Framing, scheduling, and synchronization in wireless systems
A WTRU may receive downlink control information (DCI) indicating a start of a frame. The DCI may be received on a control channel, such as the Physical Downlink Control Channel (PDCCH) from an eNB, base station, AP, or other infrastructure equipment operating in a wireless communications system. The WTRU may decode the DCI and may determine a transmit time interval (TTI) duration, which may be expressed in terms of an integer number of basic time intervals (BTIs). The WTRU may determine a downlink (DL) transmission portion and assignment and an uplink (UL) transmission portion and UL grant based on the received DCI. Additionally, the WTRU may determine the start of the UL portion based on an offset (t offset ). The WTRU may receive data in a DL portion of the frame and may transmit in an UL portion of the frame based on the determined UL grant and TTI duration.
1. A method comprising:
receiving, by a wireless transmit/receive unit (WTRU), a downlink control information (DCI) in a physical downlink control channel (PDCCH) transmission, the DCI comprising an indication of a start symbol timing for a downlink transmission, an indication of a number of symbols for the downlink transmission, an indication of a time offset for an uplink transmission, and an indication of resources for the uplink transmission;
receiving, by the WTRU, the downlink transmission based on the start symbol timing and the number of symbols indicated in the DCI; and
transmitting, by the WTRU, the uplink transmission using the time offset and the resources indicated by the DCI.
2. The method of claim 1 , wherein the uplink transmission includes hybrid automatic repeat request (HARQ) information.
3. The method of claim 1 , wherein the uplink transmission includes uplink control information (UCI).
4. The method of claim 1 , further comprising receiving configuration information indicating a set of resources for uplink control information (UCI).
5. The method of claim 1 , further comprising, interrupting the uplink transmission so that the uplink transmission does not occur in symbols indicated by the start symbol timing and the number of symbols indicated in the DCI for a set of resources.
6. The method of claim 1 , wherein the DCI comprises an indication of a subcarrier spacing for the downlink transmission.
7. The method of claim 6 , wherein the subcarrier spacing corresponds to a spectrum operating mode (SOM).
8. A wireless transmit/receive unit (WTRU) comprising:
a receiver;
a transmitter; and
a processor,
the receiver and the processor configured to:
receive a downlink control information (DCI) in a physical downlink control channel (PDCCH) transmission, the DCI comprising an indication of a start symbol timing for a downlink transmission, an indication of a number of symbols for the downlink transmission, an indication of a time offset for an uplink transmission, and an indication of resources for the uplink transmission; and
receive the downlink transmission based on the start symbol timing and the number of symbols indicated in the DCI; and
the transmitter and the processor configured to transmit the uplink transmission using the time offset and the resources indicated by the DCI.
9. The WTRU of claim 8 , wherein the uplink transmission includes hybrid automatic repeat request (HARQ) information.
10. The WTRU of claim 8 , wherein the uplink transmission includes uplink control information (UCI).
11. The WTRU of claim 8 , wherein the receiver and the processor are further configured to receive configuration information indicating a set of resources for uplink control information (UCI).
12. The WTRU of claim 8 , wherein the processor and the transmitter are further configured to interrupt the uplink transmission so that the uplink transmission does not occur in symbols indicated by the start symbol timing and the number of symbols indicated in the DCI for a set of resources.
13. The WTRU of claim 8 , wherein the DCI comprises an indication of a subcarrier spacing associated with the downlink transmission.
14. The WTRU of claim 13 , wherein the subcarrier spacing corresponds to a spectrum operating mode (SOM).
15. The WTRU of claim 8 , wherein a field comprised in the DCI provides the indication of the start symbol for the downlink transmission and the indication of the number of symbols for the downlink transmission.
16. A base station comprising:
a receiver;
a transmitter; and
a processor,
the transmitter and the processor configured to:
transmit a downlink control information (DCI) in a physical downlink control channel (PDCCH) transmission, the DCI comprising an indication of a start symbol timing for a downlink transmission, an indication of a number of symbols for the downlink transmission, an indication of a time offset for an uplink transmission, and an indication of resources for the uplink transmission; and
transmit the downlink transmission based on the start symbol timing and the number of symbols indicated in the DCI; and
the receiver and the processor configured to receive the uplink transmission using the time offset and the resources indicated by the DCI.
17. The base station of claim 16 , wherein the uplink transmission includes hybrid automatic repeat request (HARQ) information.
18. The base station of claim 16 , wherein the uplink transmission includes uplink control information (UCI).
19. The base station of claim 16 , wherein the transmitter and the processor are further configured to transmit configuration information indicating a set of resources for uplink control information (UCI).
20. The base station of claim 16 , wherein the processor and the receiver are further configured to interrupt reception of the uplink transmission so that the uplink transmission does not occur in symbols indicated by the start symbol timing and the number of symbols indicated in the DCI for a set of resources.