Patent ID: 6140858
Filing Date: 2000-10-31
Classification: H03F,H04B

Abstract:
A predistortion circuit of an electric signal, comprisinga branch called primary branch connecting an input to an output,a delay circuit for delaying the signal in the primary branch,a coupler/shunting device which samples a fraction of the input signal,a branch called secondary branch connected to the shunting output of the coupler/shunting device, comprising a second-harmonic generator,a coupler/shunting device which receives the output signal of the secondary branch and adds this signal to the signal on the output of the primary branch, characterized in that the second-harmonic generator is formed bya divider/phase shifter producing two anti-phase signals on two first connections,two pairs of cascaded diodes, each of them being connected between the two first connections, the diodes of the first pair being interconnected by their cathodes and those of tile other pair being interconnected by their anodes,means for biasing the four diodes in forward direction,two second connections connected respectively to the node of the two cathodes and to the node of the two anodes, which form a symmetrical output.