Granted
- Kind: B2
- Application number: 16/116,486
- Filed: 2018-08-29
- Published: 2020-03-05
- Granted: 2020-12-22
- Earliest claimed: 2018-08-29
- Assignees: Honeywell International Inc.
- Applicants: Honeywell International Inc.
- Inventors: David C. Vacanti; Marc M. Pos
- Web page: https://patentgrep.com/patent/US10871457B2

## CPC

- G01N 22/00: Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more (G01N3/00 - G01N17/00, G01N24/00 take precedence)
- G01S 7/026: {involving the transmission of elliptically or circularly polarised waves}
- G01S 7/062: {in which different colours are used}
- G01S 7/411: {Identification of targets based on measurements of radar reflectivity (G01S7/415 takes precedence)}
- G01S 7/032: {Constructional details for solid-state radar subsystems}
- G01S 13/34: using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
- G01S 13/931: of land vehicles
- G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q)
- G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES

## Abstract

In some examples, a radar device is configured to detect an object, where the radar device includes transceiver circuitry configured to transmit radar signals having a first polarization type towards the object, receive radar signals having the first polarization type reflected from the object, and receive radar signals having a second polarization type reflected from the object, the second polarization type being different than the first polarization type. The radar device also includes processing circuitry configured to determine a material category of the object based on the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object.

## Claims

### Claim 1

A radar device configured to detect an object, the radar device comprising:
transceiver circuitry configured to transmit radar signals having a first polarization type towards the object, wherein the transceiver circuitry includes an antenna array configured to:
receive radar signals having the first polarization type reflected from the object; and
receive radar signals having a second polarization type reflected from the object, the second polarization type being different than the first polarization type; and
processing circuitry configured to:
interleave a first operating mode and a second operating mode;
determine reflectivity values for the radar signals having the first polarization type reflected from the object in the first operating mode;
determine reflectivity values for the radar signals having the second polarization type reflected from the object in the second operating mode; and
determine a material category of the object based on the reflectivity values for the radar signals having the first polarization type reflected from the object and the reflectivity values for the radar signals having the second polarization type reflected from the object.

### Claim 2 (depends on 1)

The radar device of claim 1, wherein the processing circuitry is configured to determine the material category at least in part by selecting the material category from a set of material categories including a conductive surface, vegetation, and a human.

### Claim 3 (depends on 1)

The radar device of claim 1,
wherein the processing circuitry is further configured to determine a power ratio of the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object, and
wherein the processing circuitry is configured to determine the material category of the object based on the power ratio.

### Claim 4 (depends on 3)

The radar device of claim 3, wherein the processing circuitry is configured to determine the material category of the object at least in part by:
determining a conductive material category for the object in response to determining that the power ratio of the radar signals exceeds a first threshold ratio; and
determining an insulative material category for the object in response to determining that the power ratio of the radar signals does is less than a second threshold ratio.

### Claim 5 (depends on 3)

The radar device of claim 3, wherein the processing circuitry is further configured to associate a set of voxels with the object based on a power ratio of radar signals reflected from the set of voxels and further based on a Bayesian classifier algorithm.

### Claim 6 (depends on 1)

The radar device of claim 1,
wherein the processing circuitry is further configured to determine a phase relationship between the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object, and
wherein the processing circuitry is configured to determine the material category of the object based on the phase relationship.

### Claim 7 (depends on 1)

The radar device of claim 1, wherein the processing circuitry is configured to determine the material category of the object based on an algorithm including, as input variables:
a power ratio of the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object; and
a phase relationship between the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object.

### Claim 8 (depends on 1)

The radar device of claim 1, wherein the antenna array comprises a second array of patch elements, and wherein the transceiver circuitry comprises:
a circuit board;
transmit circuitry including a first array of patch elements integrated into the circuit board and configured to transmit the radar signals having the first polarization type; and
receiver circuitry including the second array of patch elements integrated into the circuit board and configured to:
receive the radar signals having the first polarization type reflected from the object; and
receive the radar signals having a second polarization type reflected from the object.

### Claim 9 (depends on 1)

The radar device of claim 1,
wherein the first polarization type comprises right-hand circular polarization, and
wherein the second polarization type comprises left-hand circular polarization.

### Claim 10 (depends on 1)

The radar device of claim 1, wherein the processing circuitry is configured to determine the material category at least in part by forming a beam at an intermediate frequency of the transceiver circuitry.

### Claim 11 (depends on 1)

The radar device of claim 1, wherein the processing circuitry is further configured to:
determine a color for a graphical representation of the object; and
output, for display, a graphical user interface including the graphical representation of the object with the color.

### Claim 12 (depends on 1)

The radar device of claim 1, wherein the processing circuitry is configured to determine an electrical conductivity of the object based on the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object.

### Claim 13

A method for detecting an object, the method comprising:
causing transceiver circuitry to transmit radar signals having a first polarization type towards the object;
causing an antenna array of the transceiver circuitry to receive radar signals having the first polarization type reflected from the object;
causing the antenna array of the transceiver circuitry to receive radar signals having a second polarization type reflected from the object, the second polarization type being different than the first polarization type;
interleaving a first operating mode and a second operating mode;
determining reflectivity values for the radar signals having the first polarization type reflected from the object in the first operating mode;
determining reflectivity values for the radar signals having the second polarization type reflected from the object in the second operating mode; and
determining a material category of the object based on the reflectivity values for the radar signals having the first polarization type reflected from the object and the reflectivity values for the radar signals having the second polarization type reflected from the object.

### Claim 14 (depends on 13)

The method of claim 13, further comprising determining a power ratio of the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object,
wherein determining the material category of the object is based on the power ratio.

### Claim 15 (depends on 13)

The method of claim 13, further comprising determining a phase relationship between the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object, and
wherein determining the material category of the object is based on the phase relationship.

### Claim 16

A radar device configured to detect an object, the radar device comprising:
transceiver circuitry configured to:
transmit radar signals having a first polarization type towards the object;
receive radar signals having the first polarization type reflected from the object; and
receive radar signals having a second polarization type reflected from the object, the second polarization type being different than the first polarization type; and
processing circuitry configured to:
determine a power ratio of the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object;
determine a material category of the object based on the power ratio at least in part by:
determining a conductive material category for the object in response to determining that the power ratio of the radar signals exceeds a first threshold ratio; and
determining an insulative material category for the object in response to determining that the power ratio of the radar signals does is less than a second threshold ratio.

### Claim 17 (depends on 16)

The radar device of claim 16, wherein the processing circuitry is configured to determine the material category at least in part by selecting the material category from a set of material categories including a conductive surface, vegetation, and a human.

### Claim 18 (depends on 16)

The radar device of claim 16,
wherein the processing circuitry is further configured to determine a phase relationship between the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object, and
wherein the processing circuitry is configured to determine a material category of the object based on the phase relationship.

### Claim 19 (depends on 16)

The radar device of claim 16, wherein the processing circuitry is configured to determine the material category of the object based on an algorithm including, as input variables:
the power ratio of the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object; and
a phase relationship between the radar signals having the first polarization type reflected from the object and the radar signals having the second polarization type reflected from the object.

### Claim 20 (depends on 16)

The radar device of claim 16, wherein the transceiver circuitry comprises:
a circuit board;
transmit circuitry including a first array of patch elements integrated into the circuit board and configured to transmit the radar signals having the first polarization type; and
receiver circuitry including a second array of patch elements integrated into the circuit board and configured to:
receive the radar signals having the first polarization type reflected from the object; and
receive the radar signals having a second polarization type reflected from the object.