Narrow Results

In this paper, a performance comparison of SC-CDMA and MC-CDMA systems in Rayleigh fading channels is presented in the asynchronous uplink. Both coded and uncoded systems are considered as the uncoded systems show the behavior of the different signal models, the coded systems provide a realistic scenario for comparison. MC-CDMA is used in the frequency spreading approach. Serial concatenated coding (SCC) of a convolutional, a Walsh-Hadamard and a repetition code is used for the comparison of the coded systems. Iterative decoding is applied.

The bit error probability for MC-CDMA and SC-CDMA is calculated for the uncoded systems and a union bound for the coded systems is given. Potentials to meliorate the occurring disadvantages of both system designs are presented and differences in multi-user environments are demonstrated.

Asymptotic expansions are derived for the Laplace convolution (f*g)(x) as x → ∞, where f and g have asymptotic power series representation in descending powers of t. Bounds are also constructed for the error terms associated with these expansions. Similar results are given for the convolution integrals

as x → ∞. These results can be used in the study of asymptotic solutions to the renewal equation and the Wiener-Hopf equations.