What are you looking to do in regards to coverage areas? Esri and its partners have solutions for RF engineering, coverage processing and mapping, and management of wireless structures and assets.
In case you want to perform the analysis that is required to create the coverage maps, this is offered by partners of Esri. If you scroll down on the page you mentioned (GIS for Telecommunications | Overview ) you will see a list of partners like Cellular Expert that offers software to do network coverage prediction, drive-test data analysis and model calibration, frequency allocation and more.
Thanks, I have tried contacting Cellular-Expert, I have sent three contact us mails to Cellular-Expert but no reply from them.Please do you have any Cellular-E PR I can contact directly?