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Single Frequency Network measurement for digital video network

Single Frequency Network (SFN) is widely deployed for digital video systems, not only for classical Single Input Single Output (SISO) systems like DVB-T, but also for the latest Multiple Input Single Output (MISO) DVB-T2 system. In this paper, we propose one scheme to measure the echo power and echo delay accurately in an SFN with OFDM technology, for both pre-echoes and post-echoes, even with long delay which may be outside guard interval (GI) of an OFDM symbol. The measurement results would be used for network optimization. Lab and field tests are carried out to verify the algorithm for both SISO DVB-T SFN and MISO DVB-T2 SFN. Also results for SISO-SFN and MISO-SFN measurement are compared, which is helpful for DVB-T2 network deployment.