Wideband Inductor-less LNA with Resistive Feedback and Noise Cancelation

Abstract: In this master thesis a wideband, inductorless LNA for GSM andWCDMA with noise canceling is examined and designed in 90-nm RFCMOS process. The goal was to design a wideband LNA that couldwork as a drop in solution in ST-Ericsson’s receiver and have an inputmatch below -12 dB for a bandwidth of 800 MHz to 2.5 GHz. Theproposed LNA combines two techniques, resistive feedback and noisecancellation to provide both a wideband input match and good noiseand linearity performance.
The result is a wideband, differential LNA without any need for externalmatching components. Furthermore, the solution is inductorlesswhich saves valuable area on chip. The LNA covers frequency bandswithin 800 MHz – 2.5 GHz with S11 below -12.8 dBm and providesa voltage gain of 27 dB. The NF is below 2.1 dB and IIP3 is greaterthan -4 dBm with a power consumption of only 28 mW. In the receivertest bench the mixer is used as load which results in a conversion gainhigher than 24 dB, S11 below -12.8 dBm, NF below 4 dB and IIP3higher than -6.2 dB.
This solution has many features such as high bandwidth with agood input match, inductorless design saving area and costs and isfully differential.