Empirical signal strength measurments over water

Abstract

Unmanned Surface Vehicles (USVs for short) are a breed of boats that are mostly touched by cybernetics engineers, where they model their control system and monitori their responses. By adding a sophisticated autopilot and way points for the vehicle to follow prior to its mission, it can become unmanned. For it to become unmanned, yet remotely controlled by man, wireless communication is needed. The company Maritime Robotics wanted to know what they could expect from their purchased radios, and how they could predict their range. Also diversity schemes providing a robust communication was an important issue to gain knowledge about. Both these subjects are discussed in this thesis, and empirical measurements from a test run performed in Trondheimsfjorden showed consistency with a theoretical two path model and the free space loss model, resulting in a path loss exponent somewhere between the two. The resulting path loss approximation might prove useful in planning the range of the company's USV's in the future, but several more tests should be run to validate the results further.