Fuzzy-logic Based Path Loss Models for Metropolitan Environment

摘要

The increasing demand for radio channels, which emanates from the explosive requirement for wireless services in a metropolitan environment is one of the major challenges facing the path loss propagation prediction. However, this prediction is necessary for link budget and in the determination of the coverage area of a particular base station. Therefore, in this paper, a fuzzy-logic based path loss prediction model is proposed for accurate link budget and optimal coverage determination. Also, a drive test is conducted and data were collected for non urban, urban, suburban, ex-urban, dense-urban, micro-urban and peri urban areas in Lagos metropolitan environment for training the proposed model. Network parameters were varied during the process of performance evaluation for the 900MHz and 1800MHz bands. Results show that the mean path loss for different environments is higher for the 900MHz band compared with 1800MHz band and this shows that propagation in the 900MHz environment is characterised with more challenges and dynamic propagation conditions than in 1800MHz. Additionally, the urban environment gives the highest value for the constant offset being 60dB for 900MHz but the ex-urban environment has a constant offset of 64dB in 1800MHz.