Moving-body communication device

• US 5,952,940 A
• Filed: 07/15/1998
• Issued: 09/14/1999
• Est. Priority Date: 07/16/1997
• Status: Expired due to Term

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Matsumoto, Manabu
• Primary Examiner(s): Hofsass, Jeffrey A.
• Assistant Examiner(s): PHAM, TOAN NGOC
• Application Number:
  US09/115,591
• Time in Patent Office: 426 Days
• Field of Search: 340/905, 340/928, 340/917, 340/930, 340/931, 340/938
• US Class Current: 340/905
• CPC Class Codes: G07B 15/063 using wireless information transmission between the vehicle and a fixed station identification of vehicles G08G
• CPC Class Codes: G08G 1/017 identifying vehicles G08G1/015, G08G1/054 take precedence

Abstract

When a vehicle-mounted device receives a FCM signal from a road-side communication device, the vehicle-mounted device receives or transmits a data signal in accordance with a link direction and a time slot specified by the FCM signal. When the vehicle-mounted device does not receive a signal to be received within an expected time, or when it transmits an ACK signal which is a last signal of communication, retry processing starts. In this retry processing, the vehicle-mounted device determines the contents of communication processing to be next carried out from both the contents of the signal transmitted from the road-side communication device and the contents of the last time communication processing.

Claims

1. A moving-body communication device which is mounted on a moving body and starts to communicate with an interrogator in response to a signal from the interrogator to execute a sequence of communication processing when passing through a communication area of the interrogator, said moving-body communication device comprising:

a communication control device for carrying out a retry processing which controls progress of said communication processing to be continued in consideration of a progressing state of said communication processing which has already been carried out, when the moving-body communication device does not receive a signal that is transmitted from the interrogator and is to be received thereby within an expected time,

wherein said communication control device allows a data signal to be received or to be transmitted in accordance with a link direction representing that the data signal is to be received by said moving-body communication device or is to be transmitted from said moving-body communication device, said link direction being specified by the signal transmitted from said interrogator, and

wherein said communication control device carries out a step of said communication processing in accordance with contents of a signal transmitted from said interrogator after said retry processing starts, when the link direction specified by the signal transmitted from said interrogator after said retry processing starts is different from that specified by the signal from said interrogator immediately before said retry processing starts and when the progressing state of said communication processing is not in a last step.

2. A moving-body communication device according to claim 1, wherein said communication control device controls progress of said communication processing in accordance with contents of a signal that said moving-body communication device receives from said interrogator after said retry processing starts.

3. A moving-body communication device according to claim 2, wherein said communication control device stops said communication processing and starts communication again from the beginning when said moving body communication device does not receive a signal from said interrogator within a predetermined retry time after said retry processing starts.

4. A moving-body communication device according to claim 1, wherein said communication control device allows the data signal to be received or to be transmitted at timing specified by the signal transmitted from said interrogator.

5. A moving-body communication device according to claim 1, wherein communication control device allows a response signal to be transmitted at timing specified by the signal transmitted from said interrogator to start to communicate therewith.

6. A moving-body communication device according to claim 1, wherein said communication control device carries out a step of said communication processing identical to that carried out immediately before said retry processing starts, when the link direction specified by the signal transmitted from said interrogator after said retry processing starts is the same as that specified by the signal from said interrogator immediately before said retry processing starts.

7. A moving-body communication device according to claim 1, wherein said communication control device carries out said retry processing after a last signal of said communication processing is transmitted from said moving-body communication device, and said communication control determines that said communication processing is completed when said moving-body communication device receives a signal which does not include an instruction with respect to the link direction from said interrogator in said retry processing.

8. A moving-body communication device which is mounted on a moving body and starts to communicate with an interrogator in response to a signal from the interrogator to execute a sequence of communication processing when passing through a communication area of the interrogator, said moving-body communication device comprising:

a communication control device for carrying out a retry processing which controls progress of said communication processing to be continued in consideration of a progressing state of said communication processing which has already been carried out, when the moving-body communication device does not receive a signal that is transmitted from the interrogator and is to be received thereby within an expected time,

wherein said communication control device allows a data signal to be received or to be transmitted in accordance with a link direction representing that the data signal is to be received by said moving-body communication device or is to be transmitted from said moving-body communication device, said link direction being specified by the signal transmitted from said interrogator, and

wherein said communication control device stops said communication processing as it is incomplete, when the link direction specified by the signal transmitted from said interrogator after said retry processing starts is different from that specified by the signal from said interrogator immediately before said retry processing starts and when the progressing state of said communication processing is in a last step.

9. A moving-body communication device which is mounted on a moving body and starts to communicate with an interrogator in response to a signal from the interrogator to execute a sequence of communication processing when passing through a communication area of the interrogator, said moving-body communication device comprising:

a communication control device for carrying out a retry processing which controls progress of said communication processing to be continued in consideration of a progressing state of said communication processing which has already been carried out, when the moving-body communication device does not receive a signal that is transmitted from the interrogator and is to be received thereby within an expected time,

wherein said communication control device allows a data signal to be received or to be transmitted in accordance with a link direction representing that the data signal is to be received by said moving-body communication device or is to be transmitted from said moving-body communication device, said link direction being specified by the signal transmitted from said interrogator, and

wherein said communication control device determines that said communication processing is completed, when said moving-body communication device receives a signal which does not include an instruction with respect to the link direction from said interrogator after said retry processing starts and when the progressing state of said communication processing is in a last step.

10. A moving-body communication device which is mounted on a moving body and starts to communicate with an interrogator in response to a signal from the interrogator to execute a sequence of communication processing when passing through a communication area of the interrogator, said moving-body communication device comprising:

a communication control device for carrying out a retry processing which controls progress of said communication processing to be continued in consideration of a progressing state of said communication processing which has already been carried out, when the moving-body communication device does not receive a signal that is transmitted from the interrogator and is to be received thereby within an expected time,

wherein said communication control device allows a data signal to be received or to be transmitted in accordance with a link direction representing that the data signal is to be received by said moving-body communication device or is to be transmitted from said moving-body communication device, said link direction being specified by the signal transmitted from said interrogator, and

wherein said communication control device stops said communication processing as it is incomplete, when said moving-body communication device receives a signal which does not include an instruction with respect to the link direction from said interrogator after said retry processing starts and when the progressing state of said communication processing is not in a last step.

11. A vehicle-mounted device which is mounted on a vehicle and starts to communicate with a road-side communication device in response to a radio signal from said road-side communication device to execute a sequence of communication processing when passing through a communication area of said road-side communication device, said moving-body communication device comprising:

a communication control device for determining a step of said communication processing to be continued when deciding an occurrence of a reception error of an acknowledgement signal from contents of last time communication processing and contents of present communication processing,

wherein said communication control device allows a data signal to be received or to be transmitted in accordance with a link direction representing that the data signal is to be received by said vehicle-mounted device or is to be transmitted from said vehicle-mounted device, said link direction being specified by the signal transmitted from said road-side communication device, and

wherein said communication control device decides that the reception error of the acknowledgement signal occurs at said road-side communication device when the signal transmitted from said road-side communication device in said present communication processing has the same link direction as that specified by the signal of said last time communication processing after said acknowledgement signal is transmitted from the vehicle-mounted device to said road-side communication device.

12. A vehicle-mounted device according to claim 11, wherein said communication control device prohibits carrying out a step of said communication processing in accordance with the signal transmitted from said road-side communication device in said present communication processing.

13. A vehicle-mounted device according to claim 12, wherein said communication control device allows the acknowledgement signal to be transmitted again in response to the signal transmitted from said road-side communication device in said present communication processing.