1. Department of Electromechanical Engineering, Faculty of Engineering, University of Beira Interior, Rua Marquês d’Ávila e Bolama, 6201-001 Covilhã, Portugal
2. C-MAST-Centre for Mechanical and Aerospace Science and Technologies, 6201-001 Covilhã, Portugal
3. Instituto de Telecomunicações, Universidade da Beira Interior, 6201-001 Covilhã, Portugal