Global Patent Index - EP 0990324 A1

EP 0990324 A1 2000-04-05 - IMPROVED METHOD FOR PARTIALLY MODULATING AND DEMODULATING DATA IN A MULTI-CARRIER TRANSMISSION SYSTEM

Title (en)

IMPROVED METHOD FOR PARTIALLY MODULATING AND DEMODULATING DATA IN A MULTI-CARRIER TRANSMISSION SYSTEM

Title (de)

VERBESSERTES VERFAHREN ZUM TEILWEISE MODULIEREN UND DEMODULIEREN VON DATEN IN EINEM MEHRTRÄGER-ÜBERTRAGUNGSSYSTEM

Title (fr)

PROCEDE AMELIORE DE MODULATION ET DEMODULATION PARTIELLES DE DONNEES DANS UN SYSTEME DE TRANSMISSION A PORTEUSES MULTIPLES

Publication

EP 0990324 A1 (EN)

Application

EP 97925573 A

Priority

US 9708209 W

Abstract (en)

[origin: WO9853572A1] A decoder (200) and an encoder (300) for extracting a subset of symbols from, or inserting a subset of symbols into, a communication channel (333) in which M symbols are transmitted as the amplitudes of M sinusoidal carriers. The decoder (200) recovers K symbols, Sp...Sp+K-1, from an analog signal generated by modulating M sinusoidal carriers for a frame period. Each carrier is modulated with an amplitude proportional to the value of one of M symbols, the i<th> carrier being modulated by symbol Si. The K symbols are a contiguous subset of the M symbols. The decoder (200) includes a down-converter (201, 211, 202, 212) for down-converting the modulated signal on the communication channel to generate a down-converted signal in which the carriers corresponding to Sp...Sp+K-1 occupy frequencies starting from O. An analog-digital converter (203, 313) generates K time-domain samples in each frame period from the down-converted signal. These time-domain samples are converted to K frequency-domain values representing the symbols Sp...Sp+K-1 by a time-domain to frequency-domain overlapped transform. The encoder (300) encodes K symbols, S1...SK, as the amplitudes of K sinusoidal carriers, the K sinusoidal carriers comprising a contiguous block of carriers in a signal comprising M sinusoidal carriers in which each of the carriers is modulated by a signal having an amplitude determined by the value of one of the symbols for a time equal to one frame period. The encoder (300) includes a frequency-domain to time-domain overlapped transform (302, 312) for generating K time-domain samples from the K symbols, the time-domain samples representing a modulated carrier comprising K sinusoidal carriers, each of the carriers being modulated by a signal having an amplitude determined by the value of one of the K symbols. A digital-to-analog converter (304, 314) converts the K time-domain samples to an analog signal. The analog signal is then up-converted such that the sinusoidal carrier modulated by S1 has a frequency equal to the p<th> carrier of the M sinusoidal carriers, wherein p>/=0.

IPC 1-7 (main, further and additional classification)

H04K 1/10; H04L 27/28

IPC 8 full level (invention and additional information)

H04J 11/00 (2006.01); H04L 5/02 (2006.01); H04L 27/26 (2006.01)

CPC (invention and additional information)

H04L 5/023 (2013.01); H04L 27/2633 (2013.01); H04L 27/2649 (2013.01)

Citation (search report)

See references of WO 9853572A1

Designated contracting state (EPC)

DE ES FR GB

EPO simple patent family

WO 9853572 A1 19981126; AU 3067397 A 19981211; AU 743020 B2 20020117; CA 2289529 A1 19981126; EP 0990324 A1 20000405; JP 2002507337 A 20020305

INPADOC legal status


2003-06-11 [18W] WITHDRAWN

- Effective date: 20030416

2000-04-12 [RIN1] INVENTOR (CORRECTION)

- Inventor name: SANDBERG, STUART, D.

2000-04-12 [RIN1] INVENTOR (CORRECTION)

- Inventor name: HELLER, PETER, N.

2000-04-12 [RIN1] INVENTOR (CORRECTION)

- Inventor name: TZANNES, MICHAEL

2000-04-05 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 19991110

2000-04-05 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): DE ES FR GB