Polling method and vehicle search method in digital radio communication system

• US 20070165591A1
• Filed: 08/25/2004
• Published: 07/19/2007
• Est. Priority Date: 08/27/2003
• Status: Abandoned Application

• Current Assignee: Hitachi Kokusai Electric Incorporated (Hitachi, Ltd.)
• Original Assignee: Hitachi Kokusai Electric Incorporated (Hitachi, Ltd.)
• Inventors: Kanazawa, Masayuki, Hiraki, Yuzo, Sakaihori, Minoru, Higure, Kin'ichi
• Application Number:
  US10/569,627
• Publication Number:
  US 20070165591A1
• Time in Patent Office: Days
• US Class Current: 370/346
• CPC Class Codes: G08G 1/20 Monitoring the location of vehicles belonging to a group, e.g. fleet of vehicles, countable or determined number of vehicles
• CPC Class Codes: H04L 27/2078 in which the phase change per symbol period is constrained coset coding H04L27/186
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services

Abstract

The present invention provides a polling method in a radio digital communication system making it possible to shorten time required for polling without causing increase in an error rate and to efficiently manage and administrate communications. In a digital radio communication system for collecting information from a plurality of terminal stations by polling, a polling response signal to be transmitted from each terminal station to a base station has a frame format constructed of a one-frame in which a cyclic bit pattern is placed at a leading end of the frame format.

Claims

1. A polling method in a digital radio communication system for collecting information from a plurality of terminal stations by polling, wherein a polling response signal to be transmitted from each terminal station to a base station has a frame format constructed of a one-frame in which a cyclic bit pattern is placed at a leading end of the frame format.

2. The polling method in a digital radio communication system according to claim 1, wherein a modulating system for signal transfer is the π

/4 shift QPSK system, and all bits in the cyclic bit pattern are “

0”

.

3. The polling method in a digital radio communication system according to claim 1, wherein the modulating system for signal transfer is the π

/4 shift QPSK system, and each of all bits in the cyclic bit pattern are a repetitive bit pattern comprising binary values of “

1”

and “

0”

.

4. A vehicle search method in a digital radio communication system for collecting information from a plurality of terminal stations into a base station by polling, wherein a polling response signal to be transmitted from each terminal station to the base station has a frame format constructed of a one-frame in which a cyclic bit pattern is placed at a leading end of the frame format, and the base station collects information from the terminal stations based on the polling response signal constructed of the one-frame in response to a request for allocation of a vehicle from a client.