Radio topology design with slow frequency hopping for interference limited digital cellular systems

A simulation approach is adopted to evaluate the performance of cellular systems with slow frequency hopping. The simulation incorporates a model for the fading channel which includes path loss, shadow, and fast fading as well as models for power control and discontinuous transmission. Hopping sequences as defined for the GSM (Group Special Mobile) system are used. Results for both the hopped and nonhopped cases are presented in terms of frame erasure rates, outage probabilities, and distributions of mean wanted to mean interference ratios. In particular, 9- and 12-cell reuse clusters with and without hopping are compared. The results obtained confirm that a reduction in outage probability and a resultant increase in capacity can be obtained with slow frequency hopping. It is shown that, as the number of hopped frequencies increases to about five, the benefit of hopping steadily increases. Hopping over more than five frequencies provides only negligible additional gain