A new self-organizing map topology for real-time spectrum sensing and fast convergence

The paper presents a new modification of a self-organizing map topology to increase the speed of feature map convergence. The modification proposed in this paper is useful for real time spectrum sensing applications in which the SOM is used for classification tasks. Three alternative SOM topologies were tested and compared with the proposed topology modification. The number of epochs needed to ensure the convergence of feature maps was reduced by about 20 times using the proposed topology modification. An experimental investigation was performed using an SOM-based spectrum sensor on two radio bands with different spectral characteristics. The modified SOM topology showed not only a faster convergence, but also a better emission detection performance comparing to hexagonal, grid and rhombus topologies.