Abstract

The object of this diploma thesis was to develop a practical power amplifier for the radio frequency band at UHF. The range reaches from 440MHz to 470MHz. The required ampli-fier had to be designed for a new generation of taxi-radios. The input power of the ampli-fier is constant at 10mW. It is intended to increase the output power to more than 10W, which improves both, the range and the quality of the reception.

It is necessary to design the amplifier for frequency modulation FM and digital modulation. This ist he reason why it should work in the linear range.

An amplifier module is used, which fulfils the demanded characteristics in the best pos-sible way. The component RA 13H4047M is in the best way suitable for this application. A further important criterion is the no-load operation and short-circuit security. The boost of the amplifier should be variable. The power adjustment takes place by means of an ad-justable attenuator, which is switched before the amplifier. The attenuator is controlled via interface to a computer.

The result is a fully functional amplifier, which can be used in the taxi-radio range.