Design of narrowband and wideband low noise amplifier for RADAR applications

Abstract

This thesis reviews and analyze the designing of Low Noise Amplifier (LNA) inX-band. X-band frequencies are mostly used in RADAR receivers. The transistorused for design is GaAs FET because of its better performance at high frequenciescompared to other FETs. Two-stage common source configuration is designed inNarrow-band LNA to achieve low noise figure, better gain and low power consumption.21.2 dB gain is achieved at frequency 8.4 GHz with noise figure of 0.5dB, which is better compared to the other work done using MOSFET. LNA is biasedat 2 V and 15 mA. In the second part, two Wide-band LNA topologies aredesigned for different applications. Feedback technique is used to achieve flatgain and low noise figure. First one is in 6 to 7 GHz band, that achieves gain of17.8 0.5 dB and noise figure 0.1 0.03 dB. This design topology has very lownoise figure but gain is compromised. The other design is in the band 6 to 10GHz. 21.3 dB gain is achieved across the band 6 to 10 GHz with variation of 0.5dB. Noise figure is 1.1 0.3 dB over the characterized bandwidth. This designtopology has better gain and bandwidth compared to the previous one, but it hasmore noise figure. So both designs have their own advantages and disadvantages.RADAR receivers has many applications, such as communication, defense,remote sensing, etc.