1. A method of generating reference signals for multiple layers by a User Equipment (UE), the method comprising: receiving a Cyclic Shift (CS) parameter from an evolved NodeB (eNodeB), the CS parameter comprising a 3-bit value; generating the reference signals for N layers based on the 3-bit value; and transmitting the generated reference signals to the eNodeB, wherein N is 2 or 4, and wherein the generating of the reference signals for the N layers comprises: applying a first Orthogonal Cover Code (OCC) for each of the N layers in response to a determination that the CS parameter is one of 011 indicating 4 as a CS parameter value of a first layer of the N layers and 100 indicating 2 as the CS parameter value of the first layer; and applying a second OCC for each of the N layers in response to a determination that the CS parameter is one of 101 indicating 8 as the CS parameter value of the first layer and 110 indicating 10 as the CS parameter value of the first layer.