Outdoor Signal Strength Measurement at TV Band and ISM Band in Otaniemi Campus

Abstract

TV white space technology is being intensively researched as it offers a solution that allows secondary usage of the local unused TV channels on a non-interfering basis to achieve a high spectrum efficiency. This thesis studies the difference between TV band and ISM band outdoor propagation characteristics in Otaniemi campus area. The study aims to verify if the TV band signal could extend the service range with less transmitting power and if it has better propagation and building penetration characteristics than ISM band signal. As part of our research we first perform a state-of-the-art review on TV white space technology including its features, promising applications and the evolution of regulation and standardisation. Then the measurement campaign set up is demonstrated based on the architecture of transmitter and receiver, the signal source and the antenna. Measurements were carried out by two transmitter locations and 49 receiver locations over distances up to 2.6 kilometers. The 'tcpdump' tool in OpenWrt system that embedded in Dlink box was used to measure the received signal characteristics for both bands. The measurement results have been compared with the existing empirical propagation models and the differences between the model predicted and field measured data have been analysed. The results could be considered as a good basis for further theoretical research as well as for practical application research.