Title:
RADIO WAVE DIRECTION DETECTION SYSTEM AND RADIO WAVE DIRECTION DETECTION METHOD
Document Type and Number:
WIPO Patent Application WO/2021/171535
Kind Code:
A1
Abstract:
A mobile station 10a measures the current position of an antenna 11a of the station and detects the phase difference between a reception signal for radio waves 30 and a local frequency synchronized between mobile stations. Similarly, a mobile station 10b measures the current position of an antenna 11b of the station and detects the phase difference between a reception signal for radio waves 30 and the local frequency synchronized between the mobile stations. Subsequently, a radio wave direction detection device 13a installed in the mobile station 10a estimates the arrival direction of the radio waves 30 on the basis of the current positions of the antennas and the phase differences at the times of reception obtained by the mobile station 10a and mobile station 10b.
Inventors:
OBATA AKIRA (JP)
SUZUKI YASUHIKO (JP)
SUZUKI YASUHIKO (JP)
Application Number:
PCT/JP2020/008235
Publication Date:
September 02, 2021
Filing Date:
February 28, 2020
Export Citation:
Assignee:
HITACHI INT ELECTRIC INC (JP)
International Classes:
G01S3/48; G01S5/04
Foreign References:
| JP2017504787A | 2017-02-09 | |||
| JP2007256004A | 2007-10-04 | |||
| JPH02140680A | 1990-05-30 | |||
| JP2006238264A | 2006-09-07 | |||
| JP2000124961A | 2000-04-28 |
Attorney, Agent or Firm:
TAMURA Chikashi et al. (JP)
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