Analytical BER Computation for MC CDMA System with Iterative HIC Receiver

The existing mobile communication system suffer from problems like frequency selective fading and multi-path signals, multiple access interference due to imperfect nonorthogonal codes and narrow band interference due to coexisting systems. Multi-carrier Code Division Multiple Access (MC-CDMA) technique can combat these problems efficiently owing to its inherent properties. The objective of this paper is to suggest an optimum receiver for the MC-CDMA system by computing the BER of different receivers. Since multi-user interference degrades the performance of the receiver, interference cancellation technique is to be incorporated in the receiver. As Parallel Interference Cancellation (PIC) is faster, less efficient and Successive Interference Cancellation (SIC) scheme is slow but efficient a Hybrid Interference Cancellation (HIC) scheme is arrived at combining the advantages of these two schemes. The hybrid scheme is simple, faster and reliable. The performance of the receiver is studied by comparing with the BER of a detector without interference cancellation. Improvements in performance of parallel interference cancellation can be achieved by using multiple stages of the cancellation unit. Similarly performance of HIC receiver can also be improved if the PIC part of HIC is made iterative. Computation results imply iterative HIC outperforms iterative PIC compared in terms of computational L. Nithyanandan and P. Dananjayan F F 2 International Journal of Aerospace and Electronics Systems, Vol. 1, No. 1-2, Jan-Dec 2011 complexity and error performance and hence will be an optimal choice for MC CDMA reception.