Search space design and use

1. A method for wireless communication at a wireless device, comprising:

monitoring, according to a search space configuration, a plurality of control channel elements (CCEs) of a subframe to detect a downlink control information (DCI) message for use by the wireless device, wherein the search space configuration comprises a first CCE carrying a first portion of the DCI message in a first symbol of the subframe and a second CCE carrying a second portion of the DCI message in a second symbol of the subframe; and

decoding, based at least in part on the monitoring, the DCI message.

2. The method of claim 1 , further comprising:

receiving an enabling indication of the search space configuration.

3. The method of claim 2 , wherein:

the enabling indication is received in at least one of a system information block (SIB) message, or a master information block (MIB) message, or a minimal system information block (MSIB) message.

4. The method of claim 1 , further comprising:

receiving a configuration message associated with the search space configuration.

5. The method of claim 4 , wherein:

the configuration message is received in a radio resource control (RRC) message.

6. The method of claim 1 , further comprising:

identifying, based at least in part on the search space configuration, an aggregation level associated with the plurality of CCEs.

7. The method of claim 1 , wherein:

the DCI message is repeated on the plurality of CCEs during different symbols, or

the DCI message is spread across the plurality of CCEs during different symbols.

8. A method for wireless communication, comprising:

selecting a search space configuration for transmission of a plurality of control channel elements (CCEs) to convey a downlink control information (DCI) message of a subframe, wherein the search space configuration comprises a first CCE carrying a first portion of the DCI message in a first symbol of the subframe and a second CCE carrying a second portion of the DCI message in a second symbol of the subframe; and

transmitting, based at least in part on the selecting, the DCI message.

9. The method of claim 8 , further comprising:

transmitting, based at least in part on the search space configuration, the plurality of CCEs during at least two symbols of a plurality of symbols used to convey the DCI message.

10. The method of claim 8 , further comprising:

transmitting an enabling indication of the search space configuration.

11. The method of claim 10 , wherein:

the enabling indication is transmitted in at least one of a system information block (SIB) message, or a master information block (MIB) message, or a minimal system information block (MSIB) message.

12. The method of claim 8 , further comprising:

transmitting a configuration message associated with the search space configuration.

13. The method of claim 12 , wherein:

the configuration message is transmitted in a radio resource control (RRC) message.

14. The method of claim 8 , further comprising:

selecting, based at least in part on the search space configuration, an aggregation level associated with the plurality of CCEs.

15. The method of claim 8 , wherein:

the DCI message is repeated on the plurality of CCEs during different symbols, or

the DCI message is spread across the plurality of CCEs during different symbols.

16. An apparatus for wireless communication, in a system comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to:

monitor, according to a search space configuration, a plurality of control channel elements (CCEs) of a subframe to detect a downlink control information (DCI) message for use by the apparatus, wherein the search space configuration comprises a first CCE carrying a first portion of the DCI message in a first symbol of the subframe and a second CCE carrying a second portion of the DCI message in a second symbol of the subframe; and

decode, based at least in part on the monitoring, the DCI message.

17. The apparatus of claim 16 , wherein the instructions are further executable by the processor to cause the apparatus to:

receive an enabling indication of the search space configuration.

18. The apparatus of claim 17 , wherein the enabling indication is received in at least one of a system information block (SIB) message, or a master information block (MIB) message, or a minimal system information block (MSIB) message.

19. An apparatus for wireless communication, in a system comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to:

select a search space configuration for transmission of a plurality of control channel elements (CCEs) to convey a downlink control information (DCI) message of a subframe, wherein the search space configuration comprises a first CCE carrying a first portion of the DCI message in a first symbol of the subframe and a second CCE carrying a second portion of the DCI message in a second symbol of the subframe;

transmit, based at least in part on the selecting, the DCI message.

20. The apparatus of claim 19 , wherein the instructions are further executable by the processor to:

transmit, based at least in part on the search space configuration, the plurality of CCEs during at least two symbols of a plurality of symbols used to convey the DCI message.

21. The apparatus of claim 19 , wherein the instructions are further executable by the processor to:

transmit an enabling indication of the search space configuration.

22. The apparatus of claim 21 , wherein the enabling indication is transmitted in at least one of a system information block (SIB) message, or a master information block (MIB) message, or a minimal system information block (MSIB) message.