Showing 2 results for Bijari
Dr. Abolfazl Bijari, Mahdi Sheikhi,
Volume 16, Issue 2 (JIAEEE Vol.16 No.2 2019)
Abstract
This paper presents a new variable gain low noise amplifier (VG-LNA) for ultra-wideband (UWB) applications. The proposed VG-LNA uses a common-source (CS) with a shunt-shunt active feedback as an input stage to realize input matching and partial noise cancelling. An output stage consists of a gain-boosted CS cascode and a gain control circuit that moves the high resonant frequency to higher frequencies and provides flatness gain. The direct power gain (S21) is continuously controlled without significant degradation in the input return loss (S11) and noise figure. The proposed VG-LNA is designed and simulated using RF-TSMC 0.18 μm CMOS technology by Advanced Design System (ADS). Simulation results show a maximum flat power gain (S21) of 14 dB with a noise figure (NF) lower than 3.6 dB and an input impedance matching (S11) less than –10 dB over the wide bandwidth of 3.5 to 13.5 GHz. Its power consumption is 12 mW with low power supply of 0.9 V. In addition, the power gain ranges from 7 to 14 dB at the center frequency of 8.5 GHz.
Dr. Abolfazl Bijari, Somayeh Abbasi Avval, ,
Volume 19, Issue 3 (JIAEEE Vol.19 No.3 2022)
Abstract
In this paper, a low power 2×3 matrix distributed amplifier (DA) with tapper transmission lines is introduced in 180 nm CMOS technology. The matrix structure is used to provide the mechanisms of multiplication and additive of the current for increasing the gain and reducing the power consumption. In the input stage, a controllable cascade gain cell is used to expand the bandwidth and remove to need the additional capacitors in the input gate and central transmission lines. Moreover, the terminating resistor of the input gate transmission line is replaced with an RL network. The proposed distributed amplifier is designed and simulated using TSMC 0.18 µm CMOS technology in Cadence Spectre-RF over the frequency of 1-30 GHz. Operated at 1 V, the proposed DA consumes 25.16 mW. Simulation results show that the proposed DA achieves a direct power gain (S21) of 12±1 dB with an average NF of 5.75 dB and average IIP3 of -6.11 over the 1–24 GHz band of interest. The input and output return losses are also more than 10 dB.
