METHODS FOR TRANSMITTING AND RECEIVING CONTROL CHANNEL, BASE STATION, AND USER EQUIPMENT

• US 20140321399A1
• Filed: 07/09/2014
• Published: 10/30/2014
• Est. Priority Date: 01/09/2012
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Liu, Kunpeng, Li, Chaojun, Wu, Qiang
• Granted Patent: US 9,426,796 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

Embodiments of the present invention provide methods for transmitting and receiving a control channel, a base station, and a user equipment, which relate to the communication field, and can solve a transmission problem of available changing transmission resources caused by introduction of an E-PDCCH. A method for configuring a control channel resource includes: determining, by a base station according to a system configuration and/or user configuration, resource elements REs included in an extended control channel element E-CCE, and transmitting an extended physical downlink control channel E-PDCCH to a user equipment, where the E-PDCCH is carried by the E-CCE; and receiving, by the user equipment, the E-PDCCH, and obtaining the REs included in the E-CCE, and receiving, over the REs included in the E-CCE, the E-PDCCH transmitted by the base station. The embodiments of the present invention are used for configuring and detecting a control channel resource.

Claims

1. A method for transmitting a control channel, the method comprising:

determining, according to a system configuration and/or user configuration, resource elements REs comprised in an extended control channel element E-CCE; and

transmitting an extended physical downlink control channel E-PDCCH to a user equipment, wherein the E-PDCCH is carried by the E-CCE.

2. The method according to claim 1, wherein determining, according to a system configuration and/or user configuration, resource elements REs comprised in an extended control channel element E-CCE comprises:

determining, according to resource elements REs comprised in a resource set and REs of predetermined overheads in the resource set, resource elements REs comprised in an extended control channel element E-CCE.

3. The method according to claim 2, wherein determining, according to resource elements REs comprised in a resource set and REs of predetermined overheads in the resource set, REs comprised in an extended control channel element E-CCE comprises:

obtaining, according to the number of REs comprised in a resource set and the number of REs of predetermined overheads in the resource set, the number of available REs in the resource set;

obtaining, according to the number of available REs in the resource set and the number of REs of predetermined overheads in the resource set, the number of REs available for each E-CCE; and

determining, according to the number of REs available for each E-CCE, the number of REs comprised in each E-CCE.

4. The method according to claim 2, wherein determining, according to resource elements REs comprised in a resource set and REs of predetermined overheads in the resource set, resource elements REs comprised in an extended control channel element E-CCE comprises:

dividing a resource set according to the predetermined number of E-CCEs in the resource set to obtain resource subsets;

obtaining, according to the number of REs comprised in each resource subset and the number of REs of predetermined overheads in each resource subset, the number of available REs in each resource set; and

determining, according to the number of available REs in each resource subset, the number of REs comprised in each E-CCE in the resource set.

5. The method according to claim 1, wherein determining, according to a system configuration and/or user configuration, resource elements REs comprised in an extended control channel element E-CCE comprises:

determining, according to at least one of a preset precoding resource block group PRG, a resource block group RBG, a system bandwidth, a configured control channel bandwidth, different aggregation levels, and different parameters of different E-CCEs at a same aggregation level, the number of REs comprised in the E-CCE.

6. The method according to claim 3, wherein determining, according to a system configuration and/or user configuration, resource elements REs comprised in an extended control channel element E-CCE comprises:

determining, according to the number of REs comprised in the E-CCE and a predetermined rule, the REs comprised in the E-CCE, wherein the REs comprised in the E-CCE do not comprise the REs of the predetermined overheads.

7. The method according to claim 6, wherein determining, according to the number of REs comprised in the E-CCE and a predetermined rule, the REs comprised in the E-CCE, wherein the REs comprised in the E-CCE do not comprise the REs of the predetermined overheads, comprises:

mapping, from a preset start point of the E-CCE, first in a frequency domain and then in a time domain, or first in a time domain and then in a frequency domain, the REs comprised in the E-CCE, wherein if REs occupied by the predetermined overheads exist during the mapping, the E-CCE is not mapped in RE positions occupied by the predetermined overheads, and the REs occupied by the predetermined overheads are correspondingly subtracted from the number of REs comprised in the E-CCE;

or skipping RE positions occupied by the predetermined overheads, and mapping the number of REs comprised in the E-CCE;

or mapping the number of REs comprised in the E-CCE from a preset start point of the E-CCE, wherein a control channel mapped to the REs occupied by the predetermined overheads is punched for transmitting the predetermined overheads.

8. The method according to claim 2, wherein the resource set is any one of a physical resource block PRB, a physical resource block pair, a precoding resource block group PRG, a resource block group RBG, and a set divided into various E-CCE resources.

9. The method according to claim 2, wherein the predetermined overheads comprise a pilot overhead and/or at least one of overheads of channels other than an E-PDCCH and a PDCCH.

10. The method according to claim 9, wherein the pilot overhead comprises at least one of a channel state indicator-pilot symbol CSI-RS, a cell pilot signal CRS, a demodulation pilot DMRS, and a muted RE, and the overheads of other channels comprise a paging channel or a synchronization channel.

11. The method according to claim 1, wherein the E-CCE comprises an E-CCE of a first type and/or an E-CCE of a second type, wherein REs comprised in the E-CCE of the first type are fixed, and REs comprised in the E-CCE of the second type change semi-statically or dynamically.

12. The method according to claim 11, wherein:

in a configured control channel region, the E-CCE of the first type or the E-CCE of the second type has an equal spacing between search start points or search spaces in the frequency domain, wherein the spacing is at least one subcarrier, or has an equal spacing between search start points or search spaces in the time domain, wherein the spacing is at least one orthogonal frequency division multiplexing OFDM symbol.

13. The method according to claim 11, wherein:

a search space of the E-CCE of the first type and a search space of the E-CCE of the second type are used by frequency division multiplexing or time division multiplexing in a precoding resource block group, a PRG, or an RBG, and E-CCEs of a same type in a same PRG have a same precoding vector.

14. The method according to claim. 11, wherein a demodulation pilot DMRS port of the E-CCE of the first type is fixed, and a demodulation pilot DMRS port of the E-CCE of the second type is dynamically changeable.

15. The method according to claim 11, wherein:

a common search space uses the E-CCE of the first type, and a user-specific search space uses the E-CCE of the second type;

or

E-CCEs using different resource mapping modes are respectively mapped to E-CCEs of different types, wherein, an E-CCE using discrete resource mapping is an E-CCE of the first type, and an E-CCE using centralized resource mapping is an E-CCE of the second type;

or

a common search space of an E-CCE carrying an E-PDCCH uses the E-CCE of the first type;

before a user equipment receives a CSI-RS configuration, a user-specific search space of the E-CCE carrying the E-PDCCH uses the E-CCE of the first type, and after the user equipment receives the CSI-RS configuration, the user-specific search space uses the E-CCE of the second type.

16. A method for receiving a control channel, the method comprising:

obtaining resource elements REs comprised in an extended control channel element E-CCE, wherein the REs comprised in the E-CCE are determined according to a system configuration and/or user configuration; and

receiving, over the REs comprised in the E-CCE, an extended physical downlink control channel E-PDCCH transmitted by a base station.

17. The method according to claim 16, wherein obtaining resource elements REs comprised in an extended control channel element E-CCE, wherein the REs comprised in the E-CCE are determined according to a system configuration and/or user configuration, comprises:

obtaining, according to resource elements REs comprised in a resource set and REs of predetermined overheads in the resource set, resource elements REs comprised in an extended control channel element E-CCE.

18. The method according to claim 17, wherein obtaining, according to resource elements REs comprised in a resource set and REs of predetermined overheads in the resource set, resource elements REs comprised in an extended control channel element E-CCE comprises:

obtaining, according to the number of REs comprised in a resource set and the number of REs of predetermined overheads in the resource set, the number of available REs in the resource set;

obtaining, according to the number of available REs in the resource set and the number of REs of predetermined overheads in the resource set, the number of REs available for each E-CCE; and

obtaining, according to the number of REs available for each E-CCE, the number of REs comprised in each E-CCE.

19. The method according to claim 17, wherein obtaining, according to resource elements REs comprised in a resource set and REs of predetermined overheads in the resource set, resource elements REs comprised in an extended control channel element E-CCE comprises:

dividing a resource set according to the predetermined number of E-CCEs in the resource set to obtain resource subsets;

obtaining, according to the number of REs comprised in each resource subset and the number of REs of predetermined overheads in each resource subset, the number of available REs in each resource set; and

obtaining, according to the number of available REs in each resource subset, the number of REs comprised in each E-CCE in the resource set.

20. The method according to claim 16, wherein obtaining resource elements REs comprised in an extended control channel element E-CCE, wherein the REs comprised in the E-CCE are determined according to a system configuration and/or user configuration, comprises:

obtaining, according to at least one of a preset precoding resource block group PRG, a resource block group RBG, a system bandwidth, a configured control channel bandwidth, different aggregation levels, and different parameters of different E-CCEs at a same aggregation level, the number of REs comprised in the E-CCE.

21. The method according to claim 18, wherein obtaining resource elements REs comprised in an extended control channel element E-CCE, wherein the REs comprised in the E-CCE are determined according to a system configuration and/or user configuration, comprises:

obtaining, according to the number of REs comprised in the E-CCE and a predetermined rule, the REs comprised in the E-CCE, wherein the REs comprised in the E-CCE do not comprise the REs of the predetermined overheads.

22. The method according to claim 21, wherein obtaining, according to the number of REs comprised in the E-CCE and a predetermined rule, the REs comprised in the E-CCE, wherein the REs comprised in the E-CCE do not comprise the REs of the predetermined overheads, comprises:

performing resource demapping, from a preset start point of the E-CCE, first in a frequency domain and then in a time domain, or first in a time domain and then in a frequency domain, for the REs comprised in the E-CCE;

if REs occupied by the predetermined overheads exist during the resource demapping, skipping RE positions occupied by the predetermined overheads and performing resource demapping, wherein the number of demapped symbols is the number of REs comprised in the E-CCE after the REs occupied by the predetermined overheads are correspondingly subtracted;

or if REs occupied by the predetermined overheads exist during the resource demapping, skipping RE positions occupied by the predetermined overheads, wherein the number of demapped symbols is the number of REs comprised in the E-CCE.

23. The method according to claim 17, wherein the resource set is any one of a physical resource block PRB, a physical resource block pair, a precoding resource block group PRG, a resource block group RBG, and a set divided into various E-CCE resources.

24. The method according to claim 17, wherein the predetermined overheads comprise a pilot overhead and/or at least one of overheads of channels other than an E-PDCCH and a PDCCH.

25. The method according to claim 24, wherein the pilot overhead comprises at least one of a channel state indicator-pilot symbol CSI-RS, a cell pilot signal CRS, a demodulation pilot DMRS, and a muted RE, and the overheads of other channels comprise a paging channel or a synchronization channel.

26. The method according to claim 16, wherein the E-CCE comprises an E-CCE of a first type and/or an E-CCE of a second type, wherein REs comprised in the E-CCE of the first type are fixed, and REs comprised in the E-CCE of the second type change semi-statically or dynamically.

27. The method according to claim 26, wherein:

in a configured control channel region, the E-CCE of the first type or the E-CCE of the second type has an equal spacing between search start points or search spaces in the frequency domain, wherein the spacing is at least one subcarrier, or has an equal spacing between search start points or search spaces in the time domain, wherein the spacing is at least one orthogonal frequency division multiplexing OFDM symbol.

28. The method according to claim 26, wherein:

a search space of the E-CCE of the first type and a search space of the E-CCE of the second type are used by frequency division multiplexing or time division multiplexing in a precoding block resource block group, a PRG, or an RBG, and E-CCEs of a same type in a same PRG have a same precoding vector for performing joint channel estimation.

29. The method according to claim 26, wherein a demodulation pilot DMRS port of the E-CCE of the first type is fixed, and a demodulation pilot DMRS port of the E-CCE of the second type is dynamically changeable.

30. The method according to claim 26, wherein:

the E-CCE of the first type is detected in a common search space, and the E-CCE of the second type is detected in a user-specific search space;

or

the E-CCE of the first type is detected in a common search space;

before a CSI-RS configuration or other RRC signaling is received, the E-CCE of the first type is detected in a user-specific search space according to the number of REs comprised in the E-CCE of the first type; and

after the CSI-RS configuration or other RRC signaling is received, the E-CCE of the second type is detected in the user-specific search space.

31. A base station, comprising:

a processing unit, configured to determine, according to a system configuration and/or user configuration, resource elements REs comprised in an extended control channel element E-CCE; and

a transmitting unit, configured to transmit an extended physical downlink control channel E-PDCCH to a user equipment, wherein the E-PDCCH is carried by the E-CCE.

32. The base station according to claim 31, wherein the processing unit comprises:

a setting module, configured to determine, according to resource elements REs comprised in a resource set and REs of predetermined overheads in the resource set, resource elements REs comprised in an extended control channel element E-CCE.

33. The base station according to claim 32, wherein the setting module is configured to:

obtain, according to the number of REs comprised in a resource set and the number of REs of predetermined overheads in the resource set, the number of available REs in the resource set;

obtain, according to the number of available REs in the resource set and the number of REs of predetermined overheads in the resource set, the number of REs available for each E-CCE; and

determine, according to the number of REs available for each E-CCE, the number of REs comprised in each E-CCE.

34. The base station according to claim 32, wherein the setting module is configured to:

divide a resource set according to the predetermined number of E-CCEs in the resource set to obtain resource subsets;

obtain, according to the number of REs comprised in each resource subset and the number of REs of predetermined overheads in each resource subset, the number of available REs in each resource set; and

determine, according to the number of available REs in each resource subset, the number of REs comprised in each E-CCE in the resource set.

35. The base station according to claim 31, wherein the processing unit comprises:

a setting module, configured to determine, according to at least one of a preset precoding resource block group PRG, a resource block group RBG, a system bandwidth, a configured control channel bandwidth, different aggregation levels, and different parameters of different E-CCEs at a same aggregation level, the number of REs comprised in the E-CCE.

36. The base station according to claim 33, wherein the setting module is further configured to:

determine, according to the number of REs comprised in the E-CCE and a predetermined rule, the REs comprised in the E-CCE, wherein the REs comprised in the E-CCE do not comprise the REs of the predetermined overheads.

37. The base station according to claim 36, wherein the processing unit comprises:

a mapping module, configured to;

map, from a preset start point of the E-CCE, first in a frequency domain and then in a time domain, or first in a time domain and then in a frequency domain, the REs comprised in the E-CCE, wherein if REs occupied by the predetermined overheads exist during the mapping, the E-CCE is not mapped in RE positions occupied by the predetermined overheads, and the REs occupied by the predetermined overheads are correspondingly subtracted from the number of REs comprised in the E-CCE;

or

skip RE positions occupied by the predetermined overheads, and map the number of REs comprised in the E-CCE;

or map the number of REs comprised in the E-CCE from a preset start point of the E-CCE, wherein a control channel mapped to the REs occupied by the predetermined overheads is punched for transmitting the predetermined overheads.

38. The base station according to claim 32, wherein the resource set is any one of a physical resource block PRB, a physical resource block pair, a precoding resource block group PRG, a resource block group RBG, and a set divided into various E-CCE resources.

39. The base station according to claim 32, wherein the predetermined overheads comprise a pilot overhead and/or at least one of overheads of channels other than an E-PDCCH and a PDCCH.

40. The base station according to claim 39, wherein the pilot overhead comprises at least one of a channel state indicator-pilot symbol CSI-RS, a cell pilot signal CRS, a demodulation pilot DMRS, and a muted RE, and the overheads of other channels comprise a paging channel or a synchronization channel.

41. The base station according to claim 31, wherein:

the processing unit is configured to process the E-CCE, wherein the E-CCE comprises an E-CCE of a first type and/or an E-CCE of a second type, wherein the number of REs comprised in the E-CCE of the first type is fixed on a first specific resource, and REs comprised in the E-CCE of the second type change semi-statically or dynamically on a second specific resource.

42. The base station according to claim 41, wherein, in a configured control channel region, the E-CCE of the first type or the E-CCE of the second type has an equal spacing between search start points or search spaces in the frequency domain, wherein the spacing is at least one subcarrier, or has an equal spacing between search start points or search spaces in the time domain, wherein the spacing is at least one orthogonal frequency division multiplexing OFDM symbol.

43. The base station according to claim 41, a search space of the E-CCE of the first type and a search space of the E-CCE of the second type are used by frequency division multiplexing or time division multiplexing in a precoding resource block group, a PRG, or an RBG, and E-CCEs of a same type in a same PRG have a same precoding vector.

44. The base station according to claim 41, wherein a demodulation pilot DMRS port of the E-CCE of the first type is fixed, and a demodulation pilot DMRS port of the E-CCE of the second type is dynamically changeable.

45. The base station according to claim 41, wherein:

a common search space uses the E-CCE of the first type, and a user-specific search space uses the E-CCE of the second type;

or

E-CCEs using different resource mapping modes are respectively mapped to E-CCEs of different types, wherein, an E-CCE using discrete resource mapping is an E-CCE of the first type, and an E-CCE using centralized resource mapping is an E-CCE of the second type;

or

a common search space of an E-CCE carrying an E-PDCCH uses the E-CCE of the first type;

before a user equipment receives a CSI-RS configuration, a user-specific search space of the E-CCE carrying the E-PDCCH uses the E-CCE of the first type, and after the user equipment receives the CSI-RS configuration, the user-specific search space uses the E-CCE of the second type.

46. A user equipment, comprising:

a processing unit, configured to obtain resource elements REs comprised in an extended control channel element E-CCE, wherein the REs comprised in the E-CCE are determined according to a system configuration and/or user configuration; and

a receiving unit, configured to receive, over the REs comprised in the E-CCE, an extended physical downlink control channel E-PDCCH transmitted by a base station.

47. The user equipment according to claim 46, wherein the processing unit comprises:

an obtaining module, configured to obtain, according to resource elements REs comprised in a resource set and REs of predetermined overheads in the resource set, resource elements REs comprised in an extended control channel element E-CCE.

48. The user equipment according to claim 47, wherein the processing unit is configured to:

obtain, according to the number of REs comprised in a resource set and the number of REs of predetermined overheads in the resource set, the number of available REs in the resource set;

obtain, according to the number of available REs in the resource set and the number of REs of predetermined overheads in the resource set, the number of REs available for each E-CCE; and

obtain, according to the number of REs available for each E-CCE, the number of REs comprised in each E-CCE.

49. The user equipment according to claim 47, wherein the processing unit is configured to:

divide a resource set according to the predetermined number of E-CCEs in the resource set to obtain resource subsets;

obtain, according to the number of REs comprised in each resource subset and the number of REs of predetermined overheads in each resource subset, the number of available REs in each resource set; and

obtain, according to the number of available REs in each resource subset, the number of REs comprised in each E-CCE in the resource set.

50. The user equipment according to claim 46, wherein the processing unit comprises:

a setting module, configured to obtain, according to at least one of a preset precoding resource block group PRG, a resource block group RBG, a system bandwidth, a configured control channel bandwidth, different aggregation levels, and different parameters of different E-CCEs at a same aggregation level, the number of REs comprised in the E-CCE.

51. The user equipment according to claim 48, wherein the processing unit is further configured to:

obtain, according to the number of REs comprised in the E-CCE and a predetermined rule, the REs comprised in the E-CCE, wherein the REs comprised in the E-CCE do not comprise the REs of the predetermined overheads.

52. The user equipment according to claim 51, wherein the processing unit comprises:

a resource demapping module, configured to;

perform resource demapping, from a preset start point of the E-CCE, first in a frequency domain and then in a time domain, or first in a time domain and then in a frequency domain, for the REs comprised in the E-CCE;

if REs occupied by the predetermined overheads exist during the resource demapping, skip RE positions occupied by the predetermined overheads and perform resource demapping, wherein the number of demapped symbols is the number of REs comprised in the E-CCE after the REs occupied by the predetermined overheads are correspondingly subtracted;

or

if REs occupied by the predetermined overheads exist during the resource demapping, skip RE positions occupied by the predetermined overheads, wherein the number of demapped symbols is the number of REs comprised in the E-CCE.

53. The user equipment according to claim 47, wherein the resource set is any one of a physical resource block PRB, a physical resource block pair, a precoding resource block group PRG, a resource block group RBG, and a set divided into various E-CCE resources.

54. The user equipment according to claim 47, wherein the predetermined overheads comprise a pilot overhead and/or at least one of overheads of channels other than an E-PDCCH and a PDCCH.

55. The user equipment according to claim 54, wherein the pilot overhead comprises at least one of a channel state indicator-pilot symbol CSI-RS, a cell pilot signal CRS, a demodulation pilot DMRS, and a muted RE, and the overheads of other channels comprise a paging channel or a synchronization channel.

56. The user equipment according to claim 46, wherein:

the processing unit is configured to process the E-CCE, wherein the E-CCE comprises an E-CCE of a first type and/or an E-CCE of a second type, wherein the number of REs comprised in the E-CCE of the first type is fixed on a first specific resource, and REs comprised in the E-CCE of the second type change semi-statically or dynamically on a second specific resource.

57. The user equipment according to claim 56, wherein:

in a configured control channel region, the E-CCE of the first type or the E-CCE of the second type has an equal spacing between search start points or search spaces in the frequency domain, wherein the spacing is at least one subcarrier, or has an equal spacing between search start points or search spaces in the time domain, wherein the spacing is at least one orthogonal frequency division multiplexing OFDM symbol.

58. The user equipment according to claim 56, wherein:

a search space of the E-CCE of the first type and a search space of the E-CCE of the second type are used by frequency division multiplexing or time division multiplexing in a precoding block resource block group, a PRG, or an RBG, and E-CCEs of a same type in a same PRG have a same precoding vector for performing joint channel estimation.

59. The user equipment according to claim 56, wherein a demodulation pilot DMRS port of the E-CCE of the first type is fixed, and a demodulation pilot DMRS port of the E-CCE of the second type is dynamically changeable.

60. The user equipment according to claim 56, wherein:

the E-CCE of the first type is detected in a common search space, and the E-CCE of the second type is detected in a user-specific search space;

or

the E-CCE of the first type is detected in a common search space;

before a CSI-RS configuration or other RRC signaling is received, the E-CCE of the first type is detected in a user-specific search space according to the number of REs comprised in the E-CCE of the first type; and

after the CSI-RS configuration or other RRC signaling is received, the E-CCE of the second type is detected in the user-specific search space.