6-2 Digital Transmission Systems

frame alignment procedure in digital transmission systems

every digital transmission system requires frame alignment. it is necessary to identify the varius signal componets and to bring receiver into phase with respect to the transmission format so that the digits can be properly assembled for demultiplexing. fast and reliable frame alignmant is important, and therefore has been a subject for study. this paper a comprehensive analysis of frame alignm...

Vectored transmission for digital subscriber line systems

This paper describes the “vectored” transmission technique for digital subscriber line (DSL) systems, which utilizes user coordination at the central office or optical network unit. This method exploits the colocation of the downstream transmitters and of the upstream receivers, in order to achieve far-end crosstalk (FEXT) cancellation and perform multiuser transmission optimization. The perfor...

Quadrature Amplitude Modulated Digital Radio Transmission Modeling and Simulation

Computer aided design and computer aided modeling tools are becoming increasingly important in the design and performance evaluation of communication systems. In this work, we report on the computer simulation modeling study of terrestrial digital microwave radio transmission, using Block Oriented System Simulator package (BOSS). The work concentrates on semi-analytical error rate evaluation in...

Transmission Rate Enhancement Schemes for Digital Radio Mondiale Systems

In this paper, transmission rate enhancement schemes for DRM (Digital Radio Mondiale), which is a worldwide standard for digital AM and FM broadcasting in the AM and FM bands below 170 MHz, are presented and compared. The data rate of the legacy DRM system is supported up-to 186kbps with 16QAM and MLC (Multi-level Coding) at 100 kHz bandwidth. However, this rate is not sufficient to achieve new...

Standardization Sector of Itu General Aspects of Digital Transmission Systems