Frame structures supporting voice or streaming communications with high speed data communications in wireless access networks

• US 20050201368A1
• Filed: 05/09/2005
• Published: 09/15/2005
• Est. Priority Date: 01/20/2000
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Leo L. Strawczynski, Shalini S. Periyalwar, Wen Tong
• Inventors: Tong, Wen, Periyalwar, Shalini S., Strawczynski, Leo L.
• Granted Patent: US 7,596,123 B2
• Time in Patent Office: Days
• US Class Current: 370/356
• CPC Class Codes: H04B 7/2656 for structure of frame, burst
• CPC Class Codes: H04J 3/1682 Allocation of channels according to the instantaneous demands of the users, e.g. concentrated multiplexers, statistical multiplexers
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0007 by modifying the frame length
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0068 by puncturing
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04W 74/02 Hybrid access
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 99/00 Subject matter not provided for in other groups of this subclass

Abstract

A frame structure that is ordinarily optimized for providing variable high data rates also includes the flexibility to efficiently carry lower data rate, lower latency frames using sub-framing. Superframes, each comprised of a predetermined number of frames, carry voice and data communications at one or more variable data rates. The size of a superframe is limited, such as by the delay tolerance for voice transmission, typically 20 ms. Each voice customer is allotted one or more frames or portions of frames within the superframe, called sub-frames, as is needed to deliver the lower data rate, low latency voice communication. The allocation for the voice customers is not fixed, but varies as the data rate varies over time. Any bits in a frame that are not needed to carry voice communication are assigned to carry data having compatible data rate requirements. Additionally, the sub-framing concept may be extended to include ATM cells.

Claims

1. A method of operating a base station to wirelessly transmit voice or streaming communications and data communications to a plurality of user terminals on a carrier, the method comprising:

repeatedly and sequentially wirelessly transmitting time division multiplexed superframes to the plurality of user terminals on the carrier, wherein each time division multiplexed superframe comprises a plurality of frames, wherein at least one of the frames carries voice communications, and wherein at least one of the frames carries data communications;

for each frame carrying voice communications, transmitting a plurality of voice packets contained in the frame;

wherein each voice packet includes voice bits for a respective user; and

wherein each voice packet includes a preamble having a user identifier and an indication of the length of the voice packet.

2. The method of claim 1, wherein at least one Walsh function is employed to identify the user and to indicate the length of a voice packet.

3. The method of claim 2, wherein a single Walsh function both identifies the respective user and indicates the length of the voice packet.

4. The method of claim 2, wherein:

a first unique Walsh function of the preamble identifies the user; and

a second unique Walsh function of the preamble indicates the length of voice packet.

5. The method of claim 4, wherein:

the first unique Walsh function is modulated on the carrier during a first time period of the preamble; and

the second unique Walsh function is modulated on the carrier during a second time period of the preamble.

6. The method of claim 5, wherein both the first unique Walsh function and the second unique Walsh function are modulated on an in-phase portion of the carrier.

7. The method of claim 3, wherein:

the first unique Walsh function is modulated on an in-phase portion of the carrier; and

the second unique Walsh function is modulated on the quadrature-phase portion of the carrier.

8. The method of claim 7, wherein the first unique Walsh function and the second unique Walsh function are concurrently modulated on the carrier.

9. The method of claim 1, wherein at least one voice packet also includes a pointer to a subsequent voice packet.

10. The method of claim 9, wherein at least one Walsh function is employed to identify the user and to indicate the length of a voice packet.

11. A superframe embodied on a carrier that carries voice or streaming communications and data communications intended for a plurality of user terminals, the superframe comprising:

a plurality of frames, wherein at least one of the frames carries voice communications, and wherein at least one of the frames carries data communications;

for each frame carrying voice communications, a plurality of voice packets contained in the frame;

wherein each voice packet includes voice bits for a respective user; and

wherein each voice packet includes a preamble having a user identifier and an indication of the length of the voice packet.

12. The superframe of claim 11, wherein at least one Walsh function is employed to identify the user and to indicate the length of a voice packet.

13. The superframe of claim 12, wherein a single Walsh function both identifies the respective user and indicates the length of the voice packet.

14. The superframe of claim 12, wherein:

a first unique Walsh function of the preamble identifies the user; and

a second unique Walsh function of the preamble indicates the length of voice packet.

15. The superframe of claim 14, wherein:

the first unique Walsh function is modulated on the carrier during a first time period of the preamble; and

the second unique Walsh function is modulated on the carrier during a second time period of the preamble.

16. The superframe of claim 15, wherein both the first unique Walsh function and the second unique Walsh function are modulated on an in-phase portion of the carrier.

17. The superframe of claim 14, wherein:

the first unique Walsh function is modulated on an in-phase portion of the carrier; and

the second unique Walsh function is modulated on the quadrature-phase portion of the carrier.

18. The superframe of claim 17, wherein the first unique Walsh function and the second unique Walsh function are concurrently modulated on the carrier.

19. The method of claim 11, wherein at least one voice packet also includes a pointer to a subsequent voice packet.

20. The method of claim 19, wherein at least one Walsh function is employed to identify the user and to indicate the length of a voice packet.