Highly Linear Low Noise Amplifier for 2.45 GHz

The quality of a communication system is mainly influenced by the sensitivity of the receiver. A critical receiver stage is the first amplifier [low noise amplifier (LNA)] that should have a low noise figure (NF) as well as sufficient gain to provide high sensitivity and also a high dynamic range to avoid intermodulation products from strong signals. The third-order intermodulation products have substantial influence on the receiver performance. These undesired signals appear in a band close to the operating frequency and cause interference in the receiver system. In most cases intermodulation can be reduced by increasing the current through the active device [transistor, field effect transistor (FET), etc.], however with mobile terminals, the power consumption is an essential factor and therefore a tradeoff is required. The objective of the LNA Student Design Contest at the 2011 IEEE International Microwave Symposium (IMS2011) in Baltimore was to construct an LNA that also takes into account the linearity and a the overall power consumption.