3. Development of multimodal fiber optic radio technology

3.1 Applications and topologies

Fiber radio systems are designed to distribute microwave and millimeter-wave radio frequency signals inside confined spaces such as buildings. Their primary purpose is to replace the radio channel, which is deficient in these environments. Unlike digital signals, the spectral width of the signals handled by these systems can be relatively small (a few tens of kHz for GSM applications) and can reach 500 MHz for broadband wireless applications. The main advantage of these techniques is their ability to reach radio fading zones, in which case several access points are needed to cover such an area, which is generally less than a kilometer in perimeter. This concept can be applied to picocells with perimeters of the order of a hundred meters. In practical...