1. Department of Electronics and Computer Science, University of Santiago de Compostela, Campus Sur s/n, 15782-Santiago de Compostela, Spain. Email: b.blanco@ieee.org
2. Department of Electronics and Computer Science, University of Santiago de Compostela, Campus Sur s/n, 15782-Santiago de Compostela, Spain. Email: paula@dec.usc.es
3. Department of Electronics and Computer Science, University of Santiago de Compostela, Campus Sur s/n, 15782-Santiago de Compostela, Spain. Email: diego@dec.usc.es
4. Fraunhofer Institut fuer Integrierte Schaltungen, Am Wolfsmantel 33, 91058 Erlangen, Germany. Email: ern@iis.fraunhofer.de
5. Fraunhofer Institut fuer Integrierte Schaltungen, Am Wolfsmantel 33, 91058 Erlangen, Germany. Email: nbh@iis.fraunhofer.de
6. Fraunhofer Institut fuer Integrierte Schaltungen, Am Wolfsmantel 33, 91058 Erlangen, Germany. Email: johann.hauer@iis.fraunhofer.de