Redundancy version selection based on receiving quality and transport format
The embodiments herein relate to a method in a base station ( 101 ) for transmitting a transport block to a user equipment ( 105 ) in a communications network ( 100 ). The transport block comprises a plurality of bits. The base station ( 101 ) selects ( 203 a, 203 b, 401 ) a transport format. The base station ( 101 ) dynamically selects ( 204 a, 203 b, 402 ) a first redundancy version parameter based on a decoding performance for the transport block. The base station ( 101 ) transmits ( 205 a, 204 b, 404 ) the transport block comprising the plurality of bits distributed according to the dynamically selected first redundancy version parameter and according to the selected transport format in a first transmission to the user equipment ( 105 ).
1. A method, in a base station, for transmitting a transport block to a user equipment in a communications network, the transport block comprising a plurality of bits, the method comprising:
receiving information about a reception quality from the user equipment;
selecting a transport format based on the reception quality;
dynamically selecting, for a first transmission, a first redundancy version parameter based on the selected transport format for the transport block;
transmitting, in a first transmission, to the user equipment the transport block with the plurality of bits distributed according to the selected first redundancy version parameter and according to the selected transport format,
wherein the transport format and the first redundancy version parameter are selected jointly from a table comprising information about required signal reception quality at the user equipment for each combination of transport format and first redundancy version parameter of a plurality of transport format and first redundancy version parameter combinations.
2. The method of claim 1 , further comprising:
selecting a second redundancy version parameter based on the first redundancy version parameter; and
retransmitting, to the user equipment, the transport block with the plurality of bits distributed according to the selected second redundancy version parameter and according to the selected transport format.
3. The method of claim 1 , further comprising updating, based on the selected first redundancy version parameter, the information about required signal reception quality in the table.
4. The method of claim 1 , wherein the table comprises information about an optimal first redundancy version parameter for each transport format of a plurality of transport formats.
5. The method of claim 1 , wherein the dynamically selecting comprises dynamically selecting based on the selected transport format for the transport block and a decoding performance for the transport block, the decoding performance is associated with at least one of:
a block error rate;
a reliability distribution of the plurality of bits in at least one code block;
a distribution of systematic bits and parity bits in the at least one code block.
6. A base station for transmitting a transport block to a user equipment in a communications network, the transport block comprising a plurality of bits, the base station configured to receive information about a reception quality from the user equipment; the base station comprising:
one or more processing circuits configured to function as a selector configured to:
select a transport format based on the reception quality; and
dynamically select, for a first transmission, a first redundancy version parameter based on the selected transport format for the transport block;
a transmitter configured to transmit, in a first transmission to the user equipment, the transport block with the plurality of bits distributed according to the selected first redundancy version parameter and according to the selected transport format,
wherein the one or more processing circuits are configured to select the transport format and the first redundancy version parameter jointly from a table comprising information about required signal reception quality at the user equipment for each combination of transport format and first redundancy version parameter of a plurality of transport format and first redundancy version parameter combinations.
7. The base station of claim 6 :
wherein the one or more processing circuits are further configured to select a second redundancy version parameter based on the first redundancy version parameter;
wherein the transmitter is further configured to retransmit, to the user equipment, the transport block with the plurality of bits distributed according to the dynamically selected second redundancy version parameter and according to the selected transport format.
8. The base station of claim 6 , wherein the one or more processing circuits are configured to further function as an updating unit configured to, based on the selected first redundancy version parameter, update the information about required signal reception quality in the table.
9. The base station of claim 6 , wherein the table comprises information about an optimal first redundancy version parameter for each transport format of a plurality of transport formats.
10. The base station of claim 6 , wherein the one or more processing circuits are configured to dynamically select based on the selected transport format for the transport block and a decoding performance for the transport block, the decoding performance is associated with at least one of:
a block error rate;
a reliability distribution of the plurality of bits in at least one code block;
a distribution of systematic bits and parity bits in the at least one code block.
11. A method, in a base station, for transmitting a transport block to a user equipment in a communications network, the transport block comprising a plurality of bits, the method comprising:
receiving information about a reception quality from the user equipment;
selecting a transport format based on the reception quality;
dynamically selecting, for a first transmission, a first redundancy version parameter based on the selected transport format for the transport block;
transmitting, in a first transmission, to the user equipment the transport block with the plurality of bits distributed according to the selected first redundancy version parameter and according to the selected transport format,
wherein the transport format is selected from a table comprising information about required signal reception quality at the user equipment for each transport format of a plurality of transport formats and for each first redundancy version parameter of a plurality of first redundancy version parameters.
12. The method of claim 11 , further comprising:
selecting a second redundancy version parameter based on the first redundancy version parameter; and
retransmitting, to the user equipment, the transport block with the plurality of bits distributed according to the selected second redundancy version parameter and according to the selected transport format.
13. The method of claim 11 , further comprising updating, based on the selected first redundancy version parameter, the information about required signal reception quality in the table.
14. The method of claim 11 , wherein the table comprises information about an optimal first redundancy version parameter for each transport format of a plurality of transport formats.
15. The method of claim 11 , wherein the dynamically selecting comprises dynamically selecting based on the selected transport format for the transport block and a decoding performance for the transport block, the decoding performance is associated with at least one of:
a block error rate;
a reliability distribution of the plurality of bits in at least one code block;
a distribution of systematic bits and parity bits in the at least one code block.
16. A base station for transmitting a transport block to a user equipment in a communications network, the transport block comprising a plurality of bits, the base station configured to receive information about a reception quality from the user equipment; the base station comprising:
one or more processing circuits configured to function as a selector configured to:
select a transport format based on the reception quality; and
dynamically select, for a first transmission, a first redundancy version parameter based on the selected transport format for the transport block;
a transmitter configured to transmit, in a first transmission to the user equipment, the transport block with the plurality of bits distributed according to the selected first redundancy version parameter and according to the selected transport format,
wherein the one or more processing circuits are configured to select the transport format from a table comprising information about required signal reception quality at the user equipment for each transport format of a plurality of transport formats and for each first redundancy version parameter of a plurality of first redundancy version parameters.
17. The base station of claim 16 :
wherein the one or more processing circuits are further configured to select a second redundancy version parameter based on the first redundancy version parameter;
wherein the transmitter is further configured to retransmit, to the user equipment, the transport block with the plurality of bits distributed according to the dynamically selected second redundancy version parameter and according to the selected transport format.
18. The base station of claim 16 , wherein the one or more processing circuits are configured to further function as an updating unit configured to, based on the selected first redundancy version parameter, update the information about required signal reception quality in the table.
19. The base station of claim 16 , wherein the table comprises information about an optimal first redundancy version parameter for each transport format of a plurality of transport formats.
20. The base station of claim 16 , wherein the one or more processing circuits are configured to dynamically select based on the selected transport format for the transport block and a decoding performance for the transport block, the decoding performance is associated with at least one of:
a block error rate;
a reliability distribution of the plurality of bits in at least one code block;
a distribution of systematic bits and parity bits in the at least one code block.