Multi-media broadcast and multicast service (MBMS) in a wireless communications system

• US 20030207696A1
• Filed: 05/06/2002
• Published: 11/06/2003
• Est. Priority Date: 05/06/2002
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Wei, Yongbin, Chen, Tao, Vayanos, Alkinoos Hector, Willenegger, Serge
• Granted Patent: US 7,177,658 B2
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H03M 13/09 Error detection only, e.g. using cyclic redundancy check [CRC] codes or single parity bit
• CPC Class Codes: H03M 13/1515 Reed-Solomon codes
• CPC Class Codes: H03M 13/152 Bose-Chaudhuri-Hocquenghem [BCH] codes
• CPC Class Codes: H03M 13/19 Single error correction without using particular properties of the cyclic codes, e.g. Hamming codes, extended or generalised Hamming codes
• CPC Class Codes: H03M 13/23 using convolutional codes, e.g. unit memory codes
• CPC Class Codes: H03M 13/2707 Simple row-column interleaver, i.e. pure block interleaving
• CPC Class Codes: H03M 13/2915 with an error detection code in one dimension
• CPC Class Codes: H03M 13/2957 Turbo codes and decoding
• CPC Class Codes: H03M 13/373 with erasure correction and erasure determination, e.g. for packet loss recovery or setting of erasures for the decoding of Reed-Solomon codes
• CPC Class Codes: H04B 1/712 Weighting of fingers for combining, e.g. amplitude control or phase rotation using an inner loop
• CPC Class Codes: H04B 2201/70707 Efficiency-related aspects
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0017 where the mode-switching is based on Quality of Service requirement
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0027 Scheduling of signalling, e.g. occurrence thereof
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/0067 Rate matching H04L1/0013 and H04L1/08 take precedence
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/0083 Formatting with frames or packets; Protocol or part of protocol for error control
• CPC Class Codes: H04L 1/08 : by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04W 52/322 : Power control of broadcast channels
• CPC Class Codes: H04W 52/325 : Power control of control or pilot channels
• CPC Class Codes: H04W 52/327 : Power control of multicast channels
• CPC Class Codes: H04W 52/40 : during macro-diversity or soft handoff

Abstract

Techniques to implement MBMS services in a wireless communication system. In one aspect, a method is provided for processing data for transmission to a plurality of terminals. Frames of information bits (which may have variable rates) are provided to a buffer implementing a matrix. The matrix is padded with padding bits based on a particular padding scheme to support variable frame rates. The frames are then coded based on a particular block code to provide parity bits. The frame of information bits and the parity bits are then transmitted to the terminals. In another aspect, a method is provided for controlling the transmit power of a data transmission to a plurality of terminals. In accordance with the method, TPC streams are received from the terminals and processed to obtain a stream of joint power control commands used to adjust the transmit power of the data transmission.

Claims

1. In a wireless communication system, a method for processing data for transmission to a plurality of terminals, comprising:

providing a plurality of frames of information bits to a buffer implementing a matrix, wherein the frames may have variable rates and each frame may include a particular number of information bits that is different from those of other frames provided to the matrix;

padding the matrix with padding bits based on a particular padding scheme; and

coding the plurality of frames of information bits based on a particular code to provide a plurality of parity bits, and wherein the frames of information bits and the parity bits are transmitted to the plurality of terminals.

2. The method of claim 1, wherein one frame is provided to each row of the matrix, and wherein an unused portion of each row is padded with padding bits.

3. The method of claim 2, wherein each row of the matrix has a size M corresponding to a maximum number of information bits expected to be received for a frame.

4. The method of claim 2, wherein each row of the matrix has a size M corresponding to less than a maximum number of information bits expected to be received for a frame.

5. The method of claim 2, wherein each row of the matrix has a size M corresponding to an average number of information bits expected to be received for a frame.

6. The method of claim 4, wherein the matrix includes a fixed number of frames of information bits.

7. The method of claim 6, wherein the particular code used to code the plurality of frames in the matrix is selected based on a particular number of rows of information bits in the matrix.

8. The method of claim 4, wherein each matrix includes a fixed number of rows of information bits.

9. The method of claim 8, wherein the particular code used to code the plurality of frames in the matrix is selected based on a particular number of frames occupying multiple rows in the matrix.

10. The method of claim 1, wherein the plurality of frames are provided to the matrix without padding, and wherein only an unused portion of a last row of information bits is padded with padding bits.

11. The method of claim 1, wherein the plurality of frames are coded code column-wise in the matrix with a block.

12. The method of claim 11, wherein the block code is a linear block code.

13. The method of claim 11, wherein the block code is a systematic block code.

14. The method of claim 11, wherein only parity bits in columns of the matrix having information bits are transmitted to the plurality of terminals.

15. The method of claim 1, further comprising:

transmitting information indicative of a structure of the matrix to the plurality of terminals.

16. In a wireless communication system, a method for controlling transmit power of a data transmission to a plurality of terminals, comprising:

receiving a plurality of uplink transmit power control (TPC) streams from the plurality of terminals;

processing the plurality of uplink TPC streams to obtain a stream of joint power control commands for the data transmission; and

adjusting the transmit power of the data transmission based on the stream of joint power control commands.

17. The method of claim 16, wherein a single uplink TPC stream is received from each of the plurality of terminals.

18. The method of claim 17, wherein the single uplink TPC stream received from each terminal includes power control commands for controlling transmit powers of multiple downlink data transmissions to the terminal, and wherein one of the multiple downlink data transmissions is the data transmission to the plurality of terminals.

19. The method of claim 18, wherein the single uplink TPC stream includes a power control command for each power control interval, and wherein the power control command is set to increase transmit power if an increase in transmit power is needed for any of the multiple downlink data transmissions.

20. The method of claim 16, wherein the joint power control command for each power control interval is determined based a plurality of power control commands in the plurality of uplink TPC streams received from the plurality of terminals for that power control interval.

21. The method of claim 20, wherein the joint power control command for each power control interval is set to increase the transmit power of the data transmission if any power control command received in the plurality of uplink TPC streams for that power control interval requests an increase in transmit power for the data transmission.

22. The method of claim 16, wherein for each of the plurality of terminals, one uplink TPC stream is received from the terminal for each downlink data transmission to be power controlled.

23. The method of claim 16, further comprising:

sending a downlink TPC stream to each of the plurality of terminals.

24. The method of claim 23, wherein a plurality of downlink TPC streams are transmitted to the plurality of terminals in a multiplexed manner on a single power control channel.

25. The method of claim 23, wherein the plurality of downlink TPC streams are transmitted to the plurality of terminals in a time division multiplexed manner on the single power control channel.

26. In a wireless communication system, a method for broadcasting data to a plurality of terminals, comprising:

processing data for transmission to the plurality of terminals;

broadcasting the processed data on a first physical channel to the plurality of terminals; and

broadcasting control information on a second physical channel to the plurality of terminals, wherein the control information is used by the terminals to receive the data broadcasted on the first physical channel.

27. In a wireless communication system, a method for broadcasting data to a plurality of terminals, comprising:

determining a plurality of frames, in a time-division multiplexed (TDM) physical channel, to be used for broadcasting data to the plurality of terminals;

processing data for transmission to the plurality of terminals; and

broadcasting the processed data on the plurality of frames in the TDM physical channel.

28. The method of claim 27, further comprising:

repeating the broadcasting of the processed data over multiple frames to improve likelihood of correct reception by the plurality of terminals.

29. The method of claim 27, wherein the plurality of frames are reserved for broadcasting data.

30. The method of claim 27, wherein the plurality of frames are dynamically allocated for broadcasting data.

31. The method of claim 30, further comprising:

transmitting signaling to identify the plurality of frames dynamically allocated for broadcasting data.

32. A memory communicatively coupled to a digital signal processing device (DSPD) capable of interpreting digital information to:

provide a plurality of frames of information bits to a buffer implementing a matrix, wherein the frames may have variable rates and each frame may include a particular number of information bits that is different from those of other frames provided to the matrix;

pad the matrix with padding bits based on a particular padding scheme; and

code the plurality of frames of information bits based on a particular code to provide a plurality of parity bits, and wherein the frames of information bits and the parity bits are transmitted to the plurality of terminals

33. An apparatus in a wireless communication system, comprising:

means for providing a plurality of frames of information bits to a buffer implementing a matrix, wherein the frames may have variable rates and each frame may include a particular number of information bits that is different from those of other frames provided to the matrix;

means for padding the matrix with padding bits based on a particular padding scheme; and

means for coding the plurality of frames of information bits based on a particular code to provide a plurality of parity bits, and wherein the frames of information bits and the parity bits are transmitted to the plurality of terminals.

34. A transmitter in a wireless communication system, comprising:

a TX data processor operative to

provide a plurality of frames of information bits to a buffer implementing a matrix, wherein the frames may have variable rates and each frame may include a particular number of information bits that is different from those of other frames provided to the matrix,

pad the matrix with padding bits based on a particular padding scheme, and

code the plurality of frames of information bits based on a particular code to provide a plurality of parity bits, and wherein the frames of information bits and the parity bits are transmitted to the plurality of terminals; and

a transmitter operative to process the coded data to provide a modulated signal for transmission to a plurality of terminals.

35. An apparatus in a wireless communication system, comprising:

means for receiving a plurality of uplink transmit power control (TPC) streams from a plurality of terminals;

means for processing the plurality of uplink TPC streams to obtain a stream of joint power control commands for the data transmission; and

means for adjusting the transmit power of the data transmission based on the stream of joint power control commands.

36. An apparatus in a wireless communication system, comprising:

means for processing data for transmission to a plurality of terminals;

means for broadcasting the processed data on a first physical channel to the plurality of terminals; and

means for broadcasting control information on a second physical channel to the plurality of terminals, wherein the control information is used by the terminals to receive the data broadcasted on the first physical channel.