A wireless sensor network based on the novel concept of an I-matrix to achieve high-precision lighting control

This paper presents an intelligent lighting control system based on a wireless sensor network applied to modern intelligent buildings. The appropriate intelligent lighting control plays a significant role in an energy-efficient and comfortable building environment. The novel concept of an illuminance matrix (I-matrix) is proposed and modeled as a precise expression of illuminance. This representation is more suitable for digital signal processing and high-precision lighting control. The I-matrix of a target working plane is obtained from several distributed photosensors using an RBF (Radial Basis Function) neural network. An optimization model is then constructed with a genetic algorithm to improve accuracy and reduce the number of sensors. Calculation results from a typical scene reveal that the proposed method is approximately 30-60% more accurate than conventional control practices. The application of the I-matrix is particularly essential for some places requiring a high quality of illuminance, such as an operation room, a cockpit, etc. As a criterion of illuminance quality, the I-matrix is a potential standard for high-quality lighting design, and opens new areas of research in lighting and human factors.