Method of notifying resource allocation for demodulation reference signals
A method of notifying resource allocation for Demodulation Reference Signal (DMRS) is provided. A base station notifies to a user equipment a power offset value between an average EPRE value for data symbols and an average EPRE value for the DMRS at each layer in a semi-static or static manner. Also, the base station dynamically notifies to the user equipment a current channel rank or a current DMRS distribution pattern for the user equipment. The user equipment determines an allocated DMRS antenna port based on a correspondence between the received channel rank and an allocation of DMRS antenna port, thereby obtaining resource allocation information for the DMRS. The signaling overhead for power allocation in the system can be reduced, the efficiency of power amplifier can be improved and the flexibility of system scheduling can be increased. A method of notifying antenna port resource allocation for DMRS is also provided.
1. A wireless communication method in which a base station apparatus communicates with a user equipment, the wireless communication method comprising:
transmitting, to the user equipment, bit information, wherein
the bit information indicates first information indicating one or more antenna ports and second information indicating a number of layers for downlink data symbols; and
transmitting, to the user equipment, the downlink data symbols and Demodulation Reference Signal (DMRS) on the basis of a power offset between an Energy Per Resource Element (EPRE) for the downlink data symbols and an EPRE for the DMRS,
wherein the power offset is set to 0 dB or 3 dB on the basis of the second information.
2. The method according to claim 1 , wherein:
the number of layers corresponds to more than one layer.
3. The method according to claim 1 , wherein:
the bit information is dynamically transmitted to the user equipment.
4. A wireless communication method in which a user equipment communicates with a base station apparatus, the wireless communication method comprising:
receiving, from the base station apparatus, bit information, wherein
the bit information indicates first information indicating one or more antenna ports and second information indicating a number of layers for downlink data symbols;
receiving the downlink data symbols and Demodulation Reference Signal (DMRS) on the basis of a power offset between an Energy Per Resource Element (EPRE) for the downlink data symbols and an EPRE for the DMRS, wherein the power offset is set to 0 dB or 3 dB on the basis of the second information.
5. The method according to claim 4 , wherein:
the number of layers corresponds to more than one layer.
6. A base station apparatus which configured to communicate with a user equipment, the base station apparatus comprising:
a transmitting unit configured to transmit, to the user equipment, bit information, wherein
the bit information indicates first information indicating one or more antenna ports and second information indicating a number of layers for downlink data symbols; and
a setting unit configured to set a power offset to 0 dB or 3 dB on the basis of the second information, the power offset being a power offset between an Energy Per Resource Element (EPRE) for the downlink data symbols and an EPRE for Demodulation Reference Signal (DMRS),
the transmission unit configured to transmit the DMRS and the downlink data symbols on transmit power based on the power offset.
7. The base station apparatus according to claim 6 , wherein:
the number of layers corresponds to more than one layer.
8. The base station apparatus according to claim 6 , wherein:
the bit information is dynamically transmitted to the user equipment.
9. A user equipment which configured to communicate with a base station apparatus, the user equipment comprising:
a receiving unit configured to receive, from the base station apparatus, bit information, wherein
the bit information indicates first information indicating one or more antenna ports and second information indicating a number of layers for downlink data symbols; and
a setting unit configured to set a power offset to 0 dB or 3 dB on the basis of the second information, the power offset being a power offset between an Energy Per Resource Element (EPRE) for the downlink data symbols and an EPRE for Demodulation Reference Signal (DMRS),
wherein the reception unit is configured to receive the downlink data symbols and the DMRS on the basis of the power offset.
10. The user equipment according to claim 9 , wherein:
the number of layers corresponds to more than one layer.
11. The user equipment according to claim 9 , wherein:
the bit information is dynamically received from the base station apparatus.
12. The method according to claim 4 , wherein:
the bit information is dynamically received from the base station apparatus.
13. The method according to claim 1 , the method comprising:
setting an index to the bit information, the index is an index of a table which is comprised by the first information and the second information.
14. The method according to claim 13 , the method comprising:
configuring the index based on both a value of the first information and a value of the second information.
15. The method according to claim 4 , the method comprising:
detecting a index via the bit information, the index is a index of a table which is comprised by the first information and the second information.
16. The method according to claim 15 , the method comprising:
setting a value of the first information and a value of the second information on the basis of the index.
17. The base station apparatus according to claim 6 , the base station apparatus comprising:
a configuring unit configured to set an index to the bit information, the index is an index of a table which is comprised by the first information and the second information.
18. The base station apparatus according to claim 17 , wherein:
the configuring unit is configured to configure the index based on both a value of the first information and a value of the second information.
19. The user equipment according to claim 9 , the user equipment comprising:
a detecting unit configured to detect a index via the bit information, the index is a index of a table which is comprised by the first information and the second information.
20. The user equipment according to claim 19 , wherein:
the setting unit is configured to set a value of the first information and a value of the second information on the basis of the index.