In this paper, a low-power structure as an inverter-base circuit is reported for broadband applications. The focus in this study is in obtaining a low-power structure. By applying cascoded structure to an inverter as a feedforward network in the structure, the DC current and hence the power dissipation are decreased. Also, by adding a two-stage active feedback, which yields no miller capacitance, to the cascoded inverter, the structure of the TIA is completed. Simulation results in HSPICE using 90[Formula: see text]nm CMOS technology parameters show 41[Formula: see text]dB[Formula: see text] transimpedance gain, 6.5[Formula: see text]GHz frequency bandwidth and 2.7[Formula: see text][Formula: see text]Arms input referred noise, which consumes only 1.67[Formula: see text]mw power at 1[Formula: see text]V supply. Results and analysis indicate that the proposed TIA is suitable to work as a low-power 10 Gbps transimpedance amplifier in an optical receiver.

This article discusses a multi-stage transimpedance amplifier (TIA), which is based on three stages of a modified inverter structure. The traditional inverter structures’ performances are improved adding two cascoded transistors. This new structure benefits from elimination of the Miller-capacitances in comparison with the traditional inverters, which can provide higher speed and wider frequency bandwidth. Manipulating the trade-offs among bandwidth, gain and power consumption beside using Gm/ID technique, this paper introduces a low-power transimpedance amplifier for high-bit rates in optical communication receiver systems. Moreover, active types of inductors are also used to lesson the occupied area and increase the frequency bandwidth. Transferring poles of the improved circuit to higher frequencies means less required DC current for a fixed bandwidth range, which results in low-power characteristic.

In this paper, we propose a new scheme for data embedding in color video. Traditionally for data embedding in color images, the blue component is modified based on embedded data. This method fails when the picture has very low density of pixel with strong blue component. We devise an adaptive embedding scheme in which the data are embedded in blue or red component of some pixels in each video frames based on their density. This scheme requires no knowledge of the original video for the recovery of the embedded data. We experiment the proposed scheme for embedding an average of 30 bits per frame in the spatial domain of a color host video with QCIF format. Simulation results show that this data embedding scheme low visible distortions in the host video.

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An optical communication receiver system is presented in this research using 65nm CMOS, which consists of three lowpower active differential stages as Limiting Amplifier (LA) following an ultra-low-power RGC-Based Transimpedance Amplifier (RB-TIA). The presented active circuit of the RB-TIA is followed by a gain stage that extends the-3dB frequency of the circuit by creating a resonance for the load capacitance. Thus, needless of consuming extra power, a wide-bandwidth circuit has been designed. In addition, employing active-inductor loads within the LA stages enables obtaining a 5Gbps receiver system. The RB-TIA consumes 573µW and provides 3.52GHz frequency, while the complete optical receiver consumes only 4.76mW power to provide-3dB frequency of 3.5GHz and high gain of 80dB (10'000). The circuits have been mathematically presented and discussed, and simulations have justified the presented circuit design.