System for controlling right of access to a vehicle

• US 6,803,882 B2
• Filed: 04/15/2003
• Issued: 10/12/2004
• Est. Priority Date: 04/11/2000
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Hoetzel, Juergen
• Primary Examiner(s): PHAN, THO GIA
• Application Number:
  US10/257,562
• Publication Number:
  US 20030156068A1
• Time in Patent Office: 546 Days
• Field of Search: 343/704, 343/711, 343/713, 340/426.11, 340/903, 340/933, 342/174
• US Class Current: 343/713
• CPC Class Codes: B60R 25/245 where the antenna reception area plays a role
• CPC Class Codes: G07C 2009/00388 code verification carried out according to the challenge/response method
• CPC Class Codes: G07C 2009/00555 comprising means to detect or avoid relay attacks
• CPC Class Codes: G07C 2009/00777 by induction
• CPC Class Codes: G07C 2209/63 Comprising locating means for detecting the position of the data carrier, i.e. within the vehicle or within a certain distance from the vehicle
• CPC Class Codes: G07C 9/00309 operated with bidirectional data transmission between data carrier and locks

Abstract

A system for verifying the access authorization to a vehicle has a vehicle-based transceiver unit which has at least two transmitting/receiving antennas spaced a distance apart in or on the vehicle, and it has a transponder unit which is set up for detection of its presence and for exchanging a predetermined identification request/response sequence through or with the transceiver unit within a predetermined detection area in or around the vehicle, wherein the transceiver unit has calculation/analyzing means which perform the detection of a position of the transponder unit by using a time and/or phase measurement based on a mathematical geometric method in response to a reply signal transmitted by the transponder and received by the at least two transmitting/receiving antennas in response to the identification request.

Claims

1. A system for verifying an access authorization to a vehicle, comprising:

a vehicle-based transceiver unit including at least two transmitting/receiving antennas spaced a distance apart one of in the vehicle and on the vehicle; and

a transponder unit for detecting a presence of the transceiver unit and for exchanging a predetermined identification request/response sequence one of through and with the transceiver unit within a predetermined detection area one of in and around the vehicle, wherein;

the transceiver unit includes a calculation/analyzing device that detects a position of the transponder unit by using at least one of a time measurement and a phase measurement based on a mathematical geometric operation in response to a reply signal transmitted by the transponder unit and received by the at least two transmitting/receiving antennas in response to an identification request.

2. The system as recited in claim 1, wherein:

the at least two transmitting/receiving antennas include three monopole transmitting/receiving antennas on two vehicle sides and at a rear of the vehicle.

3. The system as recited in claim 1, wherein:

the calculation/analyzing device ascertains a transit time difference between transmitting the identification request by one of the at least two transmitting/receiving antennas and detecting an identification response subsequently transmitted by the transponder unit in response to receipt of the identification request, and

the calculation/analyzing device determines the position of the transponder unit from the transit time difference thus ascertained and known position coordinates of the at least two transmitting/receiving antennas relative to a defined vehicle zero point.

4. The system as recited in claim 3, wherein:

during the position determination, the calculation/analyzing device assumes internal signal transit times to be constant and of equal length in processing the identification response received by the at least two transmitting/receiving antennas.

5. The system as recited in claim 1, wherein:

the calculation/analyzing device executes a position determination based on a phase analysis in addition to a position determination based on a transit time difference, and

a phase difference of identification responses received at the at least two transmitting/receiving antennas in response to the transmission of the identification request is determined.

6. The system as recited in claim 5, wherein:

the calculation/analyzing device joins a position measurement result based on the transit time difference with a position measurement result based on a measurement of the phase difference in order to increase a resolution.

7. The system as recited in claim 1, wherein:

the system does not allow access to the vehicle if a signal transit time determined by the calculation/analyzing device is greater than a predetermined maximum time.