Random access method and related apparatus
A random access method and a related apparatus are disclosed. A user equipment receives first signaling from a base station through a physical downlink shared channel (PDSCH), and receives second signaling from the base station through a physical downlink control channel (PDCCH) or an enhanced physical downlink control channel (ePDCCH), where the first signaling includes a first time division duplexing TDD uplink-downlink configuration, and the second signaling includes a second TDD uplink-downlink configuration; the user equipment determines, according to the first TDD uplink-downlink configuration, an uplink subframe for sending a random access message; and the user equipment sends the random access message to the base station in the determined uplink subframe.
1. A method comprising:
receiving, by a user equipment, first signaling from a base station through a physical downlink shared channel (PDSCH), and receiving, by the user equipment, second signaling from the base station through a physical downlink control channel (PDCCH) or an enhanced physical downlink control channel (ePDCCH), wherein the first signaling comprises a first time division duplexing (TDD) uplink-downlink configuration, and the second signaling comprises a second TDD uplink-downlink configuration;
when both the first signaling comprising the first TDD uplink-downlink configuration and the second signaling comprising the second TDD uplink-downlink configuration are received by the user equipment, sending, by the user equipment, a random access message to the base station in a first uplink subframe within a first uplink subframe set of the first TDD uplink-downlink configuration, rather than according to the second TDD uplink-downlink configuration; and
when that both the first signaling comprising the first TDD uplink-downlink configuration and the second signaling comprising the second TDD uplink-downlink configuration are received by the user equipment, after accessing the base station, sending, by the user equipment, data in a second uplink subframe within a second uplink subframe set of the second TDD uplink-downlink configuration or receiving, by the user equipment, data in a first downlink subframe within a downlink subframe set of the second TDD uplink-downlink configuration.
2. The method according to claim 1 , wherein before the sending the random access message to the base station, further comprising:
sending, by the user equipment, a preamble to the base station on a third uplink subframe within the first uplink subframe set of the first TDD uplink-downlink configuration.
3. The method according to claim 2 , wherein before the sending a preamble to the base station, further comprising:
listening, by the user equipment on a second downlink subframe set of the first TDD uplink-downlink configuration, to a PDCCH Order or an ePDCCH Order sent by the base station.
4. The method according to claim 1 , wherein before the sending the random access message to the base station, further comprising:
listening, by the user equipment on a second downlink subframe set of the first TDD uplink-downlink configuration, to downlink control information (DCI) that is sent by the base station through the PDCCH or the ePDCCH and is scrambled by a random access-radio network temporary identifier (RA-RNTI).
5. The method according to claim 1 , wherein after the sending the random access message, further comprising:
receiving, by the user equipment on a third downlink subframe within a second downlink subframe set of the first TDD uplink-downlink configuration, a contention resolution message from the base station.
6. The method according to claim 1 , wherein the first signaling is a system information block.
7. An apparatus comprising:
a storage medium including executable instructions; and
a processor;
wherein the executable instructions, when executed by the processor, cause the apparatus to:
identify a first time division duplexing (TDD) uplink-downlink configuration from first signaling, the first signaling being received from a base station through a physical downlink shared channel (PDSCH), and identify a second TDD uplink-downlink configuration from second signaling, the second signaling being received from the base station through a physical downlink control channel (PDCCH) or an enhanced physical downlink control channel (ePDCCH);
when both the first signaling comprising the first TDD uplink-downlink configuration and the second signaling comprising the second TDD uplink-downlink configuration are received, send a random access message to the base station in a first uplink subframe within a first uplink subframe set of the first TDD uplink-downlink configuration, rather than according to the second TDD uplink-downlink configuration; and
when both the first signaling comprising the first TDD uplink-downlink configuration and the second signaling comprising the second TDD uplink-downlink configuration are received by the user equipment, send data in a second uplink subframe within a second uplink subframe set of the second TDD uplink-downlink configuration or detecting data in a first downlink subframe within a downlink subframe set of the second TDD uplink-downlink configuration.
8. The apparatus according to claim 7 , wherein the executable instructions, when executed by the processor, further cause the apparatus to:
before sending the random access message to the base station, cause the transmitter to send a preamble to the base station on a third uplink subframe within the first uplink subframe set of the first TDD uplink-downlink configuration.
9. The apparatus according to claim 8 , wherein the executable instructions, when executed by the processor, further cause the apparatus to:
before sending a preamble to the base station, listen, on a second downlink subframe set of the first TDD uplink-downlink configuration, to a PDCCH Order or an ePDCCH Order sent by the base station.
10. The apparatus according to claim 7 , wherein the executable instructions, when executed by the processor, further cause the apparatus to:
before sending the random access message to the base station, listen, on a second downlink subframe set of the first TDD uplink-downlink configuration, to downlink control information (DCI) that is sent by the base station through the PDCCH or the ePDCCH and is scrambled by a random access-radio network temporary identifier (RA-RNTI).
11. The apparatus according to claim 7 , wherein the executable instructions, when executed by the processor, further cause the apparatus to:
after sending the random access message, detecting, on a third downlink subframe within a second downlink subframe set of the first TDD uplink-downlink configuration, a contention resolution message from the base station.
12. The apparatus according to claim 7 , wherein the first signaling is a system information block.
13. A non-transitory computer-readable medium storing computer instructions that, when executed by one or more hardware processors, cause the one or more hardware processors to:
receive first signaling through a physical downlink shared channel (PDSCH), and receive second signaling through a physical downlink control channel (PDCCH) or an enhanced physical downlink control channel (ePDCCH), wherein the first signaling comprises a first time division duplexing (TDD) uplink-downlink configuration, and the second signaling comprises a second TDD uplink-downlink configuration;
when both the first signaling comprising the first TDD uplink-downlink configuration and the second signaling comprising the second TDD uplink-downlink configuration are received by the user equipment, send a random access message in a first uplink subframe within a first uplink subframe set of the first TDD uplink-downlink configuration, rather than according to the second TDD uplink-downlink configuration; and
when both the first signaling comprising the first TDD uplink-downlink configuration and the second signaling comprising the second TDD uplink-downlink configuration are received by the user equipment, send data in a second uplink subframe within a second uplink subframe set of the second TDD uplink-downlink configuration or receive data in a first downlink subframe within a downlink subframe set of the second TDD uplink-downlink configuration.
14. The non-transitory computer-readable medium according to claim 13 , wherein the computer instructions further cause the one or more hardware processors to:
before sending the random access message, send a preamble on a third uplink subframe within the first uplink subframe set of the first TDD uplink-downlink configuration.
15. The non-transitory computer-readable medium according to claim 14 , wherein the computer instructions further cause the one or more hardware processors to:
before send the preamble, listen to a PDCCH Order or an ePDCCH Order on a second downlink subframe set of the first TDD uplink-downlink configuration.
16. The non-transitory computer-readable medium according to claim 14 , wherein the computer instructions further cause the one or more hardware processors to:
before sending the random access message, listen, on a second downlink subframe set of the first TDD uplink-downlink configuration, to downlink control information (DCI) that is sent by the base station through the PDCCH or the ePDCCH and is scrambled by a random access-radio network temporary identifier (RA-RNTI).
17. The non-transitory computer-readable medium according to claim 13 , wherein the computer instructions further cause the one or more hardware processors to:
after sending the random access message, receive a contention resolution message on a third downlink subframe within a second downlink subframe set of the first TDD uplink-downlink configuration.
18. The non-transitory computer-readable medium according to claim 13 , wherein the first signaling is a system information block.