Microwave Selective Amplifiers with High Asymptotic Attenuation in the Range of Subresonance Frequencies

The paper considers the advanced principle of construction of high quality low-bandwidth CMOS selective amplifiers (SAs) with low sensitiveness to unsettling influences of HF and microwave ranges. The suggested solutions provide cascading of several SAs without decoupling capacitors and additional DC level shifters. The considered SAs are characterized by the opportunity to choose the resistances of the circuit which specifies frequency in a wide range of rating values. In contrast with the well-known ones the proposed architecture of SA reduces the signals attenuation not only in the traditional high-frequency range but also in the low-frequency one (up to-70 dB) without additional decoupling capacitors. The paper presents the results of mathematical analysis and computer simulation of SA on the components of SiGe technological process SG25H1.