Title:
ANTENNA SYSTEM
Document Type and Number:
Japanese Patent JP3895455
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To correctly catch, track a main wave of a desired wave and enable stable reception by rotating an antenna in an azimuth direction, stopping the antenna at a position where an electric field level higher than a threshold value is detected and catching the desired wave.
SOLUTION: A received radio wave from an antenna 13 is input to a reception channel-setting part 14. A wave from a desired reception channel is detected by a wave-detecting part 15, and the intensity of a detected electric field is detected by a reception level-detecting part 16. The information is input to a comparison circuit 17. The comparison circuit 17 compares an S level information showing the intensity of the detected electric field with a threshold value M, and outputs a detected S level exceeding the threshold value M to a memory 18 to store the level. It is judged whether or not a desired wave exceeding the threshold value is detected when the antenna 13 is rotated once. If no desired wave is detected, a spare channel is changed over and the antenna 13 is rotated once in an azimuth direction.
Inventors:
Keiichi Nonaka
Kitagawa Osamu
Kitagawa Osamu
Application Number:
JP7125998A
Publication Date:
March 22, 2007
Filing Date:
March 06, 1998
Export Citation:
Assignee:
Japan Radio Co., Ltd.
International Classes:
G01S3/42; H01Q3/02; H01Q3/04; H04B7/26; (IPC1-7): G01S3/42; H01Q3/02; H01Q3/04; H04B7/26
Domestic Patent References:
| JP7321533A | ||||
| JP829512A | ||||
| JP750512A | ||||
| JP375385A | ||||
| JP818324A |
Attorney, Agent or Firm:
Kenji Yoshida
Jun Ishida
Jun Ishida
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