Method and user equipment for receiving downlink signal, and method and base station for transmitting downlink signal
Disclosed herein is a method and apparatus for transmitting/receiving a signal in a wireless communication system supporting NB-IoT. An eNB provides a user equipment (UE), for which NB-IoT is not configured, with information about frequency bands (anchor RBs) possibly having a synchronization signal for NB-IoT (hereinafter, an NB-IoT SS). When the eNB transmits a downlink signal to the UE, it may puncture the downlink signal on an RB having the NB-IoT SS, based on the information. When the UE transmits an uplink signal, it may puncture the uplink signal on an RB having the NB-IoT SS, based on the information.
1. A method of transmitting a downlink signal by a base station in a wireless communication system, the method comprising:
in response to a transmission of a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) for a narrowband Internet of Things (NB-loT) UE overlapping with a transmission of a first downlink channel for a Machine-Type Communications UE (MTC UE) in a first subframe:
transmitting the PSS or the SSS for the NB-loT UE; and
dropping the transmission of the first downlink channel for the MTC UE in the first subframe, and
in response to a transmission of a physical random access channel (PRACH) for the MTC UE overlapping with a transmission of a second downlink channel for the NB-loT UE in a second subframe:
transmitting the PRACH for the MTC UE in the second subframe; and
dropping the transmission of the second downlink channel for the NB-loT UE in the second subframe.
2. The method according to claim 1 , wherein the PRACH for the MTC UE is transmitted on six physical resource blocks (PRBs).
3. The method according to claim 1 , wherein the PSS or the SSS for the NB-IoT UE is transmitted on a physical resource block (PRB).
4. A base station for transmitting a downlink signal in a wireless communication system, the base station comprising: a radio frequency (RF) unit; and a processor configured to control the RF unit, wherein the processor is configured to control the RF unit to:
in response to a transmission of a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) for a narrowband Internet of Things (NB-loT) UE overlapping with a transmission of a first downlink channel for a Machine-Type Communications UE (MTC UE) in a first subframe:
transmit the PSS or the SSS for the NB-loT UE in the first subframe; and
drop the transmission of the first downlink channel for the MTC UE in the subframe, and
in response to a transmission of a physical random access channel (PRACH) for the MTC UE overlapping with a transmission of a second downlink channel for the NB-loT UE in a second subframe:
transmit the PRACH for the MTC UE in the second subframe; and
drop the transmission of the second downlink channel for the NB-loT UE in the second subframe.
5. The base station according to claim 4 , wherein the PRACH for the MTC UE is transmitted on six physical resource blocks (PRBs).
6. The base station according to claim 4 , wherein the PSS or the SSS for the NB-IoT UE is transmitted on a physical resource block (PRB).