Apparatus and method for transmitting/receiving a downlink signal in a communication system

• US 20070115890A1
• Filed: 11/20/2006
• Published: 05/24/2007
• Est. Priority Date: 11/18/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Hwang, In-Seok, Yoon, Soon-Young, Cho, Jae-Hee, Yi, Byoung-Ha, Jeong, Joong-Ho
• Granted Patent: US 7,715,361 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

In a communication system, a first Downlink (DL) signal to be commonly received by all Mobile Stations (MSs) at a Base Station (BS) is generated. A second DL signal that all the MSs do not need to commonly receive is generated. The first DL signal is applied to an interference cancellation scheme. The first DL signal is transmitted in a first time interval. The second DL signal is transmitted in a second time interval.

Claims

1. A method for transmitting a Downlink (DL) signal from a Base Station (BS) in a communication system, comprising:

generating a first DL signal to be commonly received by all Mobile Stations (MSs) at the BS and a second DL signal that all the MSs do not need to commonly receive;

transmitting the first DL signal in a first time interval by applying the first DL signal to an interference cancellation scheme; and

transmitting the second DL signal in a second time interval.

2. The method of claim 1, wherein the first time interval is prior to the second time interval.

3. The method of claim 1, wherein the first downlink signal comprises a frame control header, a MAP message and a common control message.

4. The method of claim 3, wherein generating the first DL signal further comprises generating the MAP message with a size equal to that of a MAP message to be commonly received by all MSs at a neighbor BS using the same frequency resources as the BS.

5. The method of claim 4, wherein generating the MAP message with the size equal to that of the MAP message of the neighbor BS further comprises padding zero in a field other than the MAP message in a preset size when the size of the MAP message is less than the preset size.

6. The method of claim 4, wherein generating the MAP message with the size equal to that of the MAP message of the neighbor BS further comprises performing a control operation such that no signal is transmitted in a field other than the MAP message in a preset size when the size of the MAP message is less than the preset size.

7. The method of claim 3, wherein generating the first DL signal further comprises concatenating multiple common control messages when a size of the common control message is less than a preset size.

8. The method of claim 3, wherein generating the first DL signal further comprises fragmenting the common control message into multiple common control message parts such that the common control message is fragmented and transmitted in first time intervals of current and next times when a size of the common control message is greater than a preset size.

9. The method of claim 1, wherein the second DL signal comprises a dedicated control message and traffic data.

10. The method of claim 9, wherein transmitting the dedicated control message in the second time interval further comprises the steps of:

setting a Modulation and Coding Scheme (MCS) level to be applied to the dedicated control message using performance of a link generated on a basis of an average Channel Quality Indication (CQI) of an MS corresponding to a target of the dedicated control message; and

modulating, encoding and transmitting the dedicated control message at the set MCS level.

11. The method of claim 9, wherein transmitting the traffic data in the second time interval further comprises:

setting a Modulation and Coding Scheme (MCS) level to be applied to the traffic data using performance of a link generated on a basis of a short-term Channel Quality Indication (CQI) of an MS corresponding to a target of the traffic data; and

modulating, encoding and transmitting the traffic data at the set MCS level.

12. A method for transmitting a Downlink (DL) signal from a Base Station (BS) in a communication system, comprising:

(a) adding a DL MAP information element to be periodically transmitted in a DL MAP message;

(b) performing an Uplink (UL) scheduling process and generating a UL MAP message reflecting a UL scheduling result;

(c) scheduling a common control message;

(d) scheduling a dedicated burst signal that all Mobile Stations (MSs) at the BS do not need to receive;

(e) adding scheduling information to the DL MAP message on a basis of a dedicated burst signal scheduling result;

(f) repeating steps (d) and (e) until DL resources to be additionally allocated are not present;

(g) transmitting the DL MAP message, the UL MAP message and the common control message in a first time interval by applying the DL MAP message, the UL MAP message and the common control message to an interference cancellation scheme; and

(h) transmitting the dedicated burst signal in a second time interval.

13. The method of claim 12, wherein generating the DL and UL MAP messages further comprises generating a MAP message corresponding to a sum of the DL and UL MAP messages with a size equal to that of a MAP message corresponding to a sum of DL and UL MAP messages of a neighbor BS using the same frequency resources as the BS.

14. The method of claim 13, wherein generating the MAP message with the size equal to that of the MAP message of the neighbor BS further comprises padding zero in a field other than the MAP message in a preset size when the size of the MAP message is less than the preset size.

15. The method of claim 13, wherein generating the MAP message with the size equal to that of the MAP message of the neighbor BS further comprises performing a control operation such that no signal is transmitted in a field other than the MAP message in a preset size when the size of the MAP message is less than the preset size.

16. The method of claim 12, wherein step (c) further comprises concatenating multiple common control messages when a size of the common control message is less than a preset size.

17. The method of claim 12, wherein step (c) further comprises fragmenting the common control message into multiple common control message parts such that the common control message is fragmented and transmitted in first time intervals of current and next times when a size of the common control message is greater than a preset size.

18. The method of claim 12, wherein step (d) further comprises

scheduling a dedicated control message;

and

scheduling traffic data.

19. The method of claim 18, wherein scheduling the dedicated control message further comprises setting a Modulation and Coding Scheme (MCS) level to be applied to the dedicated control message using performance of a link generated on a basis of an average Channel Quality Indication (CQI) of an MS corresponding to a target of the dedicated control message.

20. The method of claim 18, wherein scheduling the traffic data further comprises setting a Modulation and Coding Scheme (MCS) level to be applied to the traffic data using performance of a link generated on a basis of a short-term Channel Quality Indication (CQI) of an MS corresponding to a target of the traffic data.

21. The method of claim 12, wherein the first time interval is prior to the second time interval.

22. An apparatus for transmitting a Downlink (DL) signal from a Base Station (BS) in a communication system, comprising:

a scheduler for scheduling a first DL signal to be commonly received by all Mobile Stations (MSs) at the BS and a second DL signal that all the MSs do not need to commonly receive; and

a transmitter for transmitting the first DL signal in a first time interval by applying the first DL signal to an interference cancellation scheme, and transmitting the second DL signal in a second time interval.

23. The apparatus of claim 22, wherein the first time interval is prior to the second time interval.

24. The apparatus of claim 22, wherein the first downlink signal comprises a frame control header, a MAP message and a common control message.

25. The apparatus of claim 24, wherein the scheduler performs a scheduling process such that a size of the MAP message is equal to that of a MAP message to be commonly received by all MSs at a neighbor BS using the same frequency resources as the BS.

26. The apparatus of claim 24, wherein the scheduler performs a scheduling process such that zero is padded in a field other than the MAP message in a preset size when a size of the MAP message is less than the preset size.

27. The apparatus of claim 25, wherein the scheduler performs a scheduling process such that no signal is transmitted in a field other than the MAP message in a preset size when the size of the MAP message is less than the preset size.

28. The apparatus of claim 24, wherein the scheduler performs a scheduling process such that multiple common control messages are concatenated and transmitted when a size of the common control message is less than a preset size.

29. The apparatus of claim 24, wherein the scheduler performs a scheduling process such that the common control message is fragmented and transmitted in first time intervals of current and next times when a size of the common control message is greater than a preset size.

30. The apparatus of claim 22, wherein the second DL signal comprises a dedicated control message and traffic data.

31. The apparatus of claim 30, wherein the scheduler sets a Modulation and Coding Scheme (MCS) level to be applied to the dedicated control message using performance of a link generated on a basis of an average Channel Quality Indication (CQI) of an MS corresponding to a target of the dedicated control message.

32. The apparatus of claim 30, wherein the scheduler sets a Modulation and Coding Scheme (MCS) level to be applied to the traffic data using performance of a link generated on a basis of a short-term Channel Quality Indication (CQI) of an MS corresponding to a target of the traffic data.

33. An apparatus for transmitting a Downlink (DL) signal from a Base Station (BS) in a communication system, comprising:

a scheduler for adding a DL MAP information element to be periodically transmitted in a DL MAP message,

performing an Uplink (UL) scheduling process and generating a UL MAP message reflecting a UL scheduling result,

scheduling a common control message,

scheduling a dedicated burst signal that all Mobile Stations (MSs) at the BS do not need to receive,

adding scheduling information to the DL MAP message on a basis of a dedicated burst signal scheduling result, and

repeating an operation for scheduling the dedicated burst signal and adding the scheduling information to the DL MAP message on the basis of the dedicated burst signal scheduling result until DL resources to be additionally allocated are not present; and

a transmitter for transmitting the DL MAP message, the UL MAP message and the common control message in a first time interval by applying the DL MAP message, the UL MAP message and the common control message to an interference cancellation scheme, and transmitting the dedicated burst signal in a second time interval.

34. The apparatus of claim 33, wherein the scheduler performs a scheduling process such that a size of a MAP message corresponding to a sum of the DL and UL MAP messages is equal to that of a MAP message corresponding to a sum of DL and UL MAP messages of a neighbor BS using the same frequency resources as the BS.

35. The apparatus of claim 34, wherein the scheduler performs a scheduling process such that zero is padded in a field other than the MAP message in a preset size when the size of the MAP message is less than the preset size.

36. The apparatus of claim 34, wherein the scheduler performs a scheduling process such that no signal is transmitted in a field other than the MAP message in a preset size when the size of the MAP message is less than the preset size.

37. The apparatus of claim 33, wherein the scheduler performs a scheduling process such that multiple common control messages are concatenated and transmitted when a size of the common control message is less than a preset size.

38. The apparatus of claim 33, wherein the scheduler performs a scheduling process such that the common control message is fragmented and transmitted in first time intervals of current and next times when a size of the common control message is greater than a preset size.

39. The apparatus of claim 33, wherein the dedicated burst signal comprises a dedicated control message and traffic data.

40. The apparatus of claim 39, wherein the scheduler sets a Modulation and Coding Scheme (MCS) level to be applied to the dedicated control message using performance of a link generated on a basis of an average Channel Quality Indication (CQI) of an MS corresponding to a target of the dedicated control message.

41. The apparatus of claim 39, wherein the scheduler sets a Modulation and Coding Scheme (MCS) level to be applied to the traffic data using performance of a link generated on a basis of a short-term Channel Quality Indication (CQI) of an MS corresponding to a target of the traffic data.

42. The apparatus of claim 33, wherein the first time interval is prior to the second time interval.