Arrangement and method for transmitting control information in wireless communication systems
Systems and methodologies are described that facilitate arrangement and transmission of control information in a wireless communication system. As described herein, a scheduled transmission of acknowledgement (ACK) signaling and channel quality information (CQI) signaling in a common subframe can be adapted for network implementations with limited link budget wherein ACK signaling is configured for repetition over multiple subframes to ensure a desired error rate level for the ACK signaling. To these ends, various aspects described herein facilitate modification of a coding rate applied to ACK signaling to be transmitted with data based on a repetition factor of the ACK signaling. Additionally and/or alternatively, various aspects described herein facilitate dropping of CQI signaling and transmission of only ACK signaling on subframes where CQI and ACK signaling are to be transmitted substantially simultaneously and ACK transmission is configured for repetition over multiple subframes.
1. A method for transmitting control information in a wireless communication system, comprising:
identifying acknowledgement (ACK) information and channel quality information (CQI) scheduled to be transmitted in a common subframe;
determining whether the ACK information is scheduled to be repeated across multiple subframes;
upon determining that the ACK information is not scheduled to be repeated across multiple subframes, transmitting the ACK information and the CQI in a common subframe; and
upon determining that the ACK information is scheduled to be repeated across multiple subframes, dropping the CQI from the common subframe and transmitting the ACK information without the CQI in the common subframe.
2. The method of claim 1 , further comprising:
identifying data to be transmitted with the ACK information and the CQI;
upon the determining that the ACK information is not scheduled to be repeated across multiple subframes, multiplexing at least one of the ACK information or the CQI with the identified data to create a multiplexed signal; and
transmitting the multiplexed signal.
3. The method of claim 2 , wherein the multiplexing comprises multiplexing at least one of the ACK information or the CQI with the identified data on resources reserved for transmission of data.
4. The method of claim 2 , wherein the multiplexing comprises:
selecting a coding rate based on the determination of whether the ACK information is scheduled to be repeated across multiple subframes; and
coding the ACK information using the selected coding rate.
5. The method of claim 1 , further comprising:
identifying one or more of ACK information or CQI to be transmitted without data; and
transmitting one or more of the ACK information or the CQI on resources reserved for control signaling.
6. The method of claim 5 , wherein the transmitting comprises jointly coding the identified ACK information and the identified CQI on resources reserved for the identified CQI upon the determining that the ACK information is not scheduled to be repeated across multiple subframes.
7. The method of claim 5 , wherein the transmitting comprises modulating one or more demodulation reference signals based on the identified ACK information upon the determining that the ACK information is not scheduled to be repeated across multiple subframes.
8. The method of claim 1 , wherein the transmitting the ACK information without the CQI comprises associating the ACK information with a first control channel element of an associated downlink assignment.
9. The method of claim 1 , further comprising modulating the ACK information using one or more of binary phase shift keying (BPSK) or quadrature phase shift keying (QPSK).
10. The method of claim 9 , wherein the modulating comprises selecting a modulation scheme to apply for the ACK information as a function of a number of streams for which ACK information is to be provided.
11. The method of claim 1 , further comprising transmitting one or more of ACK information, CQI, or data as a single-carrier waveform.
12. The method of claim 1 , wherein the CQI comprises one or more of a channel quality indication, a precoding matrix indication, or rank information.
13. A wireless communications apparatus, comprising:
a memory that stores data relating to acknowledgement (ACK)/negative acknowledgement (NAK) and channel quality information (CQI) signaling; and
a processor configured to determine that the ACK/NAK signaling and the CQI are scheduled to be transmitted in a common subframe, determine whether the ACK/NAK signaling is scheduled for repeat transmission over multiple subframes, wherein upon determining that the ACK/NAK signaling is not scheduled for repeat transmission over multiple subframes, said processor is further configured to transmit to the ACK information and the CQI in a common subframe, and wherein upon determining that the ACK/NAK signaling is scheduled for repeat transmission over multiple subframes, said processor is further configured to drop the CQI signaling and transmit only the ACK/NAK signaling in the common subframe.
14. The wireless communications apparatus of claim 13 , wherein the memory further stores data to be transmitted with the ACK/NAK and CQI signaling, and upon the determining that the ACK/NAK signaling is not scheduled for repeat transmission over multiple subframes, the processor is further configured to embed at least one of the ACK/NAK signaling or the CQI signaling with the data to be transmitted therewith.
15. The wireless communications apparatus of claim 14 , wherein the processor is further configured to communicate a signal resulting from the embedding of at least one of the ACK/NAK signaling or the CQI signaling with the data to be transmitted therewith on resources reserved for transmission of the data.
16. The wireless communications apparatus of claim 14 , wherein the processor is further configured to select a code rate for the ACK/NAK signaling based on the determination of whether the ACK/NAK signaling is scheduled for repeat transmission over multiple subframes and to embed the ACK/NAK signaling into the data to be transmitted therewith using the selected code rate.
17. The wireless communications apparatus of claim 13 , wherein upon the determining that the ACK/NAK signaling is not scheduled for repeat transmission over multiple subframes, the processor is further configured to communicate one or more of the ACK/NAK signaling or the CQI signaling on resources reserved for transmission of control signaling.
18. The wireless communications apparatus of claim 17 , wherein the processor is further configured to apply a joint coding scheme for the ACK/NAK and CQI signaling on resources reserved for transmission of CQI upon the determining that the ACK/NAK signaling is not scheduled for repeat transmission over multiple subframes.
19. The wireless communications apparatus of claim 17 , wherein the processor is further configured to modulate one or more reference signals in the subframe based on the ACK/NAK signaling upon the determining that the ACK/NAK signaling is not scheduled for repeat transmission over multiple subframes.
20. The wireless communications apparatus of claim 13 , wherein the processor is further configured to associate the ACK/NAK signaling with a first control channel element corresponding to an associated downlink assignment.
21. The wireless communications apparatus of claim 13 , wherein the processor is further configured to modulate the ACK/NAK signaling using one or more of binary phase shift keying (BPSK) or quadrature phase shift keying (QPSK).
22. The wireless communications apparatus of claim 21 , wherein the processor is further configured to select a modulation scheme to apply in modulating the ACK/NAK signaling based on a number of streams for which the wireless communications apparatus is configured to provide ACK/NAK signaling.
23. The wireless communications apparatus of claim 13 , wherein the data relating to CQI signaling stored by the memory comprises one or more of channel quality data, precoding matrix data, or rank information.
24. An apparatus that facilitates structuring of acknowledgement (ACK)/negative acknowledgement (NAK) information in a wireless communication system, the apparatus comprising:
means for identifying ACK/NAK information scheduled to be transmitted on a common subframe with channel quality information (CQI);
means for transmitting the ACK information and the CQI in a common subframe upon determining that the ACK/NAK information is not scheduled for repetition over a plurality of subframes; and
means for dropping the CQI from the common subframe and transmitting the ACK information without the CQI in the common subframe upon determining that the ACK/NAK information is configured for repetition over a plurality of subframes.
25. A computer program product, comprising:
a non-transitory computer-readable medium, comprising:
code for identifying acknowledgement (ACK) signaling scheduled to be transmitted simultaneously with channel quality information (CQI) signaling in a common subframe;
code for determining whether the ACK signaling is to be communicated in successive repeat transmissions;
upon determining that the ACK signaling is not to be communicated in successive repeat transmissions, code for transmitting the ACK information and the CQI in a common subframe; and
upon determining that the ACK signaling is to be communicated in successive repeat transmissions, code for performing one or more of decreasing a coding rate utilized for the ACK signaling or dropping the CQI signaling and transmitting the ACK signaling without the CQI signaling in the common subframe.