Free-space optics and high-speed RF for next generation networks $propagation measurements

Due to the consistently growing demand for high-speed wireless data access, future communication systems will necessarily have to enable real-time data access and high reliability as well as having superior weather resilience. Hybrid communication networks that integrate free space optics and RF systems are uniquely positioned to satisfy all the bandwidth, reliability, security and ´all-weather functionality´ requirements. Unfortunately, the technology has been growing at a pace that far exceeds our understanding of the effect of wireless propagation channels on these hybrid systems. The paper attempts to present some of the preliminary propagation measurement results for typical picocell scenarios and their impact on the design of hybrid communication systems. In addition to clear-sky and rain attenuation measurements, the paper presents frequency diversity measurements for fixed RF systems at the 38 GHz and 60 GHz frequency bands.