Interference Control in HETNETs

Patent metadata

Field	Value
Publication number	US-2016007361-A1
Application number	US-201214412596-A
Country	US
Kind code	A1
Filing date	Jul 4, 2012
Priority date	Jul 4, 2012
Publication date	Jan 7, 2016
Grant date	—

Abstract

The embodiments herein relates to a method in a first base station ( 201 a ) for controlling interference on a second Physical Downlink Control CHannel, PDCCH ( 210 b ). The second PDCCH ( 210 b ) is between a second base station ( 201 b ) and a second user equipment ( 205 b ). The first base station ( 201 a ) receives ( 602 ), from the second base station ( 201 b ), coordination information associated with the second PDCCH ( 210 b ). Based on the received coordination information, the first base station ( 201 a ) controls ( 306, 405, 503, 505, 507, 603 ) the interference on the second PDCCH ( 210 b ), wherein the interference is caused by a first PDCCH ( 210 a ) from the first base station ( 201 a ) to a first user equipment ( 205 a ).

First claim

1 - 38 . (canceled)

39 . A method in a first base station for controlling interference on a second Physical Downlink Control CHannel (PDCCH), which second PDCCH is between a second base station and a second user equipment, the method comprising:
receiving, from the second base station, coordination information associated with the second PDCCH; and based on the received coordination information, controlling the interference on the second PDCCH, wherein the interference is caused by a first PDCCH from the first base station to a first user equipment.

40 . The method of claim 39 , wherein controlling the interference comprises performing link adaptation of the first PDCCH, and wherein the method further comprises transmitting downlink control information to the first user equipment based on the performed link adaptation of the first PDCCH.

41 . The method of claim 40 , wherein the controlling the interference further comprises setting a Control Format Indicator (CFI) to a first value, and wherein the link adaptation is performed when the first base station is configured to schedule an uplink grant and/or a downlink assignment and/or a uplink transmission power control command to the first user equipment, which scheduling is based on the CFI.

42 . The method of claim 40 , wherein the link adaptation is further based on an adjustment offset.

43 . The method of claim 42 , wherein the adjustment offset is associated with at least one of a number of Control Channel Elements (CCEs) and a Signal to Interference plus Noise Ratio (SINR).

44 . The method of claim 42 , wherein the adjustment offset is fixed or wherein the adjustment offset is dynamic and varying in different subframes.

45 . The method of claim 40 , wherein the first value corresponds to a minimum number of Orthogonal Frequency Division Multiplexing (OFDM) symbols for the first PDCCH.

46 . The method of claim 40 , wherein the first value corresponds to a maximum number of Orthogonal Frequency Division Multiplexing (OFDM) symbols for the PDCCH.

47 . The method of claim 40 , wherein the CFI is set to the first value when a subframe in which the first base station is configured to transmit to the first user equipment on the first PDCCH is a Protected SubFrame (PSF).

48 . The method of claim 40 , wherein the CFI is set to the first value when a subframe in which the first base station is configured to transmit to the first user equipment on the first PDCCH is the subframe in which the second PDCCH is sensitive to interference, which interference is caused by the first transmission from the first base station on the first PDCCH to the first user equipment.

49 . The method of claim 39 , wherein controlling the interference further comprises:
determining a number of Control Channel Elements (CCEs); and transmitting downlink control information to the first user equipment on the first PDCCH, wherein the first PDCCH is transmitted on CCEs comprised in the determined number of CCEs.

50 . The method of claim 49 , wherein the number of CCEs is lower than or equal to a total number of available CCEs.

51 . The method of claim 49 , wherein the total number of available CCEs is dependent on at least one of a system bandwidth, a Control Format Indicator (CFI) configured cyclic prefix, and information about a Physical Hybrid automatic repeat request Indicator Channel (PHICH) configuration.

52 . The method of claim 39 , wherein the coordination information received from the second base station comprises information about a configuration of the second PDCCH, and wherein the method further comprises transmitting, to the second base station, coordination information associated with the first PDCCH between the first base station and the first user equipment.

53 . The method of claim 52 , wherein the coordination information received from the second base station and the coordination information transmitted to the second base station each comprises at least one of a cell index, a number of resource blocks, a number of sub-carriers per resource block, a number of antenna ports at the first base station, a Control Format Indicator (CFI), a cyclic prefix, a Physical Hybrid Automatic Repeat-reQuest Indicator Channel (PHICH) duration, a PHICH nG factor, and a duplex mode.

54 . The method of claim 39 , wherein the first base station is a macro base station and the second base station is a micro base station, or wherein the first base station is a micro base station and the second base station is a macro base station.

55 . The method of claim 39 , wherein controlling interference on the second PDCCH comprises based on the received coordination information, reducing the interference on the second PDCCH or avoiding the interference on the second PDCCH.

56 . The method of claim 39 , wherein the first user equipment comprises one first user equipment or a plurality of first user equipments.

57 . The method of claim 39 , wherein the interference is further caused by a first Physical Downlink Shared Channel (PDSCH) from the first base station to a first user equipment, and wherein the interference on the second PDCCH is controlled by restricting the transmission of the first PDSCH on the bandwidth or by transmitting the first PDSCH with a reduced power.

58 . A first base station for controlling interference on a second Physical Downlink Control CHannel (PDCCH), which second PDCCH is between a second base station and a second user equipment, the first base station comprising:
a receiver configured to receive, from the second base station, coordination information associated with the second PDCCH; and a processor configured to, based on the received coordination information, control the interference on the second PDCCH, wherein the interference is caused by a first PDCCH from the first base station to a first user equipment.

59 . The first base station of claim 58 , wherein the processor is further configured to:
perform link adaptation of the first PDCCH based on the CFI; and wherein the first base station further comprises: a transmitter configured to transmit downlink control information to the first user equipment based on the performed link adaptation of the first PDCCH.

60 . The first base station of claim 59 , wherein the processor is configured to:
set a Control Format Indicator (CFI) to a first value; and perform the link adaptation when the first base station is configured to schedule an uplink grant and/or a downlink assignment and/or an uplink transmission power control command to the first user equipment, which scheduling is based on the CFI.

61 . The first base station of claim 59 , wherein the link adaptation is further based on an adjustment offset.

62 . The first base station of claim 61 , wherein the adjustment offset is associated with at least one of a number of Control Channel Element (CCEs) and a Signal to Interference plus Noise Ratio (SINR).

63 . The first base station of claim 61 , wherein the adjustment offset is fixed or wherein the adjustment offset is dynamic and varying in different subframes.

64 . The first base station of claim 59 , wherein the first value corresponds to a minimum number of Orthogonal Frequency Division Multiplexing (OFDM) symbols for the first PDCCH.

65 . The first base station of claim 59 , wherein the first value corresponds to a maximum number of Ortho

Assignees

• Andersson Håkan
• Fröberg Olsson Jonas
• Rosin Olle
• Ericsson Telefon Ab L M

Inventors

• Andersson Håkan
• Fröberg Olsson Jonas
• Rosin Olle

Classifications

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04W72/541 Primary

  using the level of interference · CPC title

• H04W72/082 Primary

  Electricity · mapped topic

• H04W72/042

  Electricity · mapped topic

• H04L5/0073

  Allocation arrangements that take into account other cell interferences · CPC title