Uplink control data transmission
Methods and systems for transmitting uplink control information and feedback are disclosed for carrier aggregation systems. A user equipment device may be configured to transmit uplink control information and other feedback for several downlink component carriers using one or more uplink component carriers. The user equipment device may be configured to transmit such data using a physical uplink control channel rather than a physical uplink shared channel. The user equipment device may be configured to determine the uplink control information and feedback data that is to be transmitted, the physical uplink control channel resources to be used to transmit the uplink control information and feedback data, and how the uplink control information and feedback data may be transmitted over the physical uplink control channel.
1. A method implemented by a wireless transmit/receive unit (WTRU) comprising:
encoding a set of control information bits to generate encoded control information bits;
scrambling the encoded control information bits to generate scrambled encoded control information bits;
modulating the scrambled control information bits into a plurality of modulated symbols;
spreading each of the plurality of modulated symbols block-wise using at least one orthogonal sequence, wherein the at least one orthogonal sequence is configured based on an index received via a radio resource control (RRC) message;
determining a cyclic shift based on the received index;
applying the cyclic shift to a base sequence to generate a demodulation reference signal (DMRS); and
sending a physical uplink control channel (PUCCH) transmission comprising the DMRS and the block-wise spread modulated symbols.
2. The method of claim 1 , wherein the cyclic shift is based on a slot number and a symbol number.
3. The method of claim 1 , wherein the set of control information bits comprises hybrid automatic repeat request (HARQ) acknowledgement (ACK)/negative-acknowledgement (NACK) bits.
4. The method of claim 1 , wherein the set of control information bits comprises one or more of hybrid automatic repeat request (HARQ) acknowledgement (ACK)/negative-acknowledgement (NACK) bits and a scheduling request (SR) bit.
5. The method of claim 4 , wherein the SR bit is appended to
the one or more HARQ ACK/NACK bits, and wherein the set of control information bits comprising the one or more HARQ ACK/NACK bits and the appended SR bit are jointly encoded.
6. The method of claim 1 , wherein a format associated with the PUCCH transmission is determined based on a number of control information bits to be included in the PUCCH transmission.
7. The method of claim 1 , wherein the modulation of the control information bits is performed after scrambling the control information bits.
8. The method of claim 1 , wherein the at least one orthogonal sequence is determined based on a length of the PUCCH transmission.
9. The method of claim 1 , wherein the encoded control information bits are scrambled using a scrambling sequence, wherein the scrambling sequence is based on a WTRU's cell radio network temporary identifier (C-RNTI) or an identity of a cell in which the PUCCH transmission is sent.
10. The method of claim 1 further comprising determining a number of control information bits to send, wherein the control information bits comprise hybrid automatic repeat request (HARQ) acknowledgement (ACK) bits, and the number of control information bits are determined based on a number of codewords received in the physical downlink shared channel (PDSCH) of one or more serving cells.
11. The method of claim 1 , wherein the PUCCH transmission is sent over PUCCH resources, wherein the PUCCH resources comprise one or more single carrier frequency-division multiple access (SC-FDMA) symbols.
12. The method of claim 1 , wherein the PUCCH transmission is a Discrete Fourier Transform (DFT) spread orthogonal frequency division multiplexing (OFDM) based PUCCH transmission.
13. A wireless transmit/receive unit (WTRU) comprising:
a processor configured to at least:
encode a set of control information bits to generate encoded control information bits;
scramble the encoded control information bits to generate scrambled encoded control information bits;
modulate the scrambled control information bits into a plurality of modulated symbols;
spread each of the plurality of modulated symbols block-wise using at least one orthogonal sequence, wherein the at least one orthogonal sequence is configured based on an index received via a radio resource control (RRC) message;
determine a cyclic shift based on the received index;
apply the cyclic shift to a base sequence to generate a demodulation reference signal (DMRS); and
send a physical uplink control channel (PUCCH) transmission comprising the DMRS and the block-wise spread modulated symbols.
14. The WTRU of claim 13 , wherein the cyclic shift is based on a slot number and a symbol number.
15. The WTRU of claim 13 , wherein the set of control information bits comprises hybrid automatic repeat request (HARQ) acknowledgement (ACK)/negative-acknowledgement (NACK) bits.
16. The WTRU of claim 13 , wherein the set of control information bits comprises one or more of hybrid automatic repeat request (HARQ) acknowledgement (ACK)/negative-acknowledgement (NACK) bits and a scheduling request (SR) bit.
17. The WTRU of claim 13 , wherein the SR bit is appended to the one or more HARQ ACK/NACK bits, wherein the control information bits comprising the one or more HARQ ACK/NACK bits and the appended SR bit are jointly encoded.
18. The WTRU of claim 13 , wherein a format associated with the PUCCH transmission is determined based on a number of control information bits to be included in the PUCCH transmission.
19. The WTRU of claim 13 , wherein the modulation of the control information bits is performed after scrambling the control information bits.
20. The WTRU of claim 13 , wherein the at least one orthogonal sequence is determined based on a length of the PUCCH transmission.
21. The WTRU of claim 13 , wherein the encoded control information bits are scrambled using a scrambling sequence, wherein the scrambling sequence is based on a WTRU's cell radio network temporary identifier (C-RNTI) or an identity of a cell in which the PUCCH transmission is sent.
22. The WTRU of claim 13 , wherein the processor is further configured to determine a number of control information bits to send, wherein the control information bits comprise hybrid automatic repeat request (HARQ) acknowledgement (ACK) bits, and the number of control information bits are determined based on a number of codewords received in the physical downlink shared channel (PDSCH) of one or more serving cells.
23. The WTRU of claim 13 , wherein the PUCCH transmission is sent over PUCCH resources, wherein the PUCCH resources comprise one or more single carrier frequency-division multiple access (SC-FDMA) symbols.
24. The WTRU of claim 13 , wherein the PUCCH transmission is a Discrete Fourier Transform (DFT) spread orthogonal frequency division multiplexing (OFDM) based PUCCH transmission.