Design and Performance of a 3.4 to 4.6 GHz Active Equalizer with Controlled Gain Slope

We present the design and performance of a low-noise tuneable active equalizer (AEQ) intended to compensate frequency dependent losses in the coaxial cable. The equalizer achieves 11 dB gain with a typical noise figure of 2.2 dB and has a slope of 3.5 dB within the 3.4-4.6 GHz band. The possibility to tune the AEQ gain-slope and hence obtain accurate flatness inside the pass-band is provided by two PIN diodes as voltage controlled resistors. The slope can be varied by +/- 0.7 dB without disturbing slope-linearity.