Backscatter estimation using progressive self interference cancellation

Patent metadata

Field	Value
Publication number	US-2016266245-A1
Application number	US-201415033889-A
Country	US
Kind code	A1
Filing date	Nov 14, 2014
Priority date	Aug 9, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

Techniques for estimating one or more backscatter signals reflected from one or more objects are disclosed. In one example, a backscatter sensor includes, in part, a receiver for receiving a composite signal comprising one or more reflections of a transmitted signal, each reflection being reflected by one of a plurality of objects; and a processor configured to estimate at least a first backscatter component of the composite signal using a progressive interference cancellation technique. The first backscatter component of the composite signal corresponds to a reflection of the transmitted signal from a first object. In one embodiment, the backscatter sensor includes multiple receivers and/or one or more transmitters.

First claim

What is claimed is:

1 . A backscatter sensor, comprising:
a receiver for receiving a composite signal comprising one or more reflections of a transmitted signal, each reflection being reflected by one of a plurality of objects; and a processor configured to:
estimate at least a first backscatter component of the composite signal using a progressive interference cancellation technique, wherein the first backscatter component of the composite signal corresponds to a reflection of the transmitted signal from a first object.

2 . The backscatter sensor of claim 1 , wherein the receiver further comprises:
a plurality of receive antennas, each receive antenna being coupled to a receive chain, wherein each receive chain receives a modified copy of the composite signal.

3 . The backscatter sensor of claim 1 , further comprising:
a transmitter for transmitting the transmitted signal, and wherein the processor further receives a sample of the transmitted signal.

4 . The backscatter sensor of claim 3 , wherein the transmitter comprises one or more transmitters, each transmitter transmitting a signal.

5 . The backscatter sensor of claim 1 , wherein the processor is further configured to estimate at least one of an amplitude of the first backscatter component, a phase of the first backscatter component and a time delay between transmission of the transmitted signal and reception of the first backscatter component.

6 . The backscatter sensor of claim 1 , wherein the processor is further configured to:
remove the estimated first backscatter component from the composite signal to generate a second signal; and estimate a second backscatter component using the second signal, the second backscatter component corresponding to a reflection of the transmitted signal from a second object.

7 . The backscatter sensor of claim 1 , wherein the first object is the closest object to the receiver among the plurality of objects.

8 . The backscatter sensor of claim 1 , wherein the processor is further configured to estimate one or more parameters associated with at least the first backscatter component using a linear optimization technique.

9 . The backscatter sensor of claim 8 , wherein the processor is further configured to estimate the one or more parameters in accordance with the following expression:

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Assignees

• Univ Leland Stanford Junior

Inventors

• Bharadia Dinesh
• Joshi Kiran
• Katti Sachin

Classifications

• G01S13/003 Primary

  Bistatic radar systems; Multistatic radar systems · CPC title

• G01S7/292

  Extracting wanted echo-signals · CPC title

• G01S7/038

  Feedthrough nulling circuits · CPC title

• G01S13/42

  Simultaneous measurement of distance and other co-ordinates (indirect measurement G01S13/46) · CPC title