By Tom Holloran, Charter Communications
While DOCSIS software advances and video analog to digital conversions have dramatically increased the amount of video and data that can be delivered across a MHz of spectrum, annual IP data growth rates of 40-60% have made a 6 MHz EIA slot of spectrum an increasingly valuable commodity. Managing MSO product delivery on a fixed amount of RF spectrum has also become very challenging -- to the point that each slot of spectrum requires management like any other resource in the MSO supply chain.
This paper describes a set of algorithms and a supply chain process that can be used to identify the absolute minimum number of EIA slots that are required to meet the demand for any set of existing and future linear and switched video, digital audio, and IP data. Additionally, the algorithms can identify the minimum number of changes that are required to move content from existing spectrum locations into the identified minimum EIA slot allocation, and can maximize the placement preferences for content within defined ranges of spectrum.
The optimization algorithms of this paper are based on integer linear programming. However, they are implemented using a data-driven approach where tables containing engineering rules and location preferences drive all mathematical model generation. The underlying optimization system allows the modeler to treat content and EIA slots as supply chain commodities. Detailed changes to the optimization model can be made without in-depth knowledge or training in mathematical programming optimization techniques.
The algorithms and process contained in this paper are not limited in any way by the hardware and software required for implementation. Most mathematical optimization software packages that have a generalized integer programming capability can be used to implement the algorithms. A variety of software packages exist that can be used to visualize optimized RF Channel Maps. And a variety of software programming languages will facilitate the required functions of pattern generation and solution fitting.