DIGITAL RADIO COMMUNICATION

• US 20160128117A1
• Filed: 06/04/2014
• Published: 05/05/2016
• Est. Priority Date: 06/05/2013
• Status: Active Grant

• Current Assignee: Nordic Semiconductor ASA
• Original Assignee: Nordic Semiconductor ASA
• Inventors: ENGELIEN-LOPES, David Alexandre, WICHLUND, Sverre, CORBISHLEY, Phil
• Granted Patent: US 9,681,477 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 17/373 Predicting channel quality or other radio frequency [RF] parameters
• CPC Class Codes: H04L 5/1438 Negotiation of transmission parameters prior to communication modified according to link quality H04L1/0001
• CPC Class Codes: H04L 5/1446 of transmission speed
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
• CPC Class Codes: H04W 76/14 Direct-mode setup
• CPC Class Codes: H04W 76/19 Connection re-establishment
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 84/20 Master-slave selection or change arrangements

Abstract

A method of digital radio communication between a first device (2) and a second device (8), where each device comprises a radio transmitter (4, 10) and a radio receiver (6, 12), the method comprising: a) said first and second devices (2, 8) establishing a connection using a predetermined protocol having at least one predefined message format; b) if said connection is subsequently broken, said second device (8) transmitting an advertising message at a first data rate indicating a desire to reconnect; and c) if a reconnection is not established, said second device (8) transmitting a further advertising message at a second data rate indicating a desire to reconnect, wherein said second data rate is lower than the first data rate.

Claims

1. A method of digital radio communication between a first device and a second device, each comprising a radio transmitter and a radio receiver, the method comprising:

a) said first and second devices establishing a connection using a predetermined protocol having at least one predefined message format;

b) if said connection is subsequently broken, said second device transmitting an advertising message at a first data rate indicating a desire to reconnect; and

c) if a reconnection is not established, said second device transmitting a further advertising message at a second data rate indicating a desire to reconnect, wherein said second data rate is lower than the first data rate.

2. A method as claimed in claim 1 wherein the first device comprises a master device and the second device comprises a slave device.

3. A method as claimed in claim 1 wherein the lower data rate results from at least part of said further advertising message being encoded using a coding scheme in which at least some bits specified in said predefined message format are represented by a plurality of bits transmitted.

4. A method as claimed claim 3 wherein said coding scheme comprises a respective fixed sequence of chips to represent each data bit.

5. A method as claimed in claim 1 comprising the first and second devices agreeing during a connection that the second device will transmit said further advertising message if necessary to establish the reconnection.

6. A method as claimed in claim 1 comprising the second device transmitting a plurality of advertising messages at the first data rate.

7. A method as claimed in claim 1 further comprising said second device transmitting a further advertising message at the first data rate indicating a desire to reconnect.

8. A method as claimed in claim 1 comprising d) if a reconnection is not established at said second data rate, said second device transmitting a further advertising message at a third data rate indicating a desire to reconnect, wherein said third data rate is lower than the second data rate.

9. A method as claimed in claim 1 comprising said second device cycling through a plurality of available data rates for advertisement messages.

10. A method as claimed in claim 1 comprising the first device listening for messages at both said first and second data rates.

11. A method as claimed in claim 1 comprising the first and second devices conducting subsequent communication at a data rate applied to the advertisement message received by the second device in order to establish the reconnection.

12. A method as claimed in claim 11 comprising changing said data rate if a criterion is met.

13. A method as claimed in claim 12 wherein the criterion comprises a measure of a quality of signal between the first and second devices.

14. A method as claimed in claim 12 wherein said criterion comprises an estimate of the received signal strength from one of the devices to the other device.

15. A method as claimed in claim 11 comprising changing the data rate if the received signal strength of one device is determined to be above or below a threshold level.

16. A method as claimed in claim 1 wherein the predetermined protocol is compatible with a Bluetooth™

or Bluetooth Low Energy™

protocol.

17. A method as claimed in claim 16 wherein the advertising message and the further advertising message form part of one or more Advertising events in accordance with a Bluetooth™

protocol.

18. A digital radio device comprising a radio transmitter and a radio receiver, the device being arranged:

a) to establish a connection with another device using a predetermined protocol having at least one predefined message format;

b) if said connection is subsequently broken, to transmit an advertising message at a first data rate indicating a desire to reconnect; and

c) if a reconnection is not established, to transmit a further advertising message at a second data rate indicating a desire to reconnect, wherein said second data rate is lower than the first data rate.

19. A device as claimed in claim 18 wherein the lower data rate results from at least part of said further advertising message being encoded using a coding scheme in which at least some bits specified in said predefined message format are represented by a plurality of bits transmitted.

20. A device as claimed claim 19 wherein said coding scheme comprises a respective fixed sequence of chips to represent each data bit.

21. A device as claimed in claim 18 arranged to agree with the other device during a connection to transmit said further advertising message if necessary to establish the reconnection.

22. A device as claimed in claim 18 arranged to transmit a plurality of advertising messages at the first data rate.

23. A device as claimed in claim 18 arranged to transmit a further advertising message at the first data rate indicating a desire to reconnect.

24. A device as claimed in claim 18 arranged d) if a reconnection is not established at said second data rate, to transmit a further advertising message at a third data rate indicating a desire to reconnect, wherein said third data rate is lower than the second data rate.

25. A device as claimed in claim 18 arranged to cycle through a plurality of available data rates for advertisement messages.

26. A device as claimed in claim 18 arranged to conduct subsequent communication with the other device at a data rate applied to the advertisement message received by the device in order to establish the reconnection.

27. A device as claimed in claim 26 arranged to change said data rate if a criterion is met.

28. A device as claimed in claim 27 wherein the criterion comprises a measure of a quality of signal between from the other device.

29. A method as claimed in claim 27 wherein said criterion comprises an estimate of the received signal strength from the other device.

30. A device as claimed in claim 26 arranged to change the data rate if the received signal strength from the other device is determined to be above or below a threshold level.

31. A device as claimed in claim 18 wherein the predetermined protocol is compatible with a Bluetooth™

or Bluetooth Low Energy™

protocol.

32. A device as claimed in claim 31 wherein the advertising message and the further advertising message form part of one or more Advertising events in accordance with a Bluetooth™

specification.

33. A digital radio communication system comprising a first device and a second device, each comprising a radio transmitter and a radio receiver, wherein:

a) said first and second devices are arranged to establish a connection using a predetermined protocol having at least one predefined message format;

b) if said connection is subsequently broken, said second device is arranged to transmit an advertising message at a first data rate indicating a desire to reconnect; and

c) if a reconnection is not established, said second device is arranged to transmit a further advertising message at a second data rate indicating a desire to reconnect, wherein said second data rate is lower than the first data rate.

34. A digital radio communication system as claimed in claim 33 wherein one or both of said first and second devices are arranged:

a) to establish a connection with another device using a predetermined protocol having at least one predefined message format;

b) if said connection is subsequently broken, to transmit an advertising message at a first data rate indicating a desire to reconnect; and

c) if a reconnection is not established, to transmit a further advertising message at a second data rate indicating a desire to reconnect, wherein said second data rate is lower than the first data rate.