Wideband, high gain, high linearity, low noise amplifier for GNSS frequencies with compensation for low frequency instability

This paper presents the design methodology, simulation results and implementation details of a low noise amplifier (LNA) designed to operate over the whole range of Global Navigation Satellite System (GNSS) frequencies (1164 MHz to 1615.5 MHz). This LNA works over combined (but overlapping) frequency bands of all three GNSS constellations (GNSS consist of the American Global Positioning System (GPS), European Galileo system and the Russian GLONASS system). Designed to be unconditionally stable with gain of over 18 dB and noise figure of 2 dB over a considerable bandwidth of about 450 MHz, the achieved results conformed quite well to the specifications. Final implementation results include a gain of 18.5 dB at the centre frequency with a nominal variation of ±1.3 dB over the desired bandwidth. The noise figure obtained is 2.18 dB and the amplifier stability range extends from 0 Hz to 9 GHz. Very high degree of linearity is achieved with output ldB compression at +13 dBm and output third order intercept at +23 dBm. This paper describes results at every stage of design, simulation and implementation along with a solution against typical low frequency instability by a small trade-off in noise figure.