METHOD TO TRANSFER DATA
申请公布号:IL141174(D0)
申请号:IL20010141174
申请日期:2001.01.30
申请公布日期:2002.02.10
分类号:H04L27/34;H04L1/00;H04L12/56;H04L27/00;H04L27/26;H04M11/06;(IPC1-7):H04L
主分类号:H04L27/34
摘要:A method to transfer data from a digital data modulator device (MOD) to a digital data demodulator device (DMOD) over a digital subscriber line (TL) according to the ADSL ÄAsymmetric Digital Subscriber LineÜ or the VDSL ÄVery High Speed Digital Subscriber LineÜ technique. The digital data modulator device (MOD) comprises a detection circuit (MDET) for detecting incoming idle ATM cells, and the cascade coupling of a null data cell generator (NUL), a trellis code modulator (TCM), a data encoder or mapper (MMAP), a constellation points rotation circuit (MRAN) for rotating constellation points and a constellation points shifting circuit (MTRN) for shifting constellation points to lower power points. The modulator further comprises a control circuit (MCTR) for controlling the operation of the null data cell generator, of the rotation circuit and of the shifting circuit upon detection of idle data. The digital data demodulator device (DMOD) comprises a detection circuit (DDET) for detecting received null data, and the cascade coupling of a de-shifting circuit (DTRN) for shifting constellation points with the lowest power back to points corresponding to null data cells, a de-rotation circuit (DRAN) for de-rotating the constellation points, a data decoder or de-mapper (DMAP) and a trellis code de-modulator (TCD). The demodulator further comprises a control circuit (DCTR) adapted to control the operation of the shifting circuit and of the rotation circuit upon detection of received null data. By associating with idle data constellation points shifted to the low power condition, the transmission power is minimized for idle data. Furthermore, by randomly rotating the constellation points of lowest power around the origin of the constellation diagram, training and tracking of the frequency equalizer (FEQ) in the demodulator is simplified while not increasing the transmission power. It is also avoided that all idle data symbols are represented by in-phase carriers which would otherwise result to a high crest factor in a multi-carrier systems. <IMAGE> <IMAGE> <IMAGE>
Agent for dyeing keratin containing fibers
Preparations for oligonucleotide transfer
Agent for dyeing fibres containing keratin
Mailer - postal service interfaces
Method for filling, apparatus for filling, and container for filling and packaging
Preventives or remedies for heart failure
A blast-protective window construction
Multiple document creation method and system
Mutation associated with epilepsy
Method and apparatus for performing percutaneous thromboembolectomies
Heat sink with flanged portions and spaced apart metal radiating fins
Microwave-based process for dental casting
Planetary ratchet wrench and pipe cutting tool
Front drum adjustment mechanism for a feederhouse on an agricultural combine
Method for making a modular integrated apparatus for heat dissipation
Shower cap with elastic strap suspension device
Method and apparatus for calibrating a dissolved oxygen analyzer
Apparatus and process for forming a laid fibrous web with enhanced basis weight capability