Patent ID: 8547176

Claim:
A distributed power amplifier arranged to operate over a bandwidth, the distributed power amplifier comprising: an input side comprising an input terminal arranged to receive an input signal and connected to an input transmission line, an output side comprising an output terminal adapted to deliver an output signal and connected to an output transmission line, the input signal being arranged to be successively coupled from the input transmission line to the output transmission line through amplifiers connected between the input transmission line and the output transmission line, both transmission lines having two ends, a power splitter connected to the input terminal, thus being arranged to divide the input signal in a first path to the input transmission line and in a second path to an input of an active matching circuit, the active matching circuit having an output connected to the output transmission line, the other end of the output transmission line being connected to the output terminal, thus achieving an improved power added efficiency performance and increased power output over the bandwidth, wherein the input transmission line comprises m transmission line sections L in connected in series, where n is an integer ranging from 1 to m, the output terminal, located at the output side of the distributed power amplifier, is connected to an output end of the output transmission line, the output transmission line comprising m transmission line sections L on connected in series, where n is an integer ranging from 1 to m, amplifiers A 1 to A m−1 each with an input-terminal, an output-terminal and a ground-terminal, are connected to the input transmission line and the output transmission line, with the input terminal being connected to the input transmission line and the output terminal to the output transmission line, each ground terminal being connected to ground, there is one amplifier connection from a point between each pair of transmission line sections L ip /L ip+1 on the input transmission line to a point between each pair of transmission line sections L op /L op+1 on the output transmission line where p is an integer ranging from 1 to m−1, the output of the active matching circuit is connected to an opposite end of the output transmission line, and the active matching circuit comprises: at least one amplifier arranged to produce a boost to the output signal and a matching arrangement adapted to adjust output impedance of the distributed power amplifier over the bandwidth.