Performance evaluation and comparison of pre-equalizer for rain attenuation channels in a B-WLL uplink system

In this paper, the performance of a pre-equalization technique which can be applicable for the B-WLL uplink is evaluated and compared to post-equalization under three kinds of rain attenuation channels such as rain, intermittent light rain and thundershower. The comparison of two algorithms (LMS and RLS) is investigated in the context of channel models and the length of training sequence. From the simulation results, it is shown that the post-equalization outperforms only at quite good channel conditions such as AWGN, while the pre-equalization can guarantee better BER performance at all channel conditions, especially performance gain increases as the severity of the channel increases. It is concluded that the pre-equalizer using the LMS algorithm is preferable at delay-tolerant situations where the complexity of the algorithm is not a strict factor, while one using RLS is suitable for fast burst transmission with a relatively short training sequence.