Method and apparatus for receiving downlink reference signal in wireless communication system
The present disclosure relates to a pre-5 th -Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4 th -Generation (4G) communication system such as Long Term Evolution (LTE). A method for operating a terminal in a wireless communication system, the method comprises determining a time-frequency structure of a downlink reference signal, and receiving, from a base station, the downlink reference signal according to the time-frequency structure.
1. A method for operating a terminal in a wireless communication system, the method comprising:
receiving, from a base station, synchronization signals;
identifying a first time-frequency structure of a first demodulation reference signal for a master information block (MIB) based on information carried on the synchronization signals;
receiving, from the base station, the first demodulation reference signal for the MIB based on the first time-frequency structure;
receiving, from the base station, configuration information for a second time-frequency structure of a second demodulation reference signal for physical downlink shared channel (PDSCH) by a higher layer signaling; and
receiving, from the base station, the second demodulation reference signal for PDSCH based on the configuration information.
2. The method of claim 1 , further comprising:
obtaining a subcarrier spacing of a synchronization signal based on the synchronization signal; and
determining a subcarrier spacing for the first time-frequency structure of the first demodulation reference signal as the obtained subcarrier spacing of the synchronization signal.
3. The method of claim 1 , further comprising:
performing first channel estimation based on the received first demodulation reference signal;
obtaining the MIB based on a result of the first channel estimation;
performing second channel estimation based on the received second demodulation reference signal; and
obtaining data on the PDSCH based on a result of the second channel estimation.
4. The method of claim 1 ,
wherein, when a subcarrier spacing for each resource element (RE) of the second time-frequency structure of the second demodulation reference signal is changed, a frequency-domain density and a time-domain density are maintained and a length of cyclic prefix (CP) is changed,
wherein the frequency-domain density comprises frequency intervals between adjacent REs of downlink reference signals in a frequency-domain, and
wherein the time-domain density comprises time intervals between adjacent REs of downlink reference signals in a time-domain.
5. A method for operating a base station in a wireless communication system, the method comprising:
transmitting, to a terminal, synchronization signals;
transmitting, to the terminal, a first demodulation reference signal for a master information block (MIB) based on a first time-frequency structure, wherein the first time-frequency structure are identified based on information carried on the synchronization signals;
transmitting, to the terminal, configuration information for a second time-frequency structure of a second demodulation reference signal for physical downlink shared channel (PDSCH) by a higher layer signaling; and
transmitting, to the terminal, the second demodulation reference signal for PDSCH based on the configuration information.
6. The method of claim 5 , further comprising:
configuring the first time-frequency structure of the first demodulation reference signal based on a subcarrier spacing of a synchronization signal.
7. The method of claim 5 , further comprising:
transmitting the MIB with the first demodulation reference signal on a first channel; and
transmitting data on the PDSCH with the second demodulation reference signal on a second channel.
8. The method of claim 5 ,
wherein, when a subcarrier spacing for each resource element (RE) of the second time-frequency structure of the second demodulation reference signal is changed, a frequency-domain density and a time-domain density are maintained and a length of a cyclic prefix (CP) is changed,
wherein the frequency-domain density comprises frequency intervals between adjacent REs of downlink reference signals in a frequency-domain, and
wherein the time-domain density comprises time intervals between adjacent REs of downlink reference signals in a time-domain.
9. A terminal in a wireless communication system, the terminal comprising:
at least one transceiver; and
at least one processor operably coupled to the at least one transceiver, and configured to:
receive, from a base station, synchronization signals;
identify a first time-frequency structure of a first demodulation reference signal for a master information block (MIB) based on information carried on the synchronization signals;
receive, from the base station, the first demodulation reference signal for the MIB based on the first time-frequency structure;
receive, from the base station, configuration information for a second time-frequency structure of a second demodulation reference signal for physical downlink shared channel (PDSCH) by a higher layer signaling; and
receive, from the base station, the second demodulation reference signal for PDSCH based on the configuration information.
10. The terminal of claim 9 , wherein the at least one processor is further configured to:
obtain a subcarrier spacing of a synchronization signal based on the synchronization signal; and
determine a subcarrier spacing for the first time-frequency structure of the first demodulation reference signal as the obtained subcarrier spacing of the synchronization signal.
11. The terminal of claim 9 , wherein the at least one processor is further configured to:
perform a first channel estimation based on the received first demodulation reference signal;
obtain the MIB based on a result of the first channel estimation;
perform a second channel estimation based on the received second demodulation reference signal; and
obtain data on the PDSCH based on a result of the second channel estimation.
12. The terminal of claim 9 ,
wherein, when a subcarrier spacing for each resource element (RE) of the second time-frequency structure of the second demodulation reference signal is changed, a frequency-domain density and a time-domain density are maintained and a length of a cyclic prefix (CP) is changed,
wherein the frequency-domain density comprises frequency intervals between adjacent REs of downlink reference signals in a frequency-domain, and
wherein the time-domain density comprises time intervals between adjacent REs of downlink reference signals in a time-domain.
13. A base station in a wireless communication system, the base station comprising:
at least one transceiver; and
at least one processor operably coupled to the at least one transceiver, and configured to:
transmit, to a terminal, synchronization signals;
transmit, to the terminal, a first demodulation reference signal for a master information block (MIB) based on a first time-frequency structure, wherein the first time-frequency structure are identified based on information carried on the synchronization signals;
transmit, to the terminal, configuration information for a second time-frequency structure of a second demodulation reference signal for physical downlink shared channel (PDSCH) by a higher layer signaling; and
transmit, to the terminal, the second demodulation reference signal for PDSCH based on the configuration information.
14. The base station of claim 13 , wherein the at least one processor is further configured to configure the first time-frequency structure of the first demodulation reference signal based on a subcarrier spacing of a synchronization signal.
15. The base station of claim 13 , wherein the at least one processor is further configured to:
transmit the MIB with the first demodulation reference signal on a first channel; and
transmit data on the PDSCH with the second demodulation reference signal on a second channel.
16. The base station of claim 13 ,
wherein, when a subcarrier spacing for each resource element (RE) of the second time-frequency structure of the second demodulation reference signal is changed, a frequency-domain density and a time-domain density are maintained and a length of cyclic prefix (CP) is changed,
wherein the frequency-domain density comprises frequency intervals between adjacent REs of downlink reference signals in a frequency-domain, and
wherein the time-domain density comprises time intervals between adjacent REs of downlink reference signals in a time-domain.