الفهرس 
Chapter 1 Introduction and MotivationOnly 14 pages are availabe for public view
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Abstract
Optical communications have revolutionized modern telecommuni-cations, enabling the rapid and efficient transmission of vast amounts of data over long distances. By using light waves as carriers for infor-mation, optical communication systems offer unparalleled data rates, low latency, and immunity to electromagnetic interference. The tran-simpedance amplifier (TIA) plays a crucial role in determining the overall performance of the optical receiver. Parameters such as gain, bandwidth, noise figure, and linearity are influenced significantly by the design of the TIA. Optimizing these parameters meets the ever-growing demands of modern applications.
This thesis comprises three main parts. Firstly, an investigation of two widely used transimpedance-amplifier configurations is presented. The two adopted configurations are the regulated cascode-based TIA (RGC-TIA) and the common-source based TIA (CS-TIA). These two configurations are studied in the three inversion regimes; weak, mod-erate, and strong inversion levels. A general model for the drain current of the MOSFET transistor that is valid in all levels of inversion is adopted. This work involves a systematic study of the two adopted configurations through varying the inversion coefficient (IC) and stud-ying the effect of varying the IC on various performance metrics such as the gain, bandwidth, input-referred noise current, area, total har-monic distortion, and power consumption. This study is performed by simulation adopting the 130-nm CMOS technology with a power-supply voltage, VDD, equal to 1.2 V.
Secondly, four TIA topologies, including the RGC, CS, CMOS in-verter, and composite cascode, are compared and evaluated in gate-driven (GD) and body-driven (BD) configurations, addressing diverse application requirements. The composite cascode topology is intro-duced for the first time in TIAs. The simulation is performed utilizing 130-nm CMOS technology PTM with a power-supply voltage, VDD, of 1.2 V for GD configurations and 0.9 V for BD configurations.
Finally, a novel current-mirror based CMOS TIA is introduced and designed to be suitable for optical communications. The operation of the proposed TIA is verified by suitable analytical and simulation re-sults. The simulation employs the 45-nm CMOS technology with a power-supply voltage of 1 V. The simulation results reveal several trade-offs between the various performance metrics. The simulation throughout the thesis is performed by Multisim.