|
|
Patent Number: |
7495764 |
|
|
Case ID: |
0 |
|
|
Patent Title:
|
Coherent radar and ladar polarimeter
|
|
|
Status: |
ACTIVE |
|
|
Status Date: |
8/27/2009 9:11:45 AM |
|
|
Issue Date:
|
2/24/2009 |
|
|
Filed Date:
|
7/25/2003 |
|
|
Serial #:
|
0/631,218 |
|
|
Assignee Name:
|
The United States of America as represented by the Secretary of the Army
(Washington,
DC)
|
|
|
Inventor(s):
|
McMillan, Robert W. , Holder, Ernest J. |
|
|
|
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to devices and methods for determining a state of polarization of an electromagnetic signal and, more particularly, to determining the state of polarization of the signal in an efficient and rapid manner.
2. Related Art
Knowledge of the state of polarization of a signal reflected from a target scene provides a powerful means of discriminating real targets from clutter and background. In general, natural backgrounds giving rise to clutter reflect electromagnetic
energy with little change in polarization, while man-made objects cause depolarization of these signals.
In the same way, knowledge of the polarization of electromagnetic radiation emitted passively from a target scene provides a powerful means of discriminating real targets from clutter and background. In general, the emission polarization
signatures of manmade objects will be different from that of na . . . . More |
|
|
|
|
A polarimeter includes a receiver that is configured to receive a first
polarization (P1) of the signal and to split the first polarization of
the signal into the in-phase (I.sub.P1) and quadrature (Q.sub.P1)
components and to receive a second polarization (P2) of the signal and to
split the second polarization of the signal into the in-phase (I.sub.P2)
and quadrature (Q.sub.P2) components. The polarimeter may also include a
processor that is configured to receive each of the in-phase and
quadrature components ((I.sub.P1), (Q.sub.P1), (I.sub.P2), and
(Q.sub.P2)) of the first and second polarizations and to determine the
Stokes polarization vector components (s.sub.0, s.sub.1, s.sub.2, and
s.sub.3) of the signal.
|
|
|
|
|
What is claimed is:
1. A polarimeter, comprising: a receiver that is configured to: receive a first polarization (P1) of a signal and to split the first polarization of the signal into the
in-phase (I.sub.P1) and quadrature (Q.sub.P1) components; and receive a second polarization (P2) of the signal and to split the second polarization of the signal into the in-phase (I.sub.P2) and quadrature (Q.sub.P2) components; and a processor that is
configured to: receive each of the in-phase and quadrature components ((I.sub.P1), (Q.sub.P1), (I.sub.P2), and (Q.sub.P2)) of the first and second polarizations; and determine the Stokes polarization vector components (s.sub.0, s.sub.1, s.sub.2, and
s.sub.3) of the signal.
2. The polarimeter of claim 1 wherein the Stokes polarization vector components (s.sub.0, s.sub.1, s.sub.2, and s.sub.3) of the signal are determined by: s.sub.0=a.sub.P1.sup.2+a.sub.P2.sup.2; s.sub.1=a.sub.P1.sup.2-a.sub.P2.sup.2;
s.sub.2=2a.sub.P1a.sub.P2 co . . . . More |
|
|
|
|
Print This Page
