Research On SFN Of DTTB Coverage Method

DTTB is the important part of Chinese radio and TV integrated coverage system. At present ,SFN is the best method of DTTB coverage.First of all, a good SFN coverage technology makes for the frequency planning.The second, SFN can solve the problem of blind spots to achieve better coverage rate by co-channel transmitting at multi-spots.Finally, SFN can reduce signal radiation and electromagnetic pollution, enhanced coverage uniformity and can be required to change coverage intent at any time.This article start with an analysis of SFN channel features,analyses several existing DTTB standard, composition of SFN system, key technologies, some problems and international SFN planning methods,and studies in depth the domestic SFN coverage methods.On this basis,I performance the SFN coverage experiment and specific implementation of the DVB-T, DTMB and CMMB in Hangzhou City.In the SFN implementation and experimental process of the three DTTB standard, through field tests, we analysed the pilot project covered and proposed a SFN optimization program, including: a reasonable means of distribution SFN station; choose the right SFN transfer mode; the reasonable SFN delay; the adjustment of antenna gain and field-type of base stations; the co-ordination of ERP of base stations. Above optimizing improved evidently the cover efficiency of the three DTTB standard.