EP0693741A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Mobile object identification device
Assignee: Denso Corp
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Filing: 1995-07-19
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Granted: —
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Expires: 2015-07-19
Abstract
Abstract A communication area for an antenna (30) disposed on a toll collection gate (24) and a communication area for a responder unit (23a through 23e, hereinafter,IU) mounted on an automobile are arranged to coincide with each other, and communication failure in intervening areas when a plurality of communication areas are formed in a toll collection area. When an IU (23a through 23e) mounted on an automobile (22) receives a pilot signal-wave, it modulates a carrier-radio-wave-signal which is subsequently transmitted thereto with a responding data-signal and transmits the modulated-carrier-radio-wave as a responding signal-wave. In this system, the output power of the responding signal-wave is attenuated during the round trip of the carrier-radio-wave. Therefore, the output power thereof is decreased from an original level when the pilot signal-wave is transmitted. On the other hand, when other signal waves are transmitted, their output power are restored to the original level, thereby equalizing the power of the responding signal of the IU (23a through 23e) and that of the communication signals from the antenna (30) thereby ensuring steady communication.
Inventors
- 👤 Toshihide Ando
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 09:07
CPC Classifications
G; G07; G07B; G07B15/00; G07B15/06; G07B15/063; G08; G08G; G08G1/00; G08G1/01; G08G1/017
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
174 words
A mobile object identification device for a communication area where information is exchanged between a mobile object (22, 22a through 22e) and a station (24) comprising: an antenna control unit (28, 25a through 25e) having an antenna (30) disposed at said station (24) for transmitting a communication signal-wave and an unmodulated carrier-radio-wave through an antenna (30) toward said communication area and receiving a responding signal-wave from said communication area; a responder unit (23a through 23e) mounted on said mobile object (22, 22a through 22e) for transmitting said responding signal-wave when receiving said communication signal-wave and said unmodulated carrier-radio-wave subsequently, said responder unit (23a through 23e)including a receiving circuit receiving an unmodulated carrier-radio-wave from said communication area, a control circuit generating a responding data-signal and a transmitting circuit modulating said unmodulated carrier-radio-wave with said responding data-signal and transmitting a modulated carrier-radio-wave as said responding signal-wave; and means (36) for decreasing output power of said antenna (30) to a prescribed level while said antenna (30) control unit (28, 25a through 25e) is transmitting said communication signal.
Claim 2
Dependent Claim
27 words
A mobile object identification device claimed in claim 1 further comprising a gate (24) for toll collection, wherein said antenna (30) is disposed on said gate (24).
Claim 3
Dependent Claim
35 words
A mobile object identification device claimed in claim 2, wherein said antenna (30) control unit (28, 25a through 25e) comprises means (31, 32, 33, 36) for transmitting a interrogatory signal-wave and said unmodulated carrier-radio-wave subsequently.
Claim 4
Dependent Claim
26 words
A mobile object identification device claimed in claim 3 further comprising a signal-processing-circuit (29) for processing data for said toll collection when receiving said responding signal-wave,
Claim 5
Dependent Claim
30 words
A mobile object identification device claimed in claim 2, wherein said antenna control unit (28, 25a through 25e) further comprises a plurality of antennas (30) disposed on said gate (24).
Claim 6
Dependent Claim
46 words
A mobile object identification device claimed in claim 5, wherein said antenna controll unit (28, 25a through 25e) further comprises means (32, 36) for generating said carrier-radio-waves having different frequencies and assigning said carrier-radio-waves said antennas (30) corresponding to said communication areas overlapping with one another.
Claim 7
Dependent Claim
49 words
A mobile object identification device claimed in claim 6, wherein said means (32, 36) for generating said carrier-radio-waves having different frequenies further comprises circuit means (36) for supplying said communication signal-waves at different timings to said antennas (30) corresponding to those of said communication areas overlapping with one another.
Claim 8
Dependent Claim
38 words
A mobile object identification device claimed in claim 4, wherein said responder unit (23a through 23e)includes a communication program which controls said unit to stop communication for a given period after said toll collection process has been completed.
Claim 9
Dependent Claim
40 words
A mobile object identification device claimed in claim 4, wherein said responder unit (23a through 23e) includes a communication program which controls said unit to stop communication until a given running distance after said toll collection process has been completed.
Claim 10
Dependent Claim
49 words
A mobile object identification device claimed in claim 2, wherein said antenna control unit (28, 25a through 25e) comprises means (32, 36) for transmitting a pilot signal-wave and an unmodulated-carrier-radio-wave successively, and an interrogatory signal wave subsequent to receiving said responding signal-wave from said responder unit (23a through 23e).
Claim 11
Dependent Claim
34 words
A mobile object identification device claimed in claim 10, wherein said responder unit (23a through 23e)includes a communication program which controls last said unit to stop communication until it has received said pilot signal-wave.
Claim 12
Dependent Claim
42 words
A mobile object identification device claimed in claim 11, wherein said responder unit (23a through 23e)includes a communication program which controls last said unit to prohibit communication with others when it has received a pilot signal-wave from one of said antennas (30).
Claim 13
Dependent Claim
36 words
A mobile object identification device claimed in claim 11, wherein said means (32, 36) for transmitting said pilot signal-wave and interrogatory signal wave transmit said pilot signal-wave at a power level lower than said interrogatory signal-wave.
Claim 14
Dependent Claim
31 words
A mobile object identification device claimed in claim 11, wherein said means (32, 36) for transmitting said unmodulated-carrier-wave transmits said unmodulated carrier-radio-wave at the same power level as said interrogatory signal-wave.
References Cited (Backward Citations)
No citation records indexed.
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