Addressing the Control Channel Design Problem: OFDM-Based Transform Domain Communication System in Cognitive Radio

In cognitive radio, the design of an effective control channel must be based on a transmission scheme that satisfies two challenging requirements: long transmission range and low emission power. This paper proposes a novel transmission scheme that effectively satisfies these two requirements by combining an Orthogonal Frequency Division Multiplexing (OFDM) scheme with Transform Domain Communication System (TDCS) technology. The authors formulate, for the first time, a mathematical model of a Transform Domain Communication System (TDCS). Based on this model, they then design a new transmission scheme, named the OFDM-based TDCS for control message transmissions. The analytical and numerical analyses show that OFDM-based TDCS successfully satisfies both the transmission range and the emission power requirements of a control message transmission scheme for cognitive radio networks.