Evaluation of transmitter frontends enabling digitally driven power amplifiers

Communication is a basic human need and as such it has undergone a variety of developments during history. Starting with the spoken word, which was later written eventually printed, the first development steps happened slowly. Finallly within the last centuries this development picked up speed. In this development most novel communication methods were first exploited by military applications and only later made available for public purpose. A first complex communication system were the nonelectronic semaphore telegraph links, which were first used for military purposes only and much later partly opened for commercial and civil usage. The same happened with electronic telegraph links and later with wireless communicaton techniques. But all these were opened sooner or later for commercial and civil applications.