Dual-Input Pseudo-Switch RF Low Noise Amplifier

A dual-input low noise amplifier (DILNA) topology with pseudo-switch capability is presented. This novel solution allows us to avoid the use of the RF switch in all cases in which the LNA input has to be switched alternatively between two different RF sources. This is obtained by duplicating the input stage of the LNA and creating two concurrent stages. In the particular case of 13-GHz radiometric applications, the DILNA circuit has been realized in 90-nm CMOS technology, and the measurement results have shown a noise figure of 2.5 dB, a power gain close to 19 dB from both inputs, an input-output isolation close to -60 dB, and an isolation between the two inputs of about -45 dB at 13 GHz. The power consumption amounts to 17.38 mW from a 1.1-V supply voltage. These results represent one of the best sets of performance among those presented in the literature.