A 0.6–5.5GHz E-PHEMT broadband high-gain LNA designed by ADS

An ultra-wide band(UWB) low noise amplifier (LNA) of bandwidth 0.6–5.5GHz, gain more than 27dB, flatness fluctuating in ±2dB, noise-figure less than 1.2dB and the input and output reflection coefficient is less than −10dB within the range of the bandwidth is designed and simulated. This LNA utilizes both series negative-feedback in the source electrode and parallel negative-feedback between the drain electrode and the gate electrode to compensate the decrease of the high frequency gain. Comparing with traditional inductance negative-feedback between the drain electrode and the gate electrode, this adding resistance series capacitance feedback can improve gain-flatness and expand bandwidth obviously. Furthermore, this design adopt two stage cascade technology to achieve high gain and a transmission line of TL29 is used to achieve broadband match of an input and output port. Simulated in schematic and layout results are in excellent agreement.