 Acoustic sub-surface interrogator |
| I claim: 1. A method for investigating sub-surface acoustical properties of a layered site, ... |
|
| Coherent frequency burst detector apparatus and method |
| OF A PREFERRED EMBODIMENT As mentioned above, the principles of this invention apply to the ... |
|
| Canopy for screening objects |
| An object of the present invention is to provide a canopy of the above kind that shall be a ... |
|
| Circuit including a phase shifter for generating signals for electronically scanned antennas |
| It is an object of the present invention to provide a circuit capable of generating RF signals with ... |
|
| Data recording apparatus |
| In view of the aforesaid aspect, it is an object of the present invention to provide a data ... |
|
| HF Antenna matching device |
| What is claimed is: 1. A HF antenna matching device comprising: a directional coupler having first ... |
|
| Coprocessor system and method |
| What is claimed is: 1. A coprocessor system, comprising: (a) antenna means located on a vehicle for ... |
|
| Position locating apparatus for an underwater moving body |
| It is therefore one object of the present invention to provide a position detecting apparatus for ... |
|
| Three dimensional range imaging system |
| OF PREFERRED EMBODIMENT Referring now to the drawing in detail, FIG. 1 diagrammatically ... |
|
| Protective headgear |
| We claim: 1. A protective headgear comprising: (a) a helmet, (b) a face mask of flexible material, ... |
|
|
Cross polarization compensation system
| Details |
Inventors: Yuuki, Hironori; Kurihara, Hiroshi; Baba, Noboru; Arai, Makoto; Inagaki, Kazunori; Yamada, Matsuichi;
Assignee: Kokusai Denshin Denwa Kabushiki Kaisha (Tokyo, JP)
Primary Examiner: Ng; Jin F.
Assistant Examiner: Chin; Tommy P.
Attorney, Agent or Firm: Burns; Robert E., Lobato; Emmanuel J., Adams; Bruce L.
A cross polarization compensation system, in which an input elliptically polarized wave is converted, by a first rotatable differential phase shifter having a phase shift of 90.degree. or less than 90.degree., into an elliptically polarized wave defined by .vertline..alpha..vertline.=.vertline.cot.sup.-1 .gamma..vertline. (where .alpha. is the tilt angle of an ellipse indicative of the elliptically polarized wave relative to a predetermined reference direction and .gamma. is the axial ratio for the ellipse), and then the phase delay or advance plane of a second rotatable differential phase shifter having a phase shift of the ellipse indicative of 90.degree. is disposed in alignment with the major axis of the converted elliptically polarized wave, thereby to obtain a linearly polarized wave having electric fields components of a desired direction. |
|
DETAILED DESCRIPTION This invention is to provide a cross polarization compensating system which is free from the abovesaid defects of the conventional cross polarization compensating systems using 90.
degree.
and 180.
degree.
differential phase shifters and with which it is possible to effectively compensate for cross polarization resulting from the non-isotropic property of a propagation path, in particular, cross polarization due to DPS.
To achieve the above object, in this invention, an input elliptically polarized wave is converted, by a first rotatable polarizer having a phase shift of 90.
degree.
or less than 90.
degree.
, into an elliptically polarized wave defined by .
vertline.
.
alpha.
.
vertline.
=.
vertline.
cot.
sup.
-1 .
gamma.
.
vertline.
(where .
alpha.
is the tilt angle of an ellipse indicative of the converted elliptically polarized wave to a predetermined reference direction and .
gamma.
is the axial ratio for the ellipse), and then the phase delay or advance plane of a second rotatable differential phase shifter having a phase shift of 90.
degree.
is disposed in alignment with the major axis of the converted elliptically polarized wave, thereby to obtain a linearly polarized wave having electric field components of a desired direction.
|
|
Telecommunications 
