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An improvement in linearity of LNA amplifiers is achieved in proposed paper using auxiliary path, paralleled with the main amplifier. Moreover a cascode structure is employed to reach better amplifier parameter. Phase and amplitude are set through the second path and additional inductances in this transistor Source. Consequently non-linearity coefficient is controlled which leads to minimize the overall non-linearity coefficient. An investigation is also conducted on second-order non linearity coefficient which directly influences on IIP3. Power analyses can be used for it buta volterra analysis is applied for more accuracy and better nonlinearity modeling. DS method which is proposed in this paper can be added to various amplifier circuits since it parallels with the main circuit. Noise figure is controlled since the gates of transistors are not connected together directly. In this case we have reached an appropriate linearity which was anticipated the simulation results show a gain of 18dB, a noise figure of 2. 43dB, and an IIP3 of 7. 5dBm. All simulations are carried out using in 0. 18 µ m TSMC-RF technology.

The Low Noise Amplifier (LNA) stands as a crucial element RF receiver chain, demanding a delicate interplay of characteristics such as high gain, low noise figure (NF), superior linearity, and an extensive dynamic range. De-signing an ultrawideband (UWB) LNA poses a complex challenge as engineers grapple with intricate trade-offs inherent in these parameters. To address these challenges, noise cancellation techniques have emerged as valuable tools, revolutionizing the design of UWB LNAs by relaxing the traditional trade-off between bandwidth and input matching. This innovative approach not only enhances bandwidth but also effectively cancels out the un-desirable noise and nonlinearities from the input MOSFET. Despite the advancements afforded by noise cancellation, the broad bandwidth of UWB LNAs presents a significant hurdle. If the linearity is insufficient, the UWB LNA faces performance degradation due to increase in-band interference. In response, this article proposes an inventive linearization technique, a combination of Noise Cancelling (NC) and complementary derivative super-position (CDS), aiming to increase the linearity of UWB LNAs. Through meticulous simulations conducted using Cadence Virtuoso with GPDK090 library, the proposed LNA showcases impressive performance metrics across the UWB spectrum. Notably, it achieves a gain ranging from 12.5 dB to 15.5 dB, a noise figure within the range of 3.9 dB to 5.26 dB, and an IIP3 spanning from 6.3 dBm to 8.8 dBm. Remarkably, this innovative LNA accomplishes these feats while operating with a modest power consumption of 11.36 mW from a 1.2 V supply. This groundbreaking technique holds promise for significantly enhancing the efficiency and overall performance of UWB LNAs within contemporary RF receiver systems.

In this paper, an optimum distribution of gate delays for the control unit (CU), forming the control signals for the charge pump (CP) of the phase-frequency detector (PFD), is investigated. It is shown that at selection of delays the dynamic parameters of the CP must be also taken into account to ensure linear transfer characteristic (TC) of the PFD. Some critical aspects (substantial non-linearity of the TC, the dead zone phenomenon, and parasitic oscillation) are considered.

In this paper, a new approach for improving the linearity characteristics of GaN power amplifiers is presented. The method is based on the injection of the second harmonic signal to the input of the power amplifier through a forward path. The effect of the second harmonic injection on the linearity characteristics of the power amplifier is studied using two-tone theory and simulations. An active three-port linearizing circuit with the ability to generate a second harmonic signal with adjustable amplitude and phase has been proposed to implement this method. Further, the paper method has been evaluated for improving the linearity of two 10-watt power amplifiers with different nonlinear characteristics. As a concept, the proposed circuit is also fabricated and used for linearizing the GaN power amplifier. It has been shown that by injecting the second harmonic signal and properly adjusting its amplitude and phase, in addition to improving the linearity characteristics, including third-order intermodulation (IMD3), adjacent channel power ratio (ACPR), and AM-PM characteristic, the 1-dB compression point is also increased.

In the new advanced drive schemes, identification and modeling of the load complex characteristics can play an important role to predict the dynamic performance of the proposed control strategy. The novelty of this paper consists in the classification of the different types of the nonlinear loads which the electrical drive systems may encounter. In this study, nonlinear components of mechanical loads are divided into two groups. The first type includes nonlinear phenomenon caused by the nature of load which is predictable and identifiable. Another type of loads nonlinear characteristic happens due to the occurrence of a mechanical fault in motor, coupling or load parts. Generally, this type of non-intended nonlinear effect is not predictable and often occurs in the installation and operation stage of the drive system utilization. In this paper, the performance of an induction servo drive system has been simulated under the influence of different types of non-linear industrial loads.