A multiband system for improving indoor coverage of mobile communications in the GHz bands

In this paper a completely passive system is presented that allows to increase the signal levels inside buildings. Indeed, indoor coverage is usually problematic in modern high rise buildings [1]. Therefor, there is a need for a license-free system that can provide cheap assistance in shaping up the received signal levels. This system consists of (a) high gain broadband rooftop antenna(s), and one (or more) small multiband antenna(s) for the desired communication frequencies, connected to each other with low loss cables. It has been shown experimentally that terrain and building penetration attenuation can be compensated very effectively for only fractions of the cost of a base station in the building, and with an installation that requires no maintenance.