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D
Published in Philip A. Laplante, Comprehensive Dictionary of Electrical Engineering, 2018
distributed amplifier composed of two main artificial transmission-line sections consisting of series inductors and shunt capacitors, which are usually supplied by the FET transistor. Excellent bandwidth performers are obtainable and the amplifier can be designed as wideband low-noise amplifiers and are relatively easy to simulate and fabricate. distributed amplifier the input and output capacitance of the active devices can be absorbed into distributed circuits (i.e., transmission lines) to obtain a very broad bandwidth. distributed antenna typically consists of a set of discrete radiators fed by a common cable from a single signal source.
Group Iii-Nitride Microwave Monolithically Integrated Circuits
Published in Farid Medjdoub, Krzysztof Iniewski, Gallium Nitride (GaN), 2017
Distributed amplifier can provide more than an octave bandwidth. High-efficiency GaN PA using a non-uniform distributed (NDPA) topology is proposed by Gassmann et al. [114]. The NDPA topology is useful, as it improves the matching conditions of various FETs. A comparison of GaN to MMIC amplifiers in GaAs technology is given by Meharry et al. [115]. The GaAs amplifiers are found to be more complex, whereas the ration of the GaAs to the GaN gate periphery is about 14.4 mm to 2 mm, that is, an improvement for GaN of 7:1.
Power Amplifier Circuit
Published in Mike Golio, Commercial Wireless Circuits and Components Handbook, 2018
The distributed amplifier concept uses the parasitic capacitance/inductance of a transistor as part of two artificial transmission lines. The transmission lines are a lumped equivalent of a distributed line, with some of the lumped elements formed in the transistor. Hence, as the amplifier appears to be a transmission line, it is matched into the required terminations over a very wide bandwidth. That is the benefit of this topology — bandwidths up to many octaves are possible.
Kronecker Product Based Modeling of Darlington Amplifier and State Estimation using Unscented Kalman Filter
Published in International Journal of Electronics Letters, 2022
Amit Kumar Gautam, Sudipta Majumdar
Darlington amplifier has been used in various applications including broadband high-data-rate communication systems. The three-stage Darlington feedback amplifier presents better stability than single-stage Darlington feedback amplifier. DA circuit has been used in various broadband circuits. In addition, it has high-speed applications. Besides these, it is also used in low-noise amplifier (Lee & Cressler, 2006), mixer (Tsai etal., 2005), power amplifier (PA)(Kuo etal., 2013), distributed amplifier and active baluns (Weng etal., 2009). The DA is also used as a benchmark for verification of compact models at millimeter-wave frequencies (Mukherjee et al., 2016). Shukla and Pandey (2014) used DA together with Sziklai to model two-stage small-signal amplifier. Mojab and Mazumder (2016) proposed an optical Darlington transistor for high-power applications. Weng etal. (2012) proposed broadband DA using heterojunction bipolar transistor for high-speed data communications. Various designs have been proposed for DA. Lee and Cressler (2005) proposed the design of ultra-wideband DA. Weng etal. (2010) proposed a design of DA for microwave broadband applications. Darlington pair topology is also used in medium PA for wireless and wireline data technology (Z. He etal., 2020). To obtain the large bandwidth and watt-level power output for satellite communication, Darlington power stage is used in two stages (Cai etal., 2020). It is also used in GaN HEMT Darlington PA for high efficiency, large dynamic range and low distortion characteristics (Kitamura etal., 2018).
A universal current-mode current conveyor filter based on GFET inverter
Published in International Journal of Electronics Letters, 2022
In recent years, several graphene FET circuits have been presented, including ring oscillator (Bianchi et al., 2015, April; Guerriero et al., 2013, May; Safari & Dousti, 2020, March), phase shifter (Medina-Rull et al., 2020, November), operational amplifier (Safari et al., 2018, June), distributed amplifier (Safari et al., 2019, February), voltage amplifiers (Han et al., 2011, August; Yang et al., 2010, October), power amplifiers (Hanna et al., 2017, January), mixers (Habibpour et al., 2011, January; Y. M. Lin et al., 2011, June; Wang et al. 2010, October), frequency multipliers (Ramon et al., 2012, September; Wang et al., 2009, May; Wang et al., 2010, May) and photodetectors and optical modulators (Sorianello, 2021, April).