Method for measuring state of channel quality in wireless communication system including cells formed with a plurality of network nodes, and apparatus therefor
Disclosed are a method for measuring a state of channel quality in a wireless communication system including cells formed with a plurality of network nodes and an apparatus therefor. The method of enabling a terminal to measure the state of channel quality in the wireless communication system including the cells formed with the plurality of network nodes, includes the steps of: receiving the information related to a resource in which at least one first type network node transmits a Channel State Information-Reference Signal (CSI-RS); and measuring the intensity of a received signal on only the resource for transmitting the CSI-RS according to at least one first type network node on the basis of the received information.
1. A method of measuring a channel state by a user equipment in a network including a plurality of network nodes, the method comprising:
receiving, from a network, channel state information-reference signal (CSI-RS) transmission pattern information,
wherein the CSI-RS transmission pattern information indicates two orthogonal frequency division multiplexing (OFDM) symbols in a first slot of a subframe and at least two OFDM symbols in a second slot of the subframe are configured for CSI-RS transmission;
receiving, from the network, information indicating the two OFDM symbols in the first slot of the subframe on which a muting operation will be performed for the user equipment;
receiving channel state information-reference signals (CSI-RSs) of a first type network node in corresponding resource elements (REs) of the two OFDM symbols in the first slot of the subframe,
wherein CSI-RSs of a second type network node are configured as zero-power CSI-RSs in the corresponding REs of the two OFDM symbols in the first slot of the subframe, and
wherein the CSI-RSs of the second type network node are configured as non-zero power CSI-RSs on at least two OFDM symbols in the second slot of the subframe;
receiving the CSI-RSs of the second type network node in at least two OFDM symbols in the second slot of the subframe;
measuring a channel state of the first type network node for the corresponding REs of the two OFDM symbols in the first slot of the subframe; and
transmitting information related to the measured channel state to the second type network node.
2. The method of claim 1 , wherein the first type network node comprises a pico base station or a femto base station.
3. The method of claim 1 , wherein the second type network node comprises a macro base station.
4. The method of claim 1 , wherein the measured channel state is represented as a Reference Signal Received Power (RSRP) or a Received Signal Strength Indicator (RSSI).
5. The method of claim 1 , wherein the first type network node and the second type network node have a same cell Identifier (ID).
6. A user equipment for measuring a channel state in a network including a plurality of network nodes, the user equipment comprising:
a receiver configured to
receive, from a network, channel state information-reference signal (CSI-RS) transmission pattern information;
wherein the CSI-RS transmission pattern information indicates two orthogonal frequency division multiplexing (OFDM) symbols in a first slot of a subframe and at least two OFDM symbols in a second slot of the subframe are configured for CSI-RS transmission;
receive, from the network, information indicating the two OFMD symbols in the first slot of the subframe on which a muting operation will be performed for the user equipment;
receive channel state information-reference signals (CSI-RSs) of a first type network node in corresponding resource elements (REs) of the two OFDM symbols in the first slot of a subframe,
wherein CSI-RSs of a second type network node are configured as zero-power CSI-RSs in the corresponding REs of the two OFDM symbols in the first slot of the subframe, and
wherein the CSI-RSs of the second type network node are configured as non-zero power CSI-RSs on at least two OFDM symbols in the second slot of the subframe; and
receive the CSI-RSs of the second type network node in at least two OFDM symbols in the second slot of the subframe;
a processor configured to measure a channel state of the first type network node for the corresponding REs of the two OFDM symbols in the first slot of the subframe; and
a transmitter configured to transmit information related to the measured channel state to the second type network node.
7. The user equipment of claim 6 , wherein the measured channel state is represented as a Reference Signal Received Power (RSRP) or a Received Signal Strength Indicator (RSSI).
8. The method of claim 1 , wherein OFDM symbol indexes of the two OFMD symbols in the first slot of the subframe comprise OFDM symbol indexes 5 and 6 .
9. The method of claim 1 , wherein OFDM symbol indexes of the at least two OFMD symbols in the second slot of the subframe comprise at least OFDM symbol indexes 12 and 13 .
10. The user equipment of claim 6 , wherein OFDM symbol indexes of the two OFMD symbols in the first slot of the subframe comprise OFDM symbol indexes 5 and 6 .
11. The user equipment of claim 6 , wherein OFDM symbol indexes of the at least two OFMD symbols in the second slot of the subframe comprise at least OFDM symbol indexes 12 and 13 .