Abstract We proposed a compact 1 × multimode interference (MMI) optical modulator with high extinction ratio. A triply coupled quantum well structure is designed for the core layer enhancement of quantum-confined Stark effect, and MMI waveguide isolation trenches symmetrically designed. The length reduced by 30%, wavelength dependence was compared that observed in previously reported modulator....

We present a globally stable arbitrary-order single-bit delta-sigma modulator architecture with continuous-time loop filtering. Using Lyapunov arguments and the method of equivalent control, it is shown that stability is guaranteed for any input signal with peak magnitude less than L > 0, where L and +L denote the quantization levels. The design augments the conventional deltasigma modulator wi...

In this paper, for the rst time, a high performance hybrid silicon evanescent traveling wave electroabsorption modulator based on asymmetric intra-step-barrier coupled double strained quantum wells active layer is introduced which has double steps at III/V mesa structure. Through this active layer, hybrid silicon evanescent traveling wave electroabsorption modulator will be advantages such as v...

This paper describes an implementation of a bandpass sigma-delta modulator behavioral model with SIMPLORER VHDL-AMS. The model includes most of the non-idealities which affect the performance of the component, such as sampling jitter, kT/C noise and operational amplifier parameters. A comparison with another model, implemented with MATLABSIMULINK by Brigati et al., is made to highlight and val...

An analysis is presented for the transfer functions of a particular pulse-width modulator and power switch subsystem that has been widely used in practical switching-mode d-c regulator systems. The switch and filter are in a "buck" configuration, and the switch is driven by a con­ stant-frequency variable duty-ratio push-pull magnetic modulator employing square-loop cores. The two transfer func...

An all solid-state kicker modulator for the Dual-Axis Radiographic Hydrodynamic Test facility (DARHT-2) has been designed and tested. This kicker modulator uses multiple solid-state modules stacked in an inductive-adder configuration where the energy is switched into each section of the adder by a parallel array of MOSFETs. The modulator features very fast rise and fall times, pulse width agili...

In this paper, a 60 GHz LTCC SiP with low-power CMOS OOK modulator and demodulator is presented. The 60 GHz modulator is designed in a 90-nm CMOS process. The modulator uses a current reuse technique and only consumes 14.4-mW of DC power in the on-state. The measured data rate is up to 2 Gb/s. The 60 GHz OOK demodulator is designed in a 130nm CMOS process. The demodulator consists of a gain boo...

This paper describes the design and implementation of a low power reconfigurable sigma-delta modulator for multi-standard wireless applications in a 90-nm CMOS technology. Both architectural and circuital reconfigurations are used to adapt the performance of the modulator to five different communication standards. The feasibility of the proposed solution is shown using the system-level simulati...

A novel structure of VCO-based quantizer for CT ΣΔ modulator is presented which can significantly improve the VCO linearity. Compared to the traditional methods, the proposed structure uses only one VCO in the system and it also maintains the intrinsic Dynamic Element Matching (DEM) function of the VCO-based quantizer. A first order CT ΣΔ modulator with the proposed quantizer is designed and si...

A drawback of continuous time Σ∆-modulators is their sensitivity to clock jitter. An appropriate way to counteract this is to use a multi bit feedback loop. This requires a high resolution multi bit quantizer. However, every extra bit in the quantizer doubles its complexity and power consumption. In this paper, a new Σ∆-modulator architecture is proposed. The implementation issues are discussed...