Modeling and Analysis of Cellular CDMA Forward Channel
Abstract
In this thesis, we develop the forward channel model for a DS-CDMA cellular system operating in a slow-flat Rayleigh fading and log normal shadowing environment, which incorporates the extended Hata model to predict median path loss. Forward error correction is integrated into the model by applying convolution encoding with soft-decision decoding. The worst-case probability of bit error for a mobile user at the edge of the center cell of a seven-cell cluster is developed using Gaussian approximation. In estimating the probability of bit error, we develop a statistical model, which approximates the sum of d multiplicative chi-square(two degrees of freedom)- log normal random variables as a multiplicative chi-square(with 2d degrees of freedom)-log normal random variable. Using this approximation, we examine the performance of the cellular system under a range of shadowing conditions, for various user capacities and with antenna sectoring as they compare with Monte Carlo simulated results. Next, we modify our worst-case performance analysis to accommodate users that are distributed in the cell according to a specified distribution and compare results with the worst-case performance. Finally, we introduce fast power control into the forward channel and explore system performance with power control under a range of operatng conditions as it compares with the fixed-power performance.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2001
- Accession Number
- ADA391598
Entities
People
- Jan E. Tighe
Organizations
- Naval Postgraduate School