Pulse Modulation

Abstract-We present a steady-state analysis of high-repetition-rate passively mode-locked semiconductor lasers. The analysis includes effects of amplitude-to-phase coupling in both gain and absorber sections. A many-mode eigenvalue approach is pre-sented to obtain supermode ...

IT IS NOW widely recognized that the Integrated Services Digital Network (ISDN) concept is providing a useful framework for the development of future telecommunications networks and services. An ISDN can be regarded as a generalpurpose digital network capable of supporting (or integrating) a wide range of services (voice and non-voice) using a small set of standard multipurpose user-network interfaces. Relevant CCITT Recommendations (or standards) on ISDN interfaces were expected to be available in 1984, the final year of the current study period. This paper reviews CCITT progress on the architectural studies of protocols associated with ISDN's, in particular, the ISDN Protocol Reference Model being developed by Study Group XVIII. This Model, based on the concepts and principles of the ISO/CCITT Open Systems Interconnection (OSI) Reference Model, aims at providing a unified framework for modeling ISDN multiservice communications and capabilities. The new Model is applied to several possible ISDN communications configurations, enabling a number of technical issues to be easily identified.

Pulse compression theory and techniques were developed originally for radar systems but could be carefully adopted for ultrasound-specific problems. In past ten years a considerable amount of research has been done in the area of mismatched filtering for the purpose of its application in ultrasound. However, in a similar way to radar systems for distributed targets, pulse compression has not achieved a success of penetration in commercially available systems.

This paper presents the design and analysis of a new configuration of parallel connected inverter suitable for Distributed Generation Application. The configuration consists of dc/dc converter and parallel three-phase dc/ac inverter. Series resistors added to the inverter output to maintain same current in each inverter of the two parallel inverters, and to reduce the circulating current in the parallel inverters to the minimum. Third harmonic injection PWM (THIPWM) reduces the total harmonic distortion and to make maximum use of the voltage source. DSP was used to generate the THIPWM and the control algorithm for the converter. PID controller is applied on the full-bridge dc/dc converter side to maintain the ac voltage to the required level. Selected experimental results have been shown to validate the proposed system.

http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=5138746

This paper presents the design and analysis of a new configuration of parallel connected inverter suitable for fuel cell system application. The configuration consists of dc/dc converter and parallel three-phase dc/ac inverter. Series resistors added to the inverter output to maintain same current in each inverter of the two parallel inverters, and to reduce the circulating current in the parallel inverters to minimum. Third harmonic injection PWM (THIPWM) reduces the total harmonic distortion and to make maximum use of the voltage source. DSP was used to create the THIPWM and the control algorithm for the converter. PID controller is applied on the full-bridge dc/dc converter side to maintain the ac voltage to the required level. Experimental results have been shown to validate the proposed system.

This paper describes the integration in a CMOS 130 nm technology of an ultra wide band (UWB) pulse generator. The implemented generator controls the output pulse shape, and thus the corresponding spectrum. Furthermore, the pulse generator supports both position modulation (2-PPM) and polarity modulation (BPSK) and draws 5 mA from 1.2 V. Spectral and temporal laboratory measurements of the single-chip pulse generator are presented.

In this work, we have successfully developed a stand-alone system for positioning both static and dynamic targets in an indoor environment with approximately 2 mm and 6 mm of 3-D accuracy, respectively. The results are considered a great milestone in developing such technology. 1D and 3D experiments have been carried out and validated using an optical reference system which provides better than 0.3 mm 3D accuracy. Such a high accuracy wireless localization system should have a great impact on many applications that require such high positioning precision.