Method for transmitting and receiving data

• US 20060193351A1
• Filed: 02/01/2006
• Published: 08/31/2006
• Est. Priority Date: 02/02/2005
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Sang-Gook, Kim, Young-Jun, Kim, Ki-Jun, Kyung, Chan-Ho, An, Jong-Hoe, Kwon, Soon-Yil, Yun, Young-Woo
• Granted Patent: US 7,653,027 B2
• Time in Patent Office: Days
• US Class Current: 370/538
• CPC Class Codes: H04B 7/2656 for structure of frame, burst
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0006 by adapting the transmission format
• CPC Class Codes: H04L 1/1819 with retransmission of additional or different redundancy
• CPC Class Codes: H04L 1/1845 Combining techniques, e.g. code combining
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint

Abstract

In a mobile communications system, a method of transmitting data corresponding to the same logical channel through two or more base stations, comprising: transmitting a first sub-packet generated by a first base station and a second base station based upon an encoded packet; and at a time point after the lapse of a certain time period from when the first sub-packet was transmitted, transmitting a second sub-packet generated by one of the first and second base stations based upon the encoded packet. When data corresponding to the same logical channel is broadcast from each base station that has respectively different channel environments, data transmission efficiency can be improved.

Claims

1. A point-to-multipoint service method for a communications system having at least one access network and multiple terminals, the method comprising:

configuring the access network such that sectors in the same zone transmitting the same logical channel are allowed to employ different transmit data rates for transmitting data packets; and

providing the point-to-multipoint service to respective terminals using the different transmit data rates.

2. The method of claim 1, wherein the configuring step comprises:

employing transmission formats associated with the different transmit data rates, wherein the transmission formats are rate-compatible with one another.

3. The method of claim 2, wherein the different transmit data rates are based upon respective channel conditions of each sector.

4. The method of claim 3, wherein the access network comprises one or more base stations related to each sector.

5. The method of claim 3, wherein each sector is related to a base station or a cell.

6. The method of claim 2, wherein the providing step comprises:

transmitting packets using a transmission format with slots, wherein a transmission time of a first slot of each packet are synchronized across all sectors that transmit the same logical channel.

7. The method of claim 6, wherein one sector employs a transmission format with a span of one slot, while other sectors employ a rate compatible transmission format with a span of three slots.

8. The method of claim 6, wherein one sector employs a transmission format with a span having a first number of slots, while other sectors employ a rate compatible transmission format with a span having a second number of slots.

9. The method of claim 8, wherein the first and second numbers of slots may be the same or may be different.

10. The method of claim 1, wherein the providing step comprises:

sending a broadcast overhead message that specifies a transmission format used by a representative sector.

11. The method of claim 10, wherein the transmission format employs a field used to indicate a period, wherein the period refers to the number of slots between successive transmissions of packets on a given interlace-multiplex pair.

12. The method of claim 11, wherein a value of the field is greater than or equal to the span of the transmission format.

13. The method of claim 11, wherein at least one remaining slot of a period associated with the one sector is employed for unicast transmission.

14. The method of claim 1, wherein the configuring step comprises:

independently assigning a variable transmit data rate to one or more base stations of the adjacent sectors according to channel conditions of each base station.

15. A point-to-multipoint service method for a communications system having at least one access network and multiple terminals, the method comprising:

configuring the access network such that sectors of the same zone form a certain number of sub-packets associated with a single packet; and

transmitting from each sector, the certain number of sub-packets which are associated with the single packet, wherein the certain number of sub-packets are independently determined by each sector.

16. The method of claim 15, wherein the sub-packets are transmitted at a constant interval.

17. The method of claim 16, wherein if one sector transmits less than a maximum number of sub-packets during a given time interval, one or more sub-packets unrelated to the single packet are transmitted by the one sector.

18. The method of claim 17, wherein the maximum number is based upon a transmission capability of a worst sector.

19. The method of claim 17, wherein the one sector transmits less than the maximum number of sub-packets means that the one sector transmits less number of sub-packets than at least one different sector.

20. The method of claim 17, wherein the unrelated sub-packets are transmitted during the given time interval upon being scheduled in the slots where additional sub-packets related to the single packet would have been scheduled.

21. The method of claim 17, wherein the unrelated sub-packets replace additional sub-packets of the single packet that would have been transmitted during the given time interval.

22. The method of claim 15, wherein the configuring step employs transmission formats associated with the different transmit data rates, wherein the transmission formats are rate-compatible with one another, and the different transmit data rates are based upon respective channel conditions of each sector.

23. The method of claim 15, wherein the transmitting step employs a transmission format with slots, wherein a transmission time of a first slot of each packet are synchronized across all sectors that transmit the same logical channel.

24. The method of claim 23, wherein one sector employs a transmission format with a span of one slot, while other sectors employ a rate compatible transmission format with a span of three slots.

25. The method of claim 24, wherein the transmission format employs a field used to indicate a period, wherein the period refers to the number of slots between successive transmissions of packets on a given interlace-multiplex pair.

26. The method of claim 25, wherein a value of the field is greater than or equal to the span of the transmission format.

27. The method of claim 15, wherein the number of sub-packets transmitted from at least two different sectors are different or are the same.

28. A terminal supporting a point-to-multipoint service and communicating with an access network, the terminal comprising:

a transceiver to receive from one or more cells, a certain number of sub-packets associated with one particular packet, whereby the same sub-packet is received from two or more cells if necessary, each cell transmitting one or more sub-packets during a certain time period; and

a processor cooperating with the transceiver to perform soft combining of the same sub-packets received from two or more cells via the transceiver.

29. The terminal of claim 28, wherein the certain number of sub-packets associated with the one particular packet were made by the access network that was configured such that cells of the same zone make the certain number of sub-packets, wherein the certain number of sub-packets were independently determined by each cell.

30. The terminal of claim 28, wherein among the cells that transmit the sub-packets, a worst cell having the most poor channel conditions transmits multiple sub-packets during the certain time period.

31. The terminal of claim 30, wherein cells other than the worst cell are allowed to transmit data unrelated to the one particular packet during the certain time period while the worst cell transmits its multiple sub-packets.

32. The terminal of claim 31, wherein the data is received in a unicast manner and is related to FTP downloading.

33. The terminal of claim 28, wherein the cells are associated with base stations, and the transceiver and processor further cooperate such that,

the transceiver receives one or more initial sub-packets related to a single packet from a initial number of base stations associated with soft combining, and receives one or more additional sub-packets related to the single packet from an additional number of base stations associated with soft combining;

and

the processor decodes the sub-packets received from the base stations upon performing soft combining thereon,

wherein the initial number of base stations and the additional number of base stations are flexibly adjusted based upon respective channel conditions.

34. The terminal of claim 28, wherein the transceiver and processor further cooperate to receive, from a serving base station, a broadcast overhead message that includes information about how many sub-packets are transmitted from each of the base stations associated with soft combining.

35. A method of receiving a point-to-multipoint service by a terminal in communication with multiple base stations including a serving base station and neighbor base stations, the method comprising:

receiving one or more first sub-packets related to a single packet from a first number of base stations associated with soft combining;

receiving one or more second sub-packets related to the single packet from a second number of base stations associated with soft combining; and

decoding the sub-packets received from the base stations upon performing soft combining thereto,

wherein the first number of base stations and the second number of base stations are variable based upon channel conditions of the corresponding base stations.

36. The method of claim 35, further comprising a step of:

receiving one or more n^th sub-packets related to the single packet from an n-number of base stations associated with soft combining, wherein the first, the second, and the n-number of base stations are variable based upon channel conditions of the corresponding base stations.

37. The method claim 35, further comprising, prior to the receiving steps:

receiving, from the serving base station, a broadcast overhead message that includes information about how many sub-packets are transmitted from each of the base stations associated with soft combining.

38. The method claim 37, further comprising:

preparing to receive unicast data transmitted from the serving base station through any remaining slots, if the serving base station sends a smaller number of sub-packets than other neighbor base stations.