Analysis of cascaded diplexer amplifier for 2.4GHz/5GHz of WLAN’s transmitter

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Vorapong Silaphan
Ittipat Rubkom


This article presents an analysis of the cascaded diplexer amplifier circuit dual passband frequencies for WLAN 2.4 GHz / 5GHz. By adjusting input impedance matching circuits, series resonance, parallel resonance and gate capacitance of the active device for resonance inductor and capacitors. The simulation results show that the circuit gain is 20dB and 19.4dB, with FBW values of 20.8% and 16.4% at 2.4GHz and 5GHz, respectively. These results are good agreement with the theoretical analysis.

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