Method of transmitting scheduling information in TDD system
A method of transmitting scheduling information in time-division-duplex (TDD) system is provided. The method comprises configuring a radio frame, the radio frame comprising at least one downlink subframe and at least one uplink subframe, wherein a downlink subframe is reserved for downlink transmission and an uplink subframe is reserved for uplink transmission, and transmitting scheduling information on a downlink control channel in a downlink subframe, the scheduling information comprising an uplink indicator and uplink resource assignment, the uplink indicator indicating which at least one uplink subframe the uplink resource assignment is valid for. Data can be efficiently transmitted by using an uplink indicator which indicates a specific location of a subframe.
1. A method of transmitting, by a base station, scheduling information in a time-division-duplex (TDD) mobile communication system using a plurality of radio frames, each including downlink subframes reserved for downlink and uplink subframes reserved for uplink, the method comprising:
transmitting, to a user equipment, scheduling information on a downlink control channel within a downlink subframe in a radio frame, the scheduling information comprising an uplink indicator and an uplink resource assignment,
wherein the uplink indicator identifies a position of at least one uplink subframe for which an uplink resource is assigned from a position of the downlink subframe,
wherein the uplink resource assignment identifies a radio resource to be used for uplink data transmission in the at least one uplink subframe, and
wherein a number of downlink subframes in the radio frame is less than a number of uplink subframes in the radio frame.
2. The method of claim 1 , further comprising transmitting configuration information for the radio frame, the configuration information indicating for each subframe in the radio frame whether it is reserved for uplink or downlink.
3. The method of claim 2 , wherein the configuration information indicates configuration 0 of the table below:
Con-
Switch-point
Subframe number
figuration
periodicity
0
1
2
3
4
5
6
7
8
9
0
5 ms
D
S
U
U
U
D
S
U
U
U
1
5 ms
D
S
U
U
D
D
S
U
U
D
2
5 ms
D
S
U
D
D
D
S
U
D
D
3
10 ms
D
S
U
U
U
D
D
D
D
D
4
10 ms
D
S
U
U
D
D
D
D
D
D
5
10 ms
D
S
U
D
D
D
D
D
D
D
6
5 ms
D
S
U
U
U
D
S
U
U
D
where ‘D’ denotes a subframe used for downlink transmission, ‘U’ denotes a subframe used for uplink transmission, and ‘S’ denotes a special subframe that is used for a special purpose.
4. The method of claim 1 , wherein the downlink control channel is a physical downlink control channel (PDCCH).
5. The method of claim 1 , wherein a total bit number of the uplink indicator is 2.
6. The method of claim 1 , wherein the at least one uplink subframe is two consecutive uplink subframes.
7. The method of claim 1 , further comprising receiving, from the user equipment, mobile communication data in the at least one uplink subframe.
8. A method of transmitting, by a user equipment, data in a time-division-duplex (TDD) mobile communication system using a plurality of radio frames, each including downlink subframes reserved for downlink and uplink subframes reserved for uplink, the method comprising:
receiving, from a base station, scheduling information, including an uplink indicator and an uplink resource assignment, on a downlink control channel within a downlink subframe in a radio frame, wherein the uplink indicator identifies a position of at least one uplink subframe for which an uplink resource is assigned from a position of the downlink subframe; and
transmitting mobile communication data to the base station in the at least one uplink subframe,
wherein the uplink resource assignment identifies a radio resource to be used for uplink data transmission in the at least one uplink subframe, and
wherein a number of downlink subframes in the radio frame is less than a number of uplink subframes in the radio frame.
9. The method of claim 8 , wherein the downlink control channel is a physical downlink control channel (PDCCH).
10. The method of claim 8 further comprising receiving configuration information for the radio frame, the configuration information indicating for each subframe in the radio frame whether it is reserved for uplink or downlink.
11. The method of claim 10 , wherein the configuration information indicates configuration 0 of the table below:
Con-
Switch-point
Subframe number
figuration
periodicity
0
1
2
3
4
5
6
7
8
9
0
5 ms
D
S
U
U
U
D
S
U
U
U
1
5 ms
D
S
U
U
D
D
S
U
U
D
2
5 ms
D
S
U
D
D
D
S
U
D
D
3
10 ms
D
S
U
U
U
D
D
D
D
D
4
10 ms
D
S
U
U
D
D
D
D
D
D
5
10 ms
D
S
U
D
D
D
D
D
D
D
6
5 ms
D
S
U
U
U
D
S
U
U
D
where ‘D’ denotes a subframe used for downlink transmission, ‘U’ denotes a subframe used for uplink transmission, and ‘S’ denotes a special subframe that is used for a special purpose.
12. The method of claim 8 , wherein a total bit number of the uplink indicator is 2.
13. The method of claim 8 , wherein the at least one uplink subframe is two consecutive uplink subframes.