METHOD AND APPARATUS FOR REDUCING ROUND TRIP LATENCY AND OVERHEAD WITHIN A COMMUNICATION SYSTEM

• US 20070064669A1
• Filed: 03/20/2006
• Published: 03/22/2007
• Est. Priority Date: 03/30/2005
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Nangia, Vijay, Classon, Brian, Love, Robert, Ghosh, Amitava, Stewart, Kenneth, Baum, Kevin
• Granted Patent: US 8,031,583 B2
• Time in Patent Office: Days
• US Class Current: 370/347
• CPC Class Codes: H04B 7/2656 for structure of frame, burst
• CPC Class Codes: H04L 1/1822 involving configuration of automatic repeat request [ARQ] with parallel processes

Abstract

During operation radio frames are divided into a plurality of subframes. Data is transmitted over the radio frames within a plurality of subframes, and having a frame duration selected from two or more possible frame durations.

Claims

1. A method for transmitting data within a communication system, the method comprising the steps of:

receiving data to be transmitted over a radio frame, wherein the radio frame is comprised of a plurality of subframes;

selecting a frame length comprising multiple subframes;

selecting a subframe type from one of two or more types of subframes for the multiple of subframes;

placing the data within the multiple subframes to produce multiple subframes of data; and

transmitting the frame having the multiple subframes of data and the subframe type over the radio frame.

2. The method of claim 1 wherein the subframe type is distinguished a parameter taken from the group consisting of:

a guard interval, a subcarrier spacing, a number of subcarriers, a FFT size, and a pilot format.

3. The method of claim 1 wherein the each subframe type from the two or more types of subframes comprises a differing number of OFDM symbols or a differing number single carrier FDMA symbols.

4. The method of claim 1 wherein one or more types of subframes comprise broadcast subframes and unicast subframes.

5. The method of claim 4 wherein the broadcast subframes and the unicast subframes comprise a cyclic prefix.

6. The method of claim 5 wherein a length of the cyclic prefix identifies if a particular subframe is a broadcast subframe or a unicast subframe.

7. The method of claim 1 further comprising the step of using a blank subframe for interference avoidance, interference measurements, or when data is not present in the frame.

8. The method of claim 1 further comprising the step of:

multiplexing common control channels into the radio frame.

9. The method of claim 8 wherein the common control channels comprises one or more of broadcast channels, paging channels, synchronization channels, random access channels, or pilot channels.

10. The method of claim 8 wherein the common control channels indicate a subframes and radio frames to be used for broadcast.

11. The method of claim 1 further comprising the step of:

inserting an overhead region within the radio frame and the radio frame comprises the plurality of subframes and an overhead region.

12. The method of claim 1 further comprising the step of:

determining a frame start in the radio frame via a presence of a pilot or control symbol within the radio frame.

13. The method of claim 1 further comprising the step of:

signaling a partition of the radio frame at system deployment, at registration within frame synchronization and control, within a designated subframe in a radio frame, within a first subframe in the radio frame, last subframe of a previous radio frame, or within a control assignment allocating resources.

14. The method of claim 1 wherein the step of transmitting the frame comprises the step of transmitting the frame in an allowed location.

15. The method of claim 1 wherein selecting a frame further comprises selecting a frame duration from two or more possible frame durations.

16. The method of claim 15 wherein the step of selecting the frame duration comprises the step of selecting the frame duration based on a user'"'"'s speed, Doppler, radio channel condition, carrier or channel bandwidth, user location in the cell, and data rate, QoS, latency requirement, packet size, error rate, allowable number of retransmissions a remote unit capability, a cell size, a carrier frequency, proximity to other wireless systems, a channel or carrier bandwidth, based on achieving backwards compatibility with another system, based on the number of users to be scheduled in a frame, based on the system load, based on or a number of users in each cell, based on a modulation type, or based on a traffic type.

17. The method of claim 15 wherein the frame duration is 2 ms, 1.67 ms, or 0.5 ms.

18. The method of claim 1 further comprising the step of:

placing a resource allocation control within the multiple subframes.

19. The method of claim 18 wherein the step of placing the resource allocation control comprises the step of time multiplexing the resource allocation control.

20. The method of claim 18 wherein the resource allocation control allocates resources for one user or more than one user.

21. The method of claim 18 wherein the resource allocation control contains uplink resource allocation and/or acknowledgment information.

22. The method of claim 18 wherein the resource allocation control comprises a persistent resource allocation that remains applicable for more than one frame.

23. The method of claim 18 wherein the persistent resource is persistent for a specified number of frames or radio frames or turned off with a control message in a different frame.

24. The method of claim 18 wherein the resource allocation control provides a location for resource allocation control for either a next frame or a rest of the radio frame.

25. The method of claim 18 further comprising the step of:

multiplexing a common control channel into the radio frame, wherein the common control channel indicates a of the location of the resource allocation control within the radio frame.

26. The method of claim 18 further comprising the step of:

selecting a second frame, wherein the resource allocation control allocates resources in the first frame and in the second frame.

27. The method of claim 18 further comprising the step of:

selecting a second frame;

placing within the multiple subframes an indication of the location of a resource allocation control for the second frame.

28. The method of claim 18 wherein selecting a frame further comprises selecting a frame duration from two or more possible frame durations.