A cognitive radio indoor HDTV multi-vision system in the TV white spaces

Wireless multi-vision applications for home entertainment are becoming an important trend in consumer electronics domain. Currently, most of the existing applications rely on the 802.11g/n standards, capable to seamlessly stream HD video contents. These standards are operating in the license-free ISM band, which, due to the rapid revolution in wireless communication in past years, is becoming overexploited and experiences serious coexistence problems. The spectrum overcrowding in the free bands puts in a new light the VHF and UHF bands that are currently seen as a promising alternative spectrum resource, especially in the perspective of the worldwide switchover from analog to digital TV and in the light of the new emerging dynamic spectrum access techniques. Within this framework, this paper presents an unlicensed cognitive radio indoor multi-vision system operating in the UHF TV band for short-range indoor transmission of high definition TV contents. The system relies on a combined exclusive approach of spectrum sensing and geo-location database and is compliant with the DVB-T2 broadcasting standard. A proof-of-concept digital terrestrial television (DTT) compliant prototype has been implemented on a test-bed based on commercial DTT receivers in combination with software defined radio hardware devices. Extended measurements performed in a real indoor environment assessed the feasibility of the proposed system in terms of coverage and protection of the incumbent users.