Method for transmitting support information for removing interference of terminal, and serving cell base station
One embodiment of the present specification discloses a method by which a serving cell transmits support information for removing interference of a terminal. The method comprises: a step for determining, by the serving cell, a downlink timing offset with neighboring interference cells; and a step for to determining, by the serving cell, a channel corresponding to an interference removal target among neighboring interference cells according to the timing offset. Here, the channel to have interference removed can be the channel interfering in a control channel for the serving cell according to the timing offset. The method further includes a step for enabling the serving cell to generate the interference removal support information on the determined channel and transmit the generated information to a terminal.
1. A method for transmitting assistance information for interference cancellation for a user equipment, the method comprising:
determining, by a serving cell, a downlink timing offset with a neighbor interfering cell;
selecting, by the serving cell, a channel which is subjected to an interference cancellation among channels of the neighbor interfering cell based on how much the downlink timing offset is,
wherein the channel is selected in consideration of whether the channel interferes with a control channel of the serving cell;
generating, by the serving cell, interference cancellation assistance information for the selected channel; and
transmitting, by the serving cell, the interference cancellation assistance information to the user equipment,
wherein the interference cancellation assistance information includes information on a number of transmission antennas of the neighbor interfering cell that causes interference and an Evolved Universal Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN).
2. The method of claim 1 , wherein the control channel includes at least one of a Physical Downlink Control Channel (PDCCH), a Physical Control Format Indicator Channel (PCFICH) and a Physical Hybrid Automatic Repeat Request (HARQ) Indicator Channel (PHICH).
3. The method of claim 1 , wherein the determining the downlink timing offset includes:
exchanging, by the serving cell, information on the downlink timing offset with the neighbor interfering cell.
4. The method of claim 1 , wherein the generating the interference cancellation assistance information includes:
acquiring, by the serving cell, information on the selected channel from the neighbor interfering cell; and
generating, by the serving cell, the interference cancellation assistance information based on the acquired information.
5. The method of claim 1 , wherein if the downlink timing offset is zero or a unit of a subframe, the channel which is subjected to the interference cancellation is a control channel of the neighbor interfering cell that exerts interference to the control channel of the serving cell.
6. The method of claim 1 , wherein if the downlink timing offset corresponds to five to six symbols and the control channel of the serving cell is transmitted on two symbols, the channel which is subjected to the interference cancellation is at least one of a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), an extended Physical Downlink Control Channel (e-PDCCH) and a Physical Downlink Shared Channel (PDSCH) of the neighbor interfering cell that exerts interference to the control channel of the serving cell.
7. The method of claim 1 , wherein if the downlink timing offset corresponds to seven to ten symbols and the control channel of the serving cell is transmitted on two symbols, the channel which is subjected to the interference cancellation is at least one of a PBCH, an e-PDCCH and a PDSCH of the neighbor interfering cell that exerts interference to the control channel of the serving cell.
8. The method of claim 1 , wherein the interference cancellation assistance information further includes at least one of system bandwidth information, scrambling code seed, transmission mode, System Frame Number (SFN) offset and the downlink timing offset.
9. The method of claim 1 , wherein the interference cancellation assistance information further includes information on common search space for a neighbor user equipment that belongs to the neighbor interfering cell.
10. A serving base station for transmitting assistance information for interference cancellation for a user equipment, the serving base station comprising:
a processor configured to:
determine a downlink timing offset with a neighbor interfering cell,
select a channel which is subjected to an interference cancellation among channels of the neighbor interfering cell based on how much the downlink timing offset is,
wherein the channel is selected in consideration of whether the channel interferes with a control channel of the serving base station, and
generate interference cancellation assistance information for the selected channel; and
a radio frequency (RF) unit configured to transmit the interference cancellation assistance information for the selected channel to the user equipment,
wherein the interference cancellation assistance information includes information on a number of transmission antennas of the neighbor interfering cell that causes interference and an Evolved Universal Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN).
11. The serving base station of claim 10 , wherein the control channel includes at least one of a Physical Downlink Control Channel (PDCCH), a Physical Control Format Indicator Channel (PCFICH) and a Physical Hybrid Automatic Repeat Request (HARQ) Indicator Channel (PHICH).
12. The serving base station of claim 10 , wherein the processor determines the downlink timing offset by exchanging information on the downlink timing offset with the neighbor interfering cell.
13. The serving base station of claim 10 , wherein the processor acquires information on the selected channel from the neighbor interfering cell and generates the interference cancellation assistance information based on the acquired information.