SUB-CHANNEL SELECTION TO REDUCE LATENCY OF CIRCUIT-SWITCHED FALLBACK

• US 20150063315A1
• Filed: 08/30/2013
• Published: 03/05/2015
• Est. Priority Date: 08/30/2013
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: YANG, Ming, CHIN, Tom, SHI, Guangming
• Application Number:
  US14/015,774
• Publication Number:
  US 20150063315A1
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04J 2013/165 Joint allocation of code together with frequency or time
• CPC Class Codes: H04J 3/1694 Allocation of channels in TDM/TDMA networks, e.g. distributed multiplexers Passive Optical Networks H04Q11/0062
• CPC Class Codes: H04W 36/00224 between packet switched [PS] and circuit switched [CS] network technologies, e.g. circuit switched fallback [CSFB]
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/085 collision avoidance
• CPC Class Codes: H04W 76/50 for emergency connections

Abstract

It is determined whether a specific call type occurs. A random access preamble is transmitted at an earliest available sub-channel when the specific call type occurs. The random access preamble is transmitted at an assigned sub-channel when the specific call type does not occur. The call type can be a circuit switched fall back (CSFB) call or an emergency call.

Claims

1. A method of wireless communication, comprising:

determining whether a specific call type occurs;

transmitting a random access preamble at an earliest available sub-channel when the specific call type occurs; and

transmitting the random access preamble at an assigned sub-channel when the specific call type does not occur.

2. The method of claim 1, in which the earliest available sub-channel is an uplink pilot channel (UpPCH) in a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA) network.

3. The method of claim 1, in which the random access preamble is a synchronous uplink sequence (SYNC-UL) in a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA) network.

4. The method of claim 1, in which the specific call type is a circuit switched fall back (CSFB) call.

5. The method of claim 1, in which the specific call type is an emergency call.

6. An apparatus for wireless communication, comprising:

means for determining whether a specific call type occurs;

means for transmitting a random access preamble at an earliest available sub-channel when the specific call type occurs; and

means for transmitting the random access preamble at an assigned sub-channel when the specific call type does not occur.

7. The apparatus of claim 6, in which the earliest available sub-channel is an uplink pilot channel (UpPCH) in a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA) network.

8. The apparatus of claim 6, in which the random access preamble is a synchronous uplink sequence (SYNC-UL) in a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA) network.

9. The apparatus of claim 6, in which the specific call type is a circuit switched fall back (CSFB) call.

10. The apparatus of claim 6, in which the specific call type is an emergency call.

11. A computer program product for wireless communication in a wireless network, comprising:

a non-transitory computer-readable medium having non-transitory program code recorded thereon, the program code comprising;

program code to determine whether a specific call type occurs;

program code to transmit a random access preamble at an earliest available sub-channel when the specific call type occurs; and

program code to transmit the random access preamble at an assigned sub-channel when the specific call type does not occur.

12. The computer program product of claim 11, in which the earliest available sub-channel is an uplink pilot channel (UpPCH) in a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA) network.

13. The computer program product of claim 11, in which the random access preamble is a synchronous uplink sequence (SYNC-UL) in a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA) network.

14. The computer program product of claim 11, in which the specific call type is a circuit switched fall back (CSFB) call.

15. The computer program product of claim 11, in which the specific call type is an emergency call.

16. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory, the at least one processor being configured;

to determine whether a specific call type occurs;

to transmit a random access preamble at an earliest available sub-channel when the specific call type occurs; and

to transmit the random access preamble at an assigned sub-channel when the specific call type does not occur.

17. The apparatus of claim 16, in which the earliest available sub-channel is an uplink pilot channel (UpPCH) in a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA) network.

18. The apparatus of claim 16, in which the random access preamble is a synchronous uplink sequence (SYNC-UL) in a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA) network.

19. The apparatus of claim 16, in which the specific call type is a circuit switched fall back (CSFB) call.

20. The apparatus of claim 16, in which the specific call type is an emergency call.