PRACH-based proximity detection

• US 9,814,073 B2
• Filed: 01/27/2014
• Issued: 11/07/2017
• Est. Priority Date: 01/30/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Barbieri, Alan, Xu, Hao, Jain, Vikas, Malladi, Durga Prasad, Khan, Awaiz Ahmad, Kotla, Samatha, Sachdev, Balwinderpal
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Farahmand, Ashil
• Application Number:
  US14/165,351
• Publication Number:
  US 20140211677A1
• Time in Patent Office: 1,380 Days
• Field of Search: None
• CPC Class Codes: G01S 5/0295 Proximity-based methods, e.g. position inferred from reception of particular signals
• CPC Class Codes: H04L 1/00 Arrangements for detecting or preventing errors in the information received correcting synchronisation H04L7/00
• CPC Class Codes: H04W 28/16 Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
• CPC Class Codes: H04W 52/0206 in access points, e.g. base stations access point devices per se H04W88/08
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/283 Power depending on the position of the mobile
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Improvements to signaling procedures for use in physical random access channel (PRACH)-based proximity detection are disclosed. Signaling and signaling processes from a serving base station may trigger a more efficient and reliable transmission of PRACH from related user equipment (UE). At the dynamic power nodes (DPNs) monitoring for such PRACH-based proximity, features are disclosed which establish neighbor lists for more efficient management of detection and proximity activation.

Claims

1. A method of wireless communication, comprising:

transmitting, from a serving base station, a signal to a mobile device in communication with the serving base station, wherein the signal triggers the mobile device to transmit periodic transmissions on a physical random access channel (PRACH) during a time period, wherein the mobile device remains in communication with the serving base station and continues decoding data received from the serving base station during the time period;

transmitting, by the serving base station, downlink data to the mobile device for decoding during the time period; and

receiving, by the serving base station, uplink data from the mobile device during the time period,

wherein the signal includes one or more of;

a signature sequence set for the periodic transmissions on the PRACH;

a transmit power delta for open loop transmission power control;

a fixed transmit power for the periodic transmissions on the PRACH; and

a proximity detection flag.

2. The method of claim 1, further comprising:

transmitting, from the serving base station, a deactivation signal to the mobile device, wherein the deactivation signal stops the periodic transmissions on the PRACH during the time period.

3. The method of claim 1, wherein the signal includes one or more of:

a duration of the periodic transmissions on the PRACH;

an interval of the periodic transmissions on the PRACH; and

a periodicity of the periodic transmissions on the PRACH.

4. The method of claim 1, wherein the one or more included in the signal further includes one or more of:

a decode continuation signal, wherein the decode continuation signal signals the mobile device to continue the decoding of the data received from the serving base station during the periodic transmissions on the PRACH; and

a combination of the one or more included in the signal, wherein the proximity detection flag indicates to the mobile device to use one of;

a standard transmit power and the fixed transmit power.

5. The method of claim 4, wherein the fixed transmit power includes one of:

a predetermined transmit power less than maximum transmit power of the mobile device; and

the maximum transmit power of the mobile device.

6. The method of claim 5, wherein the predetermined transmit power is signaled by a wireless communication network.

7. The method of claim 1, further comprising:

receiving, at the serving base station, a PRACH transmission from the mobile device during the periodic transmissions on the PRACH; and

delaying, by the serving base station, transmission of a PRACH acknowledgement message to the mobile device.

8. The method of claim 7, further comprising:

detecting a preamble in the received PRACH associated with the mobile device, wherein the delaying includes;

delaying transmission of the PRACH acknowledgement for a predetermined time.

9. An apparatus configured for wireless communication, comprising:

at least one processor; and

a memory coupled to the at least one processor,

wherein the at least one processor is configured;

to transmit, from a serving base station, a signal to a mobile device in communication with the serving base station, wherein the signal triggers the mobile device to transmit periodic transmissions on a physical random access channel (PRACH) during a time period, wherein the mobile device remains in communication with the serving base station and continues decoding data received from the serving base station during the time period;

to transmit, by the serving base station, downlink data to the mobile device for decoding during the time period; and

to receive, by the serving base station, uplink data from the mobile device during the time period,

wherein the signal includes one or more of;

a signature sequence set for the periodic transmissions on the PRACH;

a transmit power delta for open loop transmission power control;

a fixed transmit power for the periodic transmissions on the PRACH; and

a proximity detection flag.

10. The apparatus of claim 9, further comprising configuration of the at least one processor to transmit, from the serving base station, a deactivation signal to the mobile device, wherein the deactivation signal stops the periodic transmissions on the PRACH during the time period.

11. The apparatus of claim 9, wherein the signal includes one or more of:

a duration of the periodic transmissions on the PRACH;

an interval of the periodic transmissions on the PRACH; and

a periodicity of the periodic transmissions on the PRACH.

12. The apparatus of claim 9, wherein the one or more included in the signal further includes one or more of:

a decode continuation signal, wherein the decode continuation signal signals the mobile device to continue the decoding of the data received from the serving base station during the periodic transmissions on the PRACH; and

a combination of the one or more included in the signal, wherein the proximity detection flag indicates to the mobile device to use one of;

a standard transmit power and the fixed transmit power.

13. The apparatus of claim 9, further comprising configuration of the at least one processor:

to receive, at the serving base station, a PRACH transmission from the mobile device during the periodic transmissions on the PRACH; and

to delay, by the serving base station, transmission of a PRACH acknowledgement message to the mobile device.

14. A non-transitory computer-readable medium having program code recorded thereon, the program code comprising program code for causing a computer:

to transmit, from a serving base station, a signal to a mobile device in communication with the serving base station, wherein the signal triggers the mobile device to transmit periodic transmissions on a physical random access channel (PRACH) during a time period, wherein the mobile device remains in communication with the serving base station and continues decoding data received from the serving base station during the time period;

to transmit, by the serving base station, downlink data to the mobile device for decoding during the time period; and

to receive, by the serving base station, uplink data from the mobile device during the time period,

wherein the signal includes one or more of;

a signature sequence set for the periodic transmissions on the PRACH;

a transmit power delta for open loop transmission power control;

a fixed transmit power for the periodic transmissions on the PRACH; and

a proximity detection flag.

15. The non-transitory computer-readable medium of claim 14, further comprising:

program code for causing the computer to transmit, from the serving base station, a deactivation signal to the mobile device, wherein the deactivation signal stops the periodic transmissions on the PRACH during the time period.

16. The non-transitory computer-readable medium of claim 14, wherein the signal includes one or more of:

a duration of the periodic transmissions on the PRACH;

an interval of the periodic transmissions on the PRACH; and

a periodicity of the periodic transmissions on the PRACH.

17. The non-transitory computer-readable medium of claim 14, wherein the one or more included in the signal further includes one or more of:

a decode continuation signal, wherein the decode continuation signal signals the mobile device to continue the decoding of the data received from the serving base station during the periodic transmissions on the PRACH; and

a combination of the one or more included in the signal, wherein the proximity detection flag indicates to the mobile device to use one of;

a standard transmit power and the fixed transmit power.

18. The non-transitory computer-readable medium of claim 17, wherein the fixed transmit power includes one of:

a predetermined transmit power less than maximum transmit power of the mobile device; and

the maximum transmit power of the mobile device.

19. The non-transitory computer-readable medium of claim 18, wherein the predetermined transmit power is signaled by a wireless communication network.

20. The non-transitory computer-readable medium of claim 14, further comprising:

program code for causing the computer to receive, at the serving base station, a PRACH transmission from the mobile device during the periodic transmissions on the PRACH; and

program code for causing the computer to delay, by the serving base station, transmission of a PRACH acknowledgement message to the mobile device.

21. The non-transitory computer-readable medium of claim 20, further comprising:

program code for causing the computer to detect a preamble in the received PRACH associated with the mobile device, wherein the program code for causing the computer to delay includes;

program code for causing the computer to delay transmission of the PRACH acknowledgement for a predetermined time.

22. An apparatus configured for wireless communication, comprising:

means for transmitting, from a serving base station, a signal to a mobile device in communication with the serving base station, wherein the signal triggers the mobile device to transmit periodic transmissions on a physical random access channel (PRACH) during a time period, wherein the mobile device remains in communication with the serving base station and continues decoding data received from the serving base station during the time period;

means for transmitting, by the serving base station, downlink data to the mobile device for decoding during the time period;

means for receiving, by the serving base station, uplink data from the mobile device during the time period; and

means for transmitting, from the serving base station, a deactivation signal to the mobile device, wherein the deactivation signal stops the periodic transmissions on the PRACH during the time period,

wherein the signal includes one or more of;

a signature sequence set for the periodic transmissions on the PRACH;

a transmit power delta for open loop transmission power control;

a fixed transmit power for the periodic transmissions on the PRACH; and

a proximity detection flag.

23. The apparatus of claim 22, wherein the signal further includes one or more of:

a duration of the periodic transmissions on the PRACH;

an interval of the periodic transmissions on the PRACH;

a periodicity of the periodic transmissions on the PRACH;

a decode continuation signal, wherein the decode continuation signal signals the mobile device to continue decoding data received from the serving base station during the periodic transmissions on the PRACH; and

a combination thereof, wherein the proximity detection flag indicates to the mobile device to use one of;

a standard transmit power and the fixed transmit power.

24. The apparatus of claim 23, wherein the fixed transmit power includes one of:

a predetermined transmit power less than maximum transmit power of the mobile device; and

the maximum transmit power of the mobile device.

25. The apparatus of claim 24, wherein the predetermined transmit power is signaled by a wireless communication network.

26. The apparatus of claim 22, further comprising:

means for receiving, at the serving base station, a PRACH transmission from the mobile device during the periodic transmissions on the PRACH; and

means for delaying, by the serving base station, transmission of a PRACH acknowledgement message to the mobile device.

27. The apparatus of claim 26, further comprising:

means for detecting a preamble in the received PRACH associated with the mobile device, wherein the means for delaying includes;

means for delaying transmission of the PRACH acknowledgement for a predetermined time.