Planning Factors for Digital Local Broadcasting in the 26 MHz Band

The 26 MHz band is currently allocated for international broadcasting by means of the ionospheric propagation. However, sky waves are strongly dependent on the ionosphere conditions and signal reception is not always possible. As a consequence, this HF frequency range is scarcely utilized and an optimization of its use is required. The DRM (Digital Radio Mondiale) standard provides enough robustness to enable reliable audio reception taking advantage of the ground wave propagation at these frequencies. According to this, local coverage is viable in this part of the spectrum, as proved the field trials and studies carried out in the last years. Nevertheless, it is still necessary to establish the general guidelines for the set up and consolidation of the corresponding digital networks. Thus, the planning factors and procedures for digital local broadcasting services in the 26 MHz band are defined in this paper, along with reference parameter values and recommended system configurations for this new application.