Abstract: The design and development of a Wireless Sensor Network (WSN) on an indoor scenario, where multipath propagation has special relevance, is often a difficult task that requires a long and tedious fieldwork that is not reusable later. This paper focuses on the validation of 3D Ray Launching simulation as an efficient method for reducing the time and effort required to design and develop a WSN on a complex indoor scenario, which can later be employed for different applications. Using a well tested deterministic method which offers reliable results, the most suitable antenna distribution and consequently a homogeneous power distribution could be achieved easily for different places and topologies. In this work the radioplanning procedure is validated in a prototype of a WSN Mobile Ad-Hoc Network (MANET), implementing a chain configuration deployed in a real indoor scenario, which is the entire floor of a university department, providing assessment on radio level, signal quality and power consumption. The use of deterministic tools in WSN deployment phases can aid in providing optimal layouts in terms of coverage, capacity and energy efficiency of the network, therefore the power distribution, intra-system interference maps and power delay profiles are calculated based on the simulation results. Finally, the validity of the simulation is proved comparing the obtained power level results and the RSSI level provided by WSN. The output of the proposed wireless systems planning process leads to energy efficient as well as to capacity enhanced network designs.