Retransmission methods including discontinuous transmission and related devices
A method of operating a node of a radio access network may include transmitting first and second data blocks from the radio access network over respective first and second MIMO layers of a MIMO wireless channel to a wireless terminal during a first TTI. Responsive to receiving a NACK message for the second data block, downlink signaling for a second TTI may be transmitted from the radio access network to the wireless terminal with the downlink signaling including a DTX indicator for the first MIMO layer and a retransmission data indicator for the second MIMO layer. Responsive to receiving the NACK message for the second data block, the second data block may be retransmitted from the radio access network over the second MIMO layer to the wireless terminal during a second TTI.
1. A method of operating a node of a radio access network, the method comprising:
selecting first and second HARQ process identifications for first and second multiple-input-multiple-output (MIMO) layers of a MIMO wireless channel;
transmitting first and second data blocks from the radio access network respectively over the first and second MIMO layers of the MIMO wireless channel to a wireless terminal during a first transmission time interval (TTI);
responsive to receiving a negative acknowledgment (NACK) message for the second data block, generating a HARQ discontinuous transmission (HARQ-DTX) process identification for the first MIMO layer as a function of the second HARQ process identification for the second MIMO layer;
responsive to receiving the NACK message for the second data block, transmitting downlink signaling for a second TTI from the radio access network to the wireless terminal wherein the downlink signaling includes a discontinuous transmission (DTX) indicator for the first MIMO layer and a retransmission data indicator for the second MIMO layer, wherein the downlink signaling for the second TTI including the DTX indicator and the retransmission data indicator is transmitted using a downlink signaling channel; and
responsive to receiving the NACK message for the second data block, retransmitting the second data block from the radio access network over the second MIMO layer to the wireless terminal during the second TTI, wherein the second data block is retransmitted over the second MIMO layer using a downlink traffic channel.
2. The method of claim 1 wherein transmitting the downlink signaling comprises transmitting the downlink signaling responsive to receiving an acknowledgment (ACK) message for the first data block and responsive to receiving the NACK message for the second data block, and wherein retransmitting the second data block comprises retransmitting the second data block responsive to receiving the ACK message for the first data block and responsive to receiving the NACK message for the second data block.
3. The method of claim 1 wherein retransmitting the second data block during the second TTI comprises retransmitting the second data block without transmitting data over the first MIMO layer during the second TTI.
4. The method of claim 1 :
wherein transmitting the first and second data blocks during the first transmission time interval (TTI) comprises transmitting the first and the second data blocks after selecting the first and second HARQ process identifications for the first and second MIMO layers; and
wherein transmitting the downlink signaling for the second, TTI comprises transmitting the downlink signaling for the second TTI after generating the HARQ-DTX process identification for the first MIMO layer.
5. The method according to claim 1 further comprising:
responsive to selecting the first and second HARQ process identifications, transmitting downlink signaling from the radio access network to the wireless terminal for the first transmission time interval (TTI);
wherein transmitting the downlink signaling for the second TTI comprises transmitting the downlink signaling for the second TTI responsive to generating the HARQ-DTX process identification and responsive to receiving the NACK message for the second data block, and
wherein retransmitting the second data block comprises retransmitting the second data block responsive to generating the HARQ-DTX process identification and responsive to receiving the NACK message for the second data block.
6. The method of claim 1 wherein the downlink signaling channel is a High Speed Shared Control Channel (HS-SCCH), and wherein the downlink traffic channel is a High Speed Physical Downlink Shared Channel (HS-PDSCH).
7. A method of operating a node of a radio access network, the method comprising:
transmitting first and second data blocks from the radio access network over respective first and second multiple-input-multiple-output (MIMO) layers of a MIMO wireless channel to a wireless terminal during a first transmission time interval (TTI);
responsive to receiving a negative acknowledgment (NACK) message for the first data block and a NACK message for the second data block, transmitting downlink signaling for a second TTI from the radio access network to the wireless terminal wherein the downlink signaling includes a discontinuous transmission (DTX) indicator for the first MIMO layer and a retransmission data indicator for the second MIMO layer; and
responsive to receiving the NACK message for the first data block and the NACK message for the second data block, retransmitting the second data block from the radio access network over the second MIMO layer to the wireless terminal during the second TTI.
8. The method of claim 7 wherein retransmitting the second data block during the second TTI comprises retransmitting the second data block without transmitting data over the first MIMO layer during the second TTI.
9. The method of claim 7 further comprising:
responsive to receiving an acknowledgment (ACK) message for the retransmission of the second data block during the second TTI, transmitting downlink signaling from the radio access network to the wireless terminal for a third TTI wherein the downlink signaling for the third TTI includes a discontinuous transmission (DTX) indicator for the second MIMO layer and a retransmission data indicator for the first MIMO layer; and
responsive to receiving the ACK message for the retransmission of the second data block during the second TTI, retransmitting the first data block from the radio access network over the first MIMO layer to the wireless terminal during the third TTI.
10. The method of claim 7 further comprising:
before transmitting the first and second data blocks during the first transmission time interval, selecting first and second HARQ process identifications for the first and second MIMO layers; and
before transmitting the downlink signaling for the second TTI, generating a HARQ-DTX process identification for the first MIMO layer as a function of the second HARQ process identification for the second MIMO layer.
11. A method of operating a node of a radio access network, the method comprising:
transmitting first and second data blocks from the radio access network over respective first and second multiple-input-multiple-output (MIMO) layers of a MIMO wireless channel to a wireless terminal during a first transmission time interval (TTI) in accordance with a first MIMO rank;
responsive to receiving a negative acknowledgment (NACK) message for the second data block and responsive to receiving a preference for a second MIMO rank less than the first MIMO rank from the wireless terminal, transmitting downlink signaling for a second TTI from the radio access network to the wireless terminal wherein the downlink signaling includes a discontinuous transmission (DTX) indicator for the first MIMO layer and a retransmission data indicator for the second MIMO layer; and
responsive to receiving the NACK message for the second data block and responsive to receiving the preference for the second MIMO rank less than the first MIMO rank, retransmitting the second data block from the radio access network over the second MIMO layer to the wireless terminal during the second TTI in accordance with the first MIMO rank.
12. The method of claim 11 wherein transmitting the downlink signaling comprises transmitting the downlink signaling responsive to receiving a NACK for the first data block, responsive to receiving the NACK message for the second data block, and responsive to receiving the preference for the second MIMO rank less than the first rank.
13. The method of claim 12 wherein retransmitting the second data block during the second TTI comprises retransmitting the second data block without transmitting data over the first MIMO layer during the second TTI.
14. The method of claim 11 further comprising:
responsive to receiving an acknowledgment (ACK) message for the retransmission of the second data block during the second TTI, transmitting downlink signaling from the radio access network to the wireless terminal for a third TTI wherein the downlink signaling for the third TTI includes a retransmission data indicator for the first MIMO layer and a discontinuous transmission (DTX) indicator for the second MIMO layer; and
responsive to receiving the acknowledgment (ACK) message for the retransmission of the second data block during the second TTI, retransmitting the first data block from the radio access network over the second MIMO layer to the wireless terminal during the third TTI in accordance with the first MIMO rank.
15. The method according to claim 11 further comprising:
before transmitting the first and second data blocks during the first transmission time interval, selecting first and second HARQ process identifications for the first and second MIMO layers; and
before transmitting the downlink signaling for the second TTI, generating a HARQ-DTX process identification for the first MIMO layer as a function of the second HARQ process identification for the second MIMO layer.
16. A node of a radio access network, the node comprising:
a transceiver configured to communicate with a wireless terminal over a multiple-input-multiple-output (MIMO) wireless channel; and
a processor coupled to the transceiver, wherein the processor is configured to,
select first and second HARQ process identifications for first and second MIMO layers of the MIMO wireless channel;
transmit first and second data blocks through the transceiver respectively over the first and second MIMO layers of the MIMO wireless channel to a wireless terminal during a first transmission time interval (TTI),
generate a HARQ discontinuous transmission (HARQ-DTX) process identification for the first MIMO layer as a function of the second HARQ process identification for the second MIMO layer responsive to receiving a negative acknowledgment (NACK) message for the second data block;
transmit downlink signaling for a second TTI through the transceiver to the wireless terminal responsive to receiving the NACK message for the second data block, wherein the downlink signaling includes a discontinuous transmission (DTX) indicator for the first MIMO layer and a retransmission data indicator for the second MIMO layer, wherein the downlink signaling for the second TTI including the DTX indicator and the retransmission data indicator is transmitted using a downlink signaling channel, and
retransmit the second data block through the transceiver over the second MIMO layer to the wireless terminal during the second TTI responsive to receiving the NACK message for the second data block, wherein the second data block is retransmitted over the second MIMO layer using a downlink traffic channel.
17. The node of claim 16 wherein the processor is configured to transmit the downlink signaling responsive to receiving an acknowledgment (ACK) message for the first data block and responsive to receiving the NACK message for the second data block, and wherein the processor is configured to retransmit the second data block responsive to receiving the ACK message for the first data block and responsive to receiving the NACK message for the second data block.
18. The node of claim 16 wherein the processor is further configured to,
transmit downlink signaling from the radio access network to the wireless terminal for the first TTI responsive to selecting the first and second HARQ process identifications,
wherein transmitting the downlink signaling for the second TTI comprises transmitting the downlink signaling for the second TTI responsive to generating the HARQ-DTX process identification and responsive to receiving the NACK message for the second data block, and
wherein retransmitting the second data block comprises retransmitting the second data block responsive to generating the HARQ-DTX process identification and responsive to receiving the NACK message for the second data block.
19. The node of claim 16 wherein the processor is configured to retransmit the second data block without transmitting data over the first MIMO layer during the second TTI.
20. The node of claim 16 wherein the downlink signaling channel is a High Speed Shared Control Channel (HS-SCCH), and wherein the downlink traffic channel is a High Speed Physical Downlink Shared Channel (HS-PDSCH).
21. A node of a radio access network, the node comprising:
a transceiver configured to communicate with a wireless terminal over a multiple-input-multiple-output (MIMO) wireless channel; and
a processor coupled to the transceiver, wherein the processor is configured to,
transmit first and second data blocks through the transceiver over respective first and second MIMO layers of the MIMO wireless channel to a wireless terminal during a first transmission time interval (TTI),
transmit downlink signaling for a second TTI through the transceiver to the wireless terminal responsive to receiving a negative acknowledgment (NACK) message for the first data block and a NACK message for the second data block, wherein the downlink signaling includes a discontinuous transmission (DTX) indicator for the first MIMO layer and a retransmission data indicator for the second MIMO layer, and
retransmit the second data block through the transceiver over the second MIMO layer to the wireless terminal during the second TTI responsive to receiving the NACK message for the first data block and the NACK messages for the second data block.
22. The node of claim 21 wherein the processor is configured to retransmit the second data block during the second TTI by retransmitting the second data block without transmitting data over the first MIMO layer during the second TTI.
23. A node of a radio access network, the node comprising:
a transceiver configured to communicate with a wireless terminal over a multiple-input-multiple-output (MIMO) wireless channel; and
a processor coupled to the transceiver, wherein the processor is configured to,
transmit first and second data blocks through the transceiver over respective first and second MIMO layers of the MIMO wireless channel to a wireless terminal in accordance with a first MIMO rank during a first transmission time interval (TTI),
transmit downlink signaling for a second TTI through the transceiver to the wireless terminal responsive to receiving a negative acknowledgement (NACK) message for the second data block and responsive to receiving a preference for a second MIMO rank less than the first rank from the wireless terminal, wherein the downlink signaling includes a discontinuous transmission (DTX) indicator for the first MIMO layer and a retransmission data indicator for the second MIMO layer, and
retransmit the second data block through the transceiver over the second MIMO layer to the wireless terminal during the second TTI in accordance with the first MIMO rank responsive to receiving the NACK message for the second data block and responsive to receiving the NACK message for the second data block and responsive to receiving the preference for the second MIMO rank less than the first MIMO rank.
24. The node of claim 23 wherein the processor is further configured to transmit the downlink signaling responsive to receiving a NACK for the first data block, responsive to receiving the NACK message for the second data block, and responsive to receiving the preference for the second MIMO rank less than the first rank.