Techniques for Accessing a Wireless Communication System with Tune-Away Capability

• US 20110044300A1
• Filed: 11/05/2010
• Published: 02/24/2011
• Est. Priority Date: 02/03/2005
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Joshi, Abhay Arvind, Turner, Simon, Rezaiifar, Ramin
• Granted Patent: US 8,238,321 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

To access a first communication system, a terminal determines a transmission time for an access probe, an expected response time from the system, and a protected time interval based on the transmission time and/or expected response time. The terminal determines a starting time for sending the access probe such that the protected time interval does not overlap a tune-away interval in which the terminal is to monitor anther frequency/air-interface. This starting time may be set initially to the end of a prior access probe plus a pseudo-random wait duration and may be advanced forward or moved backward in time, if needed, by a time duration selected such that the protected time interval does not overlap the tune-away interval.

Claims

1. A processor comprising:

a first module for causing a computer to determine a protected time interval required after an access request is sent to a first communication system, wherein the first communication system is entitled to respond anytime within the protected time interval;

a second module for causing the computer to determine a starting time for sending the access request such that the protected time interval does not overlap a tune-away interval; and

a third module for causing the computer to initiate sending the access request to the first communication system at the starting time.

2. The processor of claim 1, further comprising:

a module for causing the computer to tune a receiver to the first communication system during the protected time interval and to tune away from the first communication system during the tune-away interval.

3. The processor of claim 2, further comprising a module for causing the computer to direct the receiver to tune to a second communication system prior to the tune-away interval and to direct the receiver to tune back to the first communication system after the tune-away interval.

4. The processor of claim 3, further comprising a module for causing the computer to receive a paging channel from the second communication system during the tune-away interval.

5. The processor of claim 1, further comprising a module for causing the computer to determine an expected response time for an acknowledgment from first communication system for the access request, and determine the protected time interval based on the expected response time.

6. The processor of claim 1, further comprising a module for causing the computer to determine a transmission time for the access request, determine the protected time interval further based on the transmission time.

7. The processor of claim 1, further comprising a module for causing the computer to determine an initial time for sending the access request, and set the starting time to the initial time plus or minus a zero or non-zero time duration selected such that transmission of the access request at the starting time results in the protected time interval not overlapping the tune-away interval.

8. The processor of claim 7, further comprising a module for causing the computer to determine a pseudo-random wait duration and to set the initial time to the end of a prior access request plus the pseudo-random wait duration.

9. The processor of claim 1, further comprising a module for causing the computer to initialize the starting time to the end of a prior access request, to determine a pseudo-random wait duration, to advance the starting time by the pseudo-random wait duration, and to repeat determining a pseudo-random wait duration and advancing the starting time until transmission of the access request at the starting time results in the protected time interval not overlapping the tune-away interval.

10. The processor of claim 1, wherein the tune-away interval corresponds to an assigned paging slot for a second communication system.

11. The processor of claim 1, wherein the tune-away interval corresponds to a pilot transmission or a signaling transmission from a second communication system.

12. The processor of claim 1, wherein the tune-away interval corresponds to a measurement interval for a second communication system.