Outdoor RF spectral survey: A roadmap for ambient RF energy harvesting

In this paper, the results of outdoor RF spectral survey carried out in an urban area in Southern China are presented. The motivation of this work has been an attempt to record the dataset of ambient RF power radiated by the mobile base stations and Wi-Fi hotspots in the urban environment so as to select the frequency bands most suitable for the future ambient energy harvesting prototype design. RF spectrum survey was undertaken in the city center of Shunde, China, which is one of the most developed cities in Guangdong province. Typical places including shopping center square and a residential area have been considered in this survey. The ambient power level within the RF spectrum of 0.7 to 3 GHz has been measured to cover all the mobile frequency bands (2G, 3G and 4G) together with the 2.4 GHz Wi-Fi band. The survey results show that the available RF power levels of CDMA800, GSM900 and GSM1800 bands are the most promising for the ambient energy harvesting design and outdoor applications.