Methods for seamless delivery of broadcast and multicast content across cell borders and/or between different transmission schemes and related apparatus

• US 20050169205A1
• Filed: 08/19/2004
• Published: 08/04/2005
• Est. Priority Date: 08/21/2003
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Casaccia, Lorenzo, Grilli, Francesco, Vayanos, Alkinoos Hector
• Granted Patent: US 8,804,761 B2
• Time in Patent Office: Days
• US Class Current: 370/313
• 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 13/2703 the interleaver involving at least two directions
• CPC Class Codes: H03M 13/2915 with an error detection code in one dimension
• 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: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/0083 Formatting with frames or packets; Protocol or part of protocol for error control
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint

Abstract

Transmission techniques are provided that improve service continuity and reduce interruptions in delivery of content that can be caused by transitions that occur when the User Equipment (UE) moves from one cell to the other, or when the delivery of content changes from a Point-to-Point (PTP) connection to a Point-to-Multipoint (PTM) connection in the same serving cell, and vice-versa. Such transmission techniques enable seamless delivery of content across cell borders and/or between different transmission schemes such as Point-to-Multipoint (PTM) and Point-to-Point (PTP). Mechanisms for adjusting different streams and for recovering content from each data block during such transitions are also provided so that data is not lost during a transition. In addition, mechanisms for realigning data during decoding at a receiving terminal are also provided.

Claims

1. A method of communicating information over a channel, comprising:

framing rows of a first-type of information comprising payload data in a first format over a radio bearer from a first source to generate rows of a second-type of information;

encoding rows of the second-type of information to generate rows of redundancy information comprising parity blocks;

appending the rows of redundancy information to the rows of second-type information to produce an outer code block that comprises rows of the payload data in the second format and the parity blocks;

adding overhead information to each row of the outer code block, wherein the overhead information includes a sequence number; and

transmitting the outer code block to a radio link control layer.

2. A method according to claim 1, further comprising:

receiving the outer code block from the first source.

3. A method according to claim 2, further comprising:

receiving a second packet from a second source that is identical to the rows of second-type information when a wireless communicator undergoes a transition; and

using the sequence number to realign the outer code block with the second packet

4. A method according to claim 1, wherein the second-type of information comprises payload data in a second format and in some cases padding information.

5. A method according to claim 1, wherein the sequence number provided before encoding allows the radio link control layer to change modes when a wireless communicator undergoes a transition.

6. A method according to claim 1, wherein the encoding comprises outer-encoding and is performed independent of the radio link control layer.

7. A method according to claim 1, wherein the channel is a unidirectional, common logical channel.

8. A method according to claim 7, wherein the channel is a unidirectional downlink channel.

9. A method according to claim 8, wherein the common logical channel carries information that is broadcast to one or more terminals.

10. A method of transmitting a first outer code block and a second outer code block to a wireless communicator, comprising:

transmitting the first block, wherein the first block has at least one data row and at least one redundancy row, and wherein the each row has a overhead information that includes a sequence number, wherein the second block consists of only data rows; and

when the wireless communicator undergoes a transition, using the sequence number to align the first block with the second block.

11. A protocol structure for a communication system, comprising:

a radio link control layer; and

a forward error correction layer disposed above the radio link control layer,

wherein the forward error correction layer receives a first-type of information over a radio bearer before the first-type of information reaches the radio link control layer,

wherein the forward error correction layer frames the first-type of information into equal size frames before the first-type of information reaches the radio link control layer to generate a second-type of information,

wherein the forward error correction layer uses the second-type of information to generate rows of redundancy information that are added to the second-type of information to generate an outer code block,

wherein the forward error correction layer adds a sequence number to each frame, before transmitting to the radio link control layer.

12. A protocol structure according to claim 11, wherein the source is a first source, and wherein the outer code block is transmitted over a common logical channel.

13. A protocol structure according to claim 12, wherein the sequence number allows second type of information to be realigned, during a transition, with another second-type of information from a second source.

14. A method of encoding information before transmitting the information on a common channel in a system that includes a radio link control layer, comprising:

receiving the information from a radio bearer; and

outer block coding the information before passing the information to a radio link control layer.

15. A method according to claim 14, wherein the information comprises content and wherein outer block coding, comprises:

organizing the content into data blocks;

encoding the data blocks to generate parity blocks; and

adding the parity blocks to the data blocks to produce an encoder packet, wherein the parity blocks are configured to be used to reconstruct any data blocks lost during transmission.

16. A method according to claim 15, further comprising:

adding overhead information to each block in the encoder packet that identifies that block by a sequence number that includes an inner block number and an outer block number.

17. A method according to claim 15, wherein each block is transmitted in a single frame.

18. A method according to claim 15, wherein each block is transmitted in a plurality of frames.