[IEEE 2011 IEEE International Symposium on Broadband Multimedia Systems and Broadcasting (BMSB) - Metropolitan Area Nuremberg, Germany (2011.06.8-2011.06.10)] 2011 IEEE International Symposium on Broadband Multimedia Systems and Broadcasting (BMSB) - Field experiments on dual-polarized MIMO transmission with ultra-multilevel OFDM signals toward digital terrestrial broadcasting for the next generation