Radio frequency sensing and localization of objects

Patent metadata

Field	Value
Publication number	US-12372602-B2
Application number	US-202217965679-A
Country	US
Kind code	B2
Filing date	Oct 13, 2022
Priority date	Oct 13, 2022
Publication date	Jul 29, 2025
Grant date	Jul 29, 2025

Abstract

A device includes a transmitter coupled to an antenna, a receiver coupled to the at least one antenna, and a processing device to: cause the transmitter to radiate a radio frequency (RF) signal; receive, via the receiver, a reflective RF signal based on the radiated RF signal; detect, within a data array of the reflective RF signal, a maximum peak among a plurality of signal peaks, the maximum peak being indicative of a first distance to a first object relative to the at least one antenna; and cancel, using cascading peak cancellation on the spectrum, the maximum peak while detecting a first next-highest peak of the plurality of signal peaks compared to the maximum peak, the first next-highest peak being indicative of a second distance to a second object.

First claim

What is claimed is:

1. A device comprising:
a transmitter coupled to at least one antenna;
a receiver coupled to the at least one antenna; and
a processing device coupled to the transmitter and the receiver, the processing device to:
cause the transmitter to radiate a radio frequency (RF) signal;
receive, via the receiver, a reflective RF signal based on the radiated RF signal;
detect, within a data array of the reflective RF signal, a maximum peak among a plurality of signal peaks, the maximum peak being indicative of a first distance to a first object relative to the at least one antenna; and
cancel, using cascading peak cancellation on the data array, the maximum peak while detecting a first next-highest peak of the plurality of signal peaks compared to the maximum peak, the first next-highest peak being indicative of a second distance to a second object.

2. The device of claim 1 , wherein the processing device is further to generate the data array, from the reflective RF signal, comprising information about a likelihood of objects being located at different distances, wherein, to detect the maximum peak, the processing device is to apply a detection function to the data array.

3. The device of claim 1 , wherein the processing device is further to:
determine whether the first next-highest peak has an amplitude satisfying a threshold amplitude; and
in response to the amplitude not satisfying the threshold amplitude, report the maximum peak as correlating to the first distance and terminate the cascading peak cancellation.

4. The device of claim 1 , wherein, to detect and cancel the maximum peak, the processing device is to:
locate the maximum peak by applying a first steering vector, within a first detection function, to the data array that correlates to the first distance;
determine the second distance associated with the first next-highest peak that correlates to a second steering vector; and
remove, using the second steering vector, the maximum peak from the data array.

5. The device of claim 4 , wherein, to detect the first next-highest peak, the processing device is further to:
remove a weight associated with the first distance from a search set of the first steering vector to generate a weighted search set; and
integrate the weighted search set into the second steering vector to generate a second detection function, wherein the second detection function is equivalent to the first distance multiplied by the weight to a determined power.

6. The device of claim 1 , wherein the processing device is further to:
determine that the first next-highest peak has an amplitude that satisfies a threshold amplitude; and
cancel, using the cascading peak cancellation, the first next-highest peak of the plurality of signal peaks while detecting a second next-highest peak of the plurality of signal peaks, the second next-highest peak being indicative of a third distance to a third object.

7. The device of claim 6 , wherein, to detect and cancel the first next-highest peak, the processing device is further to:
locate the first next-highest peak by applying a second steering vector, within a second detection function, to the data array that generates the second distance; and
determine the third distance associated with the second next-highest peak using a weighted search set, within a third detection function, that also removes the first next-highest peak from the data array; and
wherein, to detect the second next-highest peak, the processing device is further to generate the third detection function by one of:
multiplying, by the first distance, a product of the square of a first steering vector used to determine the first distance and the square of a second steering vector used to determine the second distance; or
multiplying, by the first distance, a difference between the second distance and the first distance.

8. A method comprising:
detecting, within a data array of a reflective radio frequency (RF) signal, a maximum peak among a plurality of signal peaks, the maximum peak being indicative of a first path distance to a first object relative to an RF wireless device, the first path being one of multiple paths reflective to or from the first object;
determining that an amplitude of the maximum peak satisfies a threshold amplitude that is defined by a noise floor; and
canceling, using cascading peak cancellation on the data array, by the RF wireless device, the maximum peak while detecting a first next-highest peak of the plurality of signal peaks compared to the maximum peak, the first next-highest peak being indicative of a second path distance to the first object.

9. The method of claim 8 , further comprising generating the data array by the RF wireless device from the reflective RF signal, the data array comprising information about a likelihood of objects being located at different path distances, wherein the detecting comprises applying a detection function to the data array.

10. The method of claim 8 , further comprising:
determining whether the first next-highest peak has an amplitude satisfying a threshold amplitude; and
in response to the amplitude not satisfying the threshold amplitude, reporting the maximum peak as correlating to the first path distance and terminating the cascading peak cancellation.

11. The method of claim 8 , wherein detecting and canceling the maximum peak further comprises:
locating the maximum peak by applying a first steering vector, within a first detection function, to the data array that correlates to the first path distance;
determining the second path distance associated with the first next-highest peak that correlates to a second steering vector; and
removing, using the second steering vector, the maximum peak from the data array.

12. The method of claim 11 , wherein detecting the first next-highest peak further comprises:
removing a weight associated with the first path distance from a search set of the first steering vector to generate a weighted search set; and
integrating the weighted search set into the second steering vector to generate a second detection function, wherein the second detection function is equivalent to the first path distance multiplied by the weight to a determined power.

13. The method of claim 8 , further comprising:
determining that the first next-highest peak has an amplitude that satisfies a threshold amplitude; and
canceling, using the cascading peak cancellation, the first next-highest peak of the plurality signal peaks while detecting a second next-highest peak of the plurality of signal peaks, the second next-highest peak being indicative of a third path distance to the first object.

14. The method of claim 13 , wherein detecting and canceling the first next-highest peak further comprises:
locating the first next-highest peak by applying a second steering vector, within a second detection function, to the data array that generates the second path distance; and
determining the third path distance associated with the second next-highest peak using a weighted search set, within a third detection function, that also removes the first next-highest peak from the data array; and
wherein detecting the second next-highest peak further comprises generating the third detection function by one of:
multiplying, by the first distance, a product of the square of a first steering vector used to determine the first path distance and the square of a second steering vector used to determine the second path distance; or
multiplying, by the first path distance, a difference between the second path distance and the first path distance.

Assignees

• Cypress Semiconductor Corp

Inventors

• Kolych Igor
• Uln Kiran

Classifications

• G01S5/0273

  using multipath or indirect path propagation signals in position determination · CPC title

• G01S5/06

  Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements (G01S5/12 takes precedence) · CPC title

• G01S2013/9316

  combined with communication equipment with other vehicles or with base stations · CPC title

• G01S2013/462

  using multipath signals · CPC title

• G01S13/765

  with exchange of information between interrogator and responder · CPC title