Frequency Planning Synthesis and new Concepts
Compiling Frequency Allocation Plans . . .
The purpose of frequency planning is the provision of frequencies for all reception points such that broadcasting coverage is sufficiently extensive and of high quality. Frequency-allocation plans stipulate the rights to use a frequency in a specified area. The stipulated parameters for mutual interference must not be exceeded by broadcasting services and broadcast content transmitted on the same frequency or on neighbouring frequencies.
Examples of allocation plans include T-DAB frequency plans (Wiesbaden in 1995 and Maastricht in 2002) as well as the plan compiled in Geneva in 2006, which regulates the digital broadcasting landscape in the frequency bands III and IV/V.
. . . a Matter of Combinatorial Optimisation
Frequency-allocation plans cover large geographical areas and thus typically govern thousands of instances of frequency usage. The synthesis of allocation plans compatible with interference thus presents a complex mission requiring combinatorial optimisation. IRT addresses such tasks by relying on modern and effective methods of stochastic optimisation. We also enhance these methods, which are ideally suited for synthesising modern frequency-allotment plans and conventional frequency-assignment plans for a large number of broadcasting services on the basis of cellular or broadcasting networks.
The Supplementing of Existing Frequency Allocation Plans
The synthesis of allocation plans not only results in the creation of new frequency plans, but also the addition of supplementary frequency use to existing plans. The same methods are employed in this case as during the compilation of new allocation plans. Thanks to modern planning tools and years of experience, IRT has the expertise necessary for investigating and demonstrating additional options for frequency utilisation in existing plans.
New Concepts in Network Structure
The growing demand for spectrum access has in recent years spawned new concepts which facilitate optimum spectrum use. Single frequency networks (SFNs), for example, offer broadcasters the unique possibility of utilising spectra far more efficiently. In terms of frequency planning, SFN technology is similar to the principle of allotment. The implementation of frequency-allotment plans stipulated in the GE06 agreement offers network operators considerable latitude to design their networks as they wish. Ultimately, these new possibilities constitute a significant step toward more flexible use of spectra.
IRT played a significant role in ensuring that SFN and allotment concepts were included in RRC-06 planning principles. Allotment planning and SFNs laid the foundation for realising an ambitious goal: the creation of seven wide-area coverage sectors for digital television in Germany.
New Approaches to Spectrum Allocation
IRT studies new concepts such as SDR (Software-Defined Radio), LBT (Listen Before Talk), DFS (Dynamic Frequency Selection) and cognitive radio before determining their suitability for broadcasting applications. Our experts also analyse interactions between broadcasting technology and new systems based on one of these concepts.
