1 research outputs found
Spreading Codes for Multiuser Estimation in Non Coherent and Non Cooperative Environments
The need for a more efficient and reliable use of
available radio resources has led to the developement of Spread
Spectrum based communication networks, like WCDMA. Even
though the Spread Spectrum signals are inherently robust, and
provide significant level of security, it has been shown that the use
of interference suppression techniques can result in a substantial
performance improvement. This paper proposes an overview of
interference suppression techniques used in combination with
different sets of spreading codes. The focus of the paper is
on Direct Sequence SS systems, and on the choice of proper
spreading codes, in a blind asynchronous environment. Particular
attention is devoted to analyzing the performance of spreading
codes based on their cross correlation properties, in a multiple
users scenario. Eigenvalue estimation and Maximum Likelihood
estimation techniques are used to evaluate the robustness of the
system, in the presence of Additive White Gaussian Noise