Title:
RADIO DATA ACQUISITION DEVICE
Document Type and Number:
Japanese Patent JP3144291
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To minimize the size of a radio data acquisition device maintaining the transmission distance of questioning wave by making an antenna function selection means switch an antenna for reception to that for transmission during data transmission when transmission distance causes problem and function two antennas as array antennas.
SOLUTION: During data transmission of a question generator 50, a switch control circuit 10 switches switch circuits 6 and 7 based on control signal from a transmission data output circuit 9. A modulation circuit 2 modulates the output signal of a transmitter 1 as a carrier base on the output data of the circuit 9 and transmits as questioning wave from an antenna 4 via a distributor 3. In data reception state, the circuit 2 transmits the output signal of the transmitter 1 as questioning wave without modulation as it is from the antenna 4 via the distributor 3. And, during data transmission when the transmission distance is problem, the antenna 5 is switched to transmission by an antenna function selection means 53 and makes the antenna 4 and 5 function as array antenna.
Inventors:
Satoshi Yoshitake
Application Number:
JP795096A
Publication Date:
March 12, 2001
Filing Date:
January 22, 1996
Export Citation:
Assignee:
Yokogawa Electric Corporation
International Classes:
G01S13/75; G01S13/76; G01S13/79; H04B1/59; (IPC1-7): G01S13/75; H04B1/59
Domestic Patent References:
| JP6300837A | ||||
| JP634745A | ||||
| JP6148320A | ||||
| JP5126945A | ||||
| JP2260926A | ||||
| JP63121774A |
Attorney, Agent or Firm:
Masayasu Watanabe