Broadband Matching of a Complex Load, Applied to a Reflection Amplifier using an IMPATT-Diode.

An improved approach to broadband matching of a complex load, given only by measured impedance data is presented. Neither the topology nor the system transfer function of the lossless equalizer are initially assumed. The network results from a numerical design procedure. The procedure is based on the Bode relations between the real and imaginary parts of analytical functions. The real part of the impedance, seen from the load side into the equalizer is modified until the gain response becomes optimal. This approach was introduced by Carlin. His method for calculating the imaginary from the real part has been abandoned in favour of a faster procedure. To synthesize the equalizer network, the best possible real part characteristic is then approximated by an even, rational function. This approximation is found by a new, fast algorithm, yielding good solutions with only a few interactive steps. The practical workability of the procedure was checked by designing three reflection amplifier networks and proved by measuring the performance of one of those amplifiers, which has been realized in microstrip technique.