TunableQ-enhanced LC dual-band filtering at microwave frequencies in 0.13 µm SiGe BiCMOS

Abstract

AbstractThis paper presents an activeQ-enhanced LC dual-band band-pass filtering approach using parallel synthesis techniques at X- and Ku-bands in 0.13µm SiGe BiCMOS technology. By employing two independently tunable parallel LC-tanks with either in-phase and out-of-phase addition, independently tunable dual-band filtering is achieved. For higher out-of-band (OOB) attenuation, subtraction of the two 2nd-order bandpass filter is implemented. The two bands are independently tunable in terms ofQand center frequency. The dual-band filter at 9.7 GHz and 13.9 GHz achieves a normalized dynamic range of 165–154.5 dB.Hz with an OOB attenuation of >50 dB below 3 GHz. In between the two bands, the attenuation is 22 dB when the two passbands have 200 MHz bandwidth each. The total group delay is 0.8 ns and 1.9 ns forQof 20 and 50, respectively. The filter achieves better OOB rejection with wider band channels at X- and Ku-bands compared with state of the art integrated filters. The filter consumes 115–130 mW of DC power. The core die area is 0.53 × 0.7 mm2.