VHF / UHF Filters and Multicouplers: Application of Air Resonators

Chapter 11

Multicouplers

11.1. Transmitter multicouplers (TX)

11.1.1. Choice of the technology

We now have, after the product-by-product analysis and descriptions made in the preceding chapters, all the elements necessary to define and produce complete coupling systems. Therefore, the question now is to decide what type of technology will be the best suited to the project in question, and this is probably the most important point, by its definitive nature, since once the system is chosen, it is practically impossible to change it after production has started. It is thus absolutely necessary to have a precise view, not only of the functionalities that will be implemented, but of the foreseeable or possible evolutions of the system, this last point being often forgotten by beginners. In fact, no radio network is fixed, because in addition to its intrinsic demands and specifications, it is subject to an eminently variable environment, due, for one thing, to the provisional and constantly revised character of the frequency allocations: it is always necessary to expect modifications, and thus strive to conceive a system that is as flexible and modifiable as possible.

No system is perfect, none can enjoy all the advantages, and from this results a great diversity of possible technical solutions whose number does not necessarily facilitate the task of the author of the specifications. Because it is absolutely necessary to have one set of specifications: while the major ordering parties ...