Millimeter-wave Active Imaging Using Multiple Frequencies with Complex-Valued Self-Organizing Map Image Processing

Millimeter-wave possesses high penetrability and high directivity. In security imaging, we use these features to discover weapons concealed under clothes. We previously proposed a millimeter-wave imaging system for moving targets consisting of one-dimensional array antenna, parallel front-end and complex-valued self-organizing map (CSOM) to deal with complex texture. This system observes targets at multiple modulation frequencies. In this paper, we investigate reduction of the measurement time by reducing measurement frequency points. Experiments examine the trade-off between the number and visualization quality.