Method and Device for Generating Reference Signal in Cellular Mobile Communication System

1. A method of transmitting, by a base station, a reference signal in a mobile communication system, the method comprising: determining at least three scrambling variables, at least one of which is used for generating a demodulation reference signal sequence, comprising a first scrambling variable, a second scrambling variable, and a third scrambling variable, wherein the first scrambling variable, the second scrambling variable, and the third scrambling variable are different from each other; determining whether a demodulation reference signal is for more than or equal to 3-layer transmission; generating, if the demodulation reference signal is for 1 or 2 - layer transmission, the demodulation reference signal sequence using one of the first scrambling variable and the second scrambling variable; generating, if the demodulation reference signal is for more than or equal to 3-layer transmission, the demodulation reference signal sequence using the third scrambling variable; and transmitting the demodulation reference signal sequence through a corresponding antenna port.

2. The method of claim 1 , wherein the determining of the at least three scrambling variables comprises: identifying a terminal to be scheduled corresponding to the antenna port; and determining the third scrambling variable using a unique number of the terminal.

3. The method of claim 1 , further comprising: transmitting the third scrambling variable through a radio resource control (RRC) signal to the terminal.

4. A method of receiving, by a terminal, a reference signal in a mobile communication system, the method comprising: determining at least three scrambling variables, at least one of which is used for generating a demodulation reference signal sequence, comprising a first scrambling variable, a second scrambling variable, and a third scrambling variable, wherein the first scrambling variable, the second scrambling variable, and the third scrambling variable are different from each other; determining whether a demodulation reference signal is for more than or equal to 3-layer transmission; generating, if the demodulation reference signal is for 1 or 2 - layer transmission, the demodulation reference signal sequence using one of the first scrambling variable and the second scrambling variable; generating, if the demodulation reference signal is for more than or equal to 3-layer transmission, the demodulation reference signal sequence using the third scrambling variable; and receiving a demodulation reference signal using the demodulation reference signal sequence through a corresponding antenna port.

5. The method of claim 4 , wherein the determining of the at least three scrambling variables comprises: determining the third scrambling variable using a unique number of the terminal.

6. The method of claim 4 , wherein the determining of the at least three scrambling variables comprises: determining the third scrambling variable as a variable indicating the third scrambling variable received through a radio resource control (RRC) signal from a base station.

7. A base station for transmitting a reference signal in a mobile communication system, the base station comprising: a controller configured to: determine at least three scrambling variables, at least one of which is used for generating a demodulation reference signal sequence, comprising a first scrambling variable, a second scrambling variable, and a third scrambling variable, wherein the first scrambling variable, the second scrambling variable, and the third scrambling variable are different from each other, determine whether a demodulation reference signal is for more than or equal to 3-layer transmission, generate, if the demodulation reference signal is for 1 or 2 - layer transmission, the demodulation reference signal sequence using one of the first scrambling variable and the second scrambling variable, and generate, if the demodulation reference signal is for more than or equal to 3-layer transmission, the demodulation reference signal sequence using the third scrambling variable; and a transmitting unit configured to transmit the demodulation reference signal sequence through a corresponding antenna port.

8. The base station of claim 7 , wherein the controller identifies a user equipment (UE) to be scheduled corresponding to the antenna port, and determines the third scrambling variable using a unique number of the terminal.

9. The base station of claim 7 , wherein the transmitting unit transmits the third scrambling variable through a radio resource control (RRC) signal to the terminal.

10. A terminal for receiving a reference signal in a mobile communication system, the terminal comprising: a controller configured to: determine at least three scrambling variables, at least one of which is used for generating a demodulation reference signal sequence, comprising a first scrambling variable, a second scrambling variable, and a third scrambling variable, wherein the first scrambling variable, the second scrambling variable, and the third scrambling variable are different from each other, determining determine whether a demodulation reference signal is for more than or equal to 3-layer transmission, generate, if the demodulation reference signal is for 1 or 2 - layer transmission, the demodulation reference signal sequence using one of the first scrambling variable and the second scrambling variable, and generate, if the demodulation reference signal is for more than or equal to 3-layer transmission, the demodulation reference signal sequence using the third scrambling variable; and a receiving unit configured to receive a demodulation reference signal using the demodulation reference signal sequence through a corresponding antenna port.

11. The terminal of claim 10 , wherein the controller determines the third scrambling variable using a unique number of the terminal.

12. The terminal of claim 10 , wherein the controller determines the third scrambling variable as a variable indicating the third scrambling variable received through a radio resource control (RRC) signal from a base station.