SFN-SISO and SFN-MISO Gain Performance Analysis for DVB-T2 Network Planning

In DVB-T2, the single frequency network (SFN) mode is an attractive planning alternative to the well-known multiple frequency network (MFN) mode. SFN networks provide augmented spectrum efficiency as well as a quality of service improvement due to a more homogeneous distribution of the received signal strength over the coverage area. Nevertheless, some areas will also show degradation in practice. In order to improve the performance of the SFN operation, the second generation broadcast system DVB-T2 standard incorporates multiple input single output (MISO) antenna diversity mechanisms. Based on empirical analyses and system level simulations, this paper analyzes the key factors affecting the SFN operation. This paper analyzes SFN effects as well as the corresponding MISO gain margins for commercial and custom software defined radio (SDR) receiver implementations. The results show that the MISO gain is restricted only to the overlapping areas of an SFN where a small power imbalance between MISO groups, is present being the achievable MISO gain higher with high modulation code rates. The results also address that degradation arises in the non-overlapping regions of an SFN. This paper provides also updated C/N thresholds for DVB-T2 network planning.