A possible frequency planning method and related model calculations for the sharing of VHF band II (87.5-108 MHz) between FM and DAB (digital audio broadcast) systems

A frequency planning method is proposed that is based on regular lattices derived from factorial rhombic numbers. It is shown theoretically that the spectrum efficiency can be improved by about 30% in comparison to existing broadcast networks. This implies less stringent constraints for frequency multiplexing at the transmitter sites. A frequency plan and model calculations of the network coverage are given for a test area. It is shown that the capacity of the VHF spectrum is sufficient to introduce DAB yet still broadcast the same amount of existing FM programs.<
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