SE9603196L - Improvements to, or with respect to, multi-carrier systems - Google Patents

Improvements to, or with respect to, multi-carrier systems

Info

Publication number
SE9603196L
SE9603196L SE9603196A SE9603196A SE9603196L SE 9603196 L SE9603196 L SE 9603196L SE 9603196 A SE9603196 A SE 9603196A SE 9603196 A SE9603196 A SE 9603196A SE 9603196 L SE9603196 L SE 9603196L
Authority
SE
Sweden
Prior art keywords
parameter
carrier wave
detection unit
symbol detection
constellation
Prior art date
Application number
SE9603196A
Other languages
Swedish (sv)
Other versions
SE506643C2 (en
SE9603196D0 (en
Inventor
Mikael Isaksson
Magnus Johansson
Harry Erland Tonvall
Lennart Olsson
Tomas Stefansson
Hans Oehman
Kjell Gunnar Bahlenberg
Anders Imanuel Isaksson
Sven Goeran Oekvist
Karin Lis-Mari Ljunggren
Tomas Nordstroem
Lars-Aake Isaksson
Daniel Bengtsson
Wen Ye
Siwert Haakansson
Original Assignee
Telia Ab
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to SE9602074A priority Critical patent/SE9602074D0/en
Application filed by Telia Ab filed Critical Telia Ab
Priority to SE9603196A priority patent/SE506643C2/en
Publication of SE9603196D0 publication Critical patent/SE9603196D0/en
Priority to JP51256198A priority patent/JP4016126B2/en
Priority to PCT/SE1997/001459 priority patent/WO1998010554A2/en
Priority to AT97939279T priority patent/ATE228286T1/en
Priority to US09/147,742 priority patent/US6438174B1/en
Priority to EP97939279A priority patent/EP0922345B1/en
Priority to DE69717285T priority patent/DE69717285T2/en
Publication of SE9603196L publication Critical patent/SE9603196L/en
Publication of SE506643C2 publication Critical patent/SE506643C2/en
Priority to NO990776A priority patent/NO990776L/en

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0002—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the transmission rate
    • H04L1/0003—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the transmission rate by switching between different modulation schemes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H04L27/2649—Demodulators
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H04L27/2649—Demodulators
    • H04L27/26524—Fast Fourier transform [FFT] or discrete Fourier transform [DFT] demodulators in combination with other circuits for demodulation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H04L27/2649—Demodulators
    • H04L27/26524—Fast Fourier transform [FFT] or discrete Fourier transform [DFT] demodulators in combination with other circuits for demodulation
    • H04L27/26526—Fast Fourier transform [FFT] or discrete Fourier transform [DFT] demodulators in combination with other circuits for demodulation with inverse FFT [IFFT] or inverse DFT [IDFT] demodulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] receiver or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H04L27/2649—Demodulators
    • H04L27/26532—Demodulators using other transforms, e.g. discrete cosine transforms, Orthogonal Time Frequency and Space [OTFS] or hermetic transforms
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2697—Multicarrier modulation systems in combination with other modulation techniques
    • H04L27/2698—Multicarrier modulation systems in combination with other modulation techniques double density OFDM/OQAM system, e.g. OFDM/OQAM-IOTA system
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
    • H04L27/34—Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems

Abstract

The system includes a digital receiver unit and transmission unit. The receiver unit including a symbol detection unit. The system determines a parameter for each individual carrier wave. The parameter indicate a deviation in a received signal from a corresponding constellation point. The parameter is compared with an upper and a lower limit. When the parameter is outside the limits the used constellation is altered in order to modulate the carrier wave to a neighbouring constellation. The symbol detection unit is used to determine the parameter for a carrier wave. The parameter is a ratio d2/o2, where d is the shortest distance between adjoining constellations, o is a standard deviation, and o2 is the variance in the deviations in the input and output signal values in the symbol detection unit.
SE9603196A 1996-05-24 1996-09-02 Multi-carrier wave transmission system e.g. for VDSL system SE506643C2 (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
SE9602074A SE9602074D0 (en) 1996-05-24 1996-05-24 Method for determining the bit-loading in a multicarrier system
SE9603196A SE506643C2 (en) 1996-05-24 1996-09-02 Multi-carrier wave transmission system e.g. for VDSL system
DE69717285T DE69717285T2 (en) 1996-09-02 1997-09-01 IMPROVEMENTS IN OR WITH REGARD TO MULTI-CARRIER TRANSFER SYSTEMS
AT97939279T ATE228286T1 (en) 1996-09-02 1997-09-01 IMPROVEMENTS IN, OR RELATING TO, MULTI-CARrier TRANSMISSION SYSTEMS
PCT/SE1997/001459 WO1998010554A2 (en) 1996-09-02 1997-09-01 Improvements in, or relating to, multi-carrier transmission systems
JP51256198A JP4016126B2 (en) 1996-09-02 1997-09-01 Improvement of multi-carrier transmission system
US09/147,742 US6438174B1 (en) 1996-09-02 1997-09-01 Multi-carrier transmission systems
EP97939279A EP0922345B1 (en) 1996-09-02 1997-09-01 Improvements in, or relating to, multi-carrier transmission systems
NO990776A NO990776L (en) 1996-09-02 1999-02-19 Multi-carrier transmission system using orthogonal carriers, and a method for determining a constellation for each carrier

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9602074A SE9602074D0 (en) 1996-05-24 1996-05-24 Method for determining the bit-loading in a multicarrier system
SE9603196A SE506643C2 (en) 1996-05-24 1996-09-02 Multi-carrier wave transmission system e.g. for VDSL system

Publications (3)

Publication Number Publication Date
SE9603196D0 SE9603196D0 (en) 1996-09-02
SE9603196L true SE9603196L (en) 1997-11-30
SE506643C2 SE506643C2 (en) 1998-01-26

Family

ID=26662640

Family Applications (2)

Application Number Title Priority Date Filing Date
SE9602074A SE9602074D0 (en) 1996-05-24 1996-05-24 Method for determining the bit-loading in a multicarrier system
SE9603196A SE506643C2 (en) 1996-05-24 1996-09-02 Multi-carrier wave transmission system e.g. for VDSL system

Family Applications Before (1)

Application Number Title Priority Date Filing Date
SE9602074A SE9602074D0 (en) 1996-05-24 1996-05-24 Method for determining the bit-loading in a multicarrier system

Country Status (1)

Country Link
SE (2) SE9602074D0 (en)

Also Published As

Publication number Publication date
SE506643C2 (en) 1998-01-26
SE9602074D0 (en) 1996-05-24
SE9603196D0 (en) 1996-09-02

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