Multiple-band identification and ranging

Patent metadata

Field	Value
Publication number	US-9747736-B2
Application number	US-201414452464-A
Country	US
Kind code	B2
Filing date	Aug 5, 2014
Priority date	Aug 5, 2014
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

A long-range power-efficient multiple-band identification system and method includes, for example, a base-station control module and paired electronic key fob. The base-station control module and paired electronic key fob is arranged to provide a UHF (ultra-high frequency) wake transmitter for transmitting a wakeup signal in a UHF frequency range to the paired electronic key. When in range, the electronic key is awakened by the wakeup signal and in response transmits an acknowledgment reply to the base-station control module. After receiving the acknowledgment, the base-station control module transmits a relatively high power localization signal for determining an electronic key location.

First claim

What is claimed is:

1. A control system, comprising:
a UHF (ultra-high frequency) transmitter arranged for transmitting to a paired electronic key a UHF wakeup signal having a frequency in a UHF frequency range;
a receiver for receiving an acknowledgement reply transmitted from the paired electronic key in response to the UHF wakeup signal; and
an LF (low frequency) transmitter that is arranged to transmit a plurality of LF wakeup signals comprising adjacent LF wakeup signals to the paired electronic key, wherein the UHF transmitter transmits one or more UHF wakeup signals in between the transmission of each adjacent LF wakeup signal of the plurality of LF wakeup signals, wherein the plurality of LF wakeup signals is transmitted in response to a determination that a measured amount of UHF noise exceeds a threshold.

2. The system of claim 1 , wherein the UHF (ultra-high frequency) transmitter and the LF transmitter are powered by a transportable power source.

3. The system of claim 2 further comprising a processor for evaluating the acknowledgement reply to authenticate the paired electronic key and to grant access to a secure area when the acknowledgement reply has been successfully authenticated.

4. The system of claim 3 , wherein the secure area is inside of a vehicle for transporting the transportable power source.

5. The system of claim 1 , wherein the LF transmitter is installed in the vehicle.

6. The system of claim 5 , comprising the LF transmitter arranged for transmitting to the paired electronic key the plurality of LF wakeup signals having a frequency in an LF frequency range, wherein the LF transmitter consumes more power transmitting the plurality of LF wakeup signals than the power that is consumed by the UHF transmitter when transmitting the UHF wakeup signal.

7. The system of claim 6 , wherein an LF wakeup signal range is less than a UHF wakeup signal range.

8. The system of claim 6 , wherein the UHF transmitter is arranged to stop transmitting the UHF wakeup signal when the paired key is in an active mode.

9. An electronic key, comprising:
a UHF (ultra-high frequency) receiver arranged for receiving from a paired electronic base-station UHF wakeup signals having a frequency in a UHF frequency range;
a transmitter for generating an acknowledgement reply transmitted from the electronic key in response to the UHF wakeup signals; and
an LF (low frequency) receiver that is arranged to receive a plurality of LF wakeup signals comprising adjacent LF wakeup signals after transmitting the acknowledgement reply, wherein the UHF receiver is arranged to receive the UHF wakeup signals in between the reception of each adjacent LF wakeup signal, wherein the LF wakeup signals are received in response to a determination that a measured amount of UHF noise exceeds a threshold.

10. The electronic key of claim 9 , wherein the UHF frequency range is 300 MHz-2.4 GHz, and the LF wakeup signals have a frequency range of 18-150 Khz.

11. The electronic key of claim 9 , wherein the electronic key has a physical format of a key fob; and the UHF receiver and the LF receiver are powered by a portable power source.

12. The electronic key of claim 11 , wherein the acknowledgement reply that is transmitted in response to receiving of the UHF wakeup signals is a UHF acknowledgement reply.

13. A method of authentication, comprising:
transmitting from a base-station to a paired electronic key a UHF wakeup signal having a frequency in a UHF frequency range;
receiving at the base-station an acknowledgement reply transmitted from the paired electronic key in response to the UHF wakeup signal; and
transmitting LF localization signals in response to receiving the acknowledgement reply, wherein the localization signals are for determining a location of the paired electronic key; and
transmitting from the base-station to the paired electronic key a plurality of LF wakeup signals comprising adjacent LF wakeup signals having a frequency in a LF frequency range, wherein one or more UHF wakeup signals is transmitted in between the transmission of each adjacent LF wakeup signal, wherein the plurality of LF wakeup signals is transmitted in response to a determination that a measured amount of UHF noise exceeds a threshold.

14. The method of claim 13 , wherein the paired electronic key is powered by portable power source and the base-station is powered by a transportable power source.

15. The method of claim 14 , comprising waking up the electronic key in response to receiving one of the UHF wakeup signal and the LF wakeup signal.

Assignees

• Texas Instruments Deutschland

Inventors

• Austen Jürgen Stefan
• Graul Jens
• Hagl Andreas

Classifications

• H04W52/0225

  using monitoring of external events, e.g. the presence of a signal · CPC title

• G07C9/00896

  specially adapted for particular uses · CPC title

• G07C2209/63

  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 title

• H04W4/02 Primary

  Services making use of location information · CPC title

• G07C2009/00357

  and the lock having more than one limited data transmission ranges · CPC title