Calculation Methods for Noise Quantities

For noise variables, the RMS value is obtained by integrating the spectral power density, the one‐sided spectral power density over the frequency. In linear circuit analyses, voltages and currents are interrelated using suitable matrices. This chapter introduces the noise waves and explains their relationship with the noise currents in the admittance representation. The goal of noise analysis of a communication system is to calculate the level of fluctuations in a receiver. The consideration carried out is only useful for simple special cases and should show the principles of noise modeling. The noise correlation matrices are available in a suitable form for each network description, as are the different networks used in signal analysis. The chapter discusses an example that is very similar to a field effect transistor (FET), but contains only a minimum of elements. It corresponds to the approach for the intrinsic part of an FET chip in the Pospieszalski model.