Cost 231 Model may refer to one of two outdoor radio propagation models for applications in urban areas at 900 and 1800 MHz bands that were developed by the European COST Action 231. This document is one guideline for you to plan and design the radio transmission for GSM900&1800.
The COST programs are to a great extent freely available. Some respect to the Europeans for this work is better shown by not taking advantage in any way. The following links describe all reports for COST 231, including the final report as well as some MATLAB implementations.
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