Imaging system and method

Patent metadata

Field	Value
Publication number	US-9329263-B2
Application number	US-201213479120-A
Country	US
Kind code	B2
Filing date	May 23, 2012
Priority date	May 23, 2011
Publication date	May 3, 2016
Grant date	May 3, 2016

Abstract

An imaging system and method in which the system carries out the method which includes the steps of: (a) determining an incident field, (b) using the incident field and a volume integral equation (VIE) to determine a total field, (c) predicting voltage ratio measurement at a receiving antenna by using the volume integral equation (VIE), wherein the VIE includes a vector Green's function, (d) collecting voltage ratio measurements from one or more receiving antennas, and (e) comparing the predicted voltage ratio measurements to the collected voltage ratio measurements to determine one or more properties of the object being evaluated. An S-parameter based inverse scattering method using the vector Green's function and VIE as its core is also described.

First claim

The invention claimed is:

1. An imaging method, comprising the steps of:
(a) determining an incident field due to voltage excitation on a transmitting antenna;
(b) using the incident field and a volume integral equation (VIE) to determine a total field;
(c) predicting voltage ratio measurement at a receiving antenna by using the volume integral equation (VIE), including a vector Green's function, that directly converts electromagnetic vector field quantities in a computational domain to scalar quantities representing measured voltages at terminals of one or more receiving antennas;
(d) collecting voltage ratio measurements from the one or more receiving antennas;
(e) comparing the predicted voltage ratio measurements to the collected voltage ratio measurements to determine one or more properties of an object being evaluated; and
(f) generating an image of the object being evaluated.

2. The imaging method of claim 1 , wherein step (c) further comprises converting the volume integral equation (VIE) to S-parameters using the vector Green's function.

3. The imaging method of claim 1 , wherein the vector Green's function is a kernel within the volume integral equation (VIE).

4. The imaging method of claim 1 , further comprising the step of transmitting radiation towards an object prior to step (a).

5. An imaging system, comprising:
at least one transmitting antenna for transmitting probing field radiation towards a target object;
at least one receiving antenna for receiving at least some of the radiation that is scattered by the target object; and
a computer-based data collection system that operates to determine an incident field related to the transmitted radiation, determine a total field, directly compute a predicted receiving antenna voltage ratio measurement using a volume integral equation (VIE) that includes a vector Green's function converting electromagnetic vector field quantities in a computational domain to scalar quantities representing measured voltages at terminals of the receiving antenna, receive actual voltage ratio measurements from the one or more receiving antennas, determine at least one property of the target object using the computed voltage ratio measurement and the actual voltage ratio measurements, and generate an image of the target object being evaluated.

6. The imaging system of claim 5 , further comprising a plurality of the receiving antennas, wherein the data collection system includes a switching matrix connected to the receiving antennas.

7. The imaging system of claim 5 , wherein the data collection system functions as a multistatic radar system connected to the antennas.

8. The imaging system of claim 7 , wherein the data collection system includes a computer that is connected to the radar system via a radar control, and wherein the radar system provides radar data received from the one or more receiving antennas to the computer via a data collection interface.

9. The imaging system of claim 5 , wherein the antennas and data collection system are configured to permit imaging of soft animal tissues.

10. The imaging system of claim 5 , wherein the data collection system operates to convert the volume integral equation (VIE) to S-parameters using the vector Green's function.

11. The imaging system of claim 5 , wherein the vector Green's function is a kernel within the volume integral equation (VIE).

Assignees

• Haynes Mark Spencer
• Moghaddam Mahta
• Univ Michigan

Inventors

• Haynes Mark Spencer
• Moghaddam Mahta

Classifications

• G01S13/88

  Radar or analogous systems specially adapted for specific applications (electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00) · CPC title

• G01S7/412

  based on a comparison between measured values and known or stored values · CPC title

• G01S13/89 Primary

  for mapping or imaging · CPC title

• G01S2007/4082

  Physics · mapped topic

• G01S7/4082

  using externally generated reference signals, e.g. via remote reflector or transponder · CPC title