Optimization of spectrum usage for FM sound broadcasting in Tanzania

This research work sought to optimize the spectrum usage for FM sound broadcasting in Tanzania. The main argument was to establish whether the allocated spectrum for FM broadcasting was efficiently utilized hence propose an optimized plan. Considering the growing FM spectrum scarcity, the study was necessary in a perspective of balancing the demand and supply of FM spectrum available for allocation. The research design was quantitative having a sample size of one hundred and thirty (130) FM radio stations in four selected service areas of Dar es Salaam, Mwanza, Dodoma and Mbeya representing 79.7% of the targeted population. Assessment of the existing spectrum plans and actual usage was conducted, requirements for optimization were established, and an optimized spectrum plan was proposed by adopting a method of uniform fixed channel spacing of 400 kHz which provided additional FM channels. The study found that, the overall FM spectrum usage in service areas of Dodoma, Mwanza and Mbeya indicate a possibility of obtaining a total of seventy one (71) additional channels: twenty seven (27) channels in Dodoma, twenty two (22) channels in Mbeya and Mwanza respectively if spectrum plans were harmonized by re-planning. The study concludes that, as the demand in FM spectrum increases and the band become congested, efficient spectrum plans that can accommodate more users need to be adopted. However, digital audio broadcasting could be considered as the most preferred approach of optimizing FM spectrum usage especially in already saturated service areas like Dar es Salaam.