Nowadays the demand for indoor positioning is very high, but it is not a trivial task to find a solution for it. The electromagnetic waves in an indoor environment suffers from a lot of reflection from the walls and furniture, these effects are distorting the detected signals. The newest Bluetooth standard introduced a low energy data transfer mode, called “Bluetooth Smart”, this enables a low power, short range Beacon type system development. The Beacons advertising they ID and the Bluetooth Smart compatible devices, like a smartphone, can detect these signals and they can calculate their position form the ID and the received power.
The indoor reflections causes two-way propagation and because of this, the received power level can be different from the direct path propagation, and the distance can’t be determined easily. If we choose an optimal transmitter antenna we can reduce the effect of this. A directional antenna is a possible solution and with an ideal arrangement of the fixed transmitters we can further minimalize the effect of the reflections.
The research in my thesis is part of a research agreement between BME and General Electrics. I will design the above mentioned directional antenna which can be used in the Beacon system. I will also analyse an optimal antenna arrangement and use the results during the design. The measurements of the antennas will be in the University’s anechoic chamber.