Implementing Differential Distributed Orthogonal Space Time Block Coding Using Coefficient Vectors

A coefficient vector technique implemented on a differential distributed space time block coding (DDSTBC) scheme is presented in this paper to improve on the computation complexity of existing DDSTBC schemes. The full mapping scheme and differential technique for utilizing the co-efficient vectors in a two-relay cooperative network is presented and comparison is made between the proposed technique and the traditional unitary matrices based technique. Results obtained from the numerical and simulation analysis conducted, showed that the proposed method presents an improvement in terms of computation complexity and BER performance. The proposed scheme was extended to accommodate networks with four and eight relay nodes utilizing square-real orthogonal codes.