| Recently, with the development of the satellite navigation, the investigations on the compact and high performances microwave components are the focus of the research. The low noise amplifier (LNA), which is the front end of the satellite navigation receive, its compact structure and high performances will affect the performances of receive. In this thesis, three LNAs are designed and fabricated according to the requirements of the satellite navigation.The main content of this thesis can be summarized as follows:First is a two-stage-transistor LNA. This amplifier uses ATF-54143transistor produced by AVAGO company. And this LNA is matched in two ways:the lumped parameter element matching and distributed parameter matching. From the measured results, the working bandwidth is500MHz, the noise figure is1.2dB and the gain is30dB are achieved at35mmX35mm compact size.Second is a two-stage-chip LNA. This amplifier uses MAX2569produced by Maxim. From the measured results, this LNA is working at1.558GHz-1.579GHz.The noise figure is1.2dB and the gain is28dB. The out-of-band rejection is above35dB. The size of the amplifier is limited at15mmX15mm.Third is a three-stage-LNA.. This amplifier is working at1.2GHz-1.7GHz. The noise figure is2dB and the gain is28dB and40dB. To avoid the interferences of the navigation signals, the filter has been used to separate the working bandwidth. From the measured results, has demands of wide-band, low-noise, low-standing wave and high-gain at the same time, so balanced amplifier is needed to be designed. The amplifier has two bandwidths, and both have out-band suppression above35dB. The size of the amplifier is limited. It turned out that all of its noise coefficient, standing wave, gain, flatness and external inhibition meeted the requirements. |
