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公开(公告)号：WO9839886A3
公开(公告)日：1998-12-10
申请号：PCT/SE9800354
申请日：1998-02-27
Applicant: TELIA AB , OLSSON LENNART , BAHLENBERG GUNNAR , BENGTSSON DANIEL , HAAKANSSON SIWERT , ISAKSSON ANDERS , ISAKSSON LARS AAKE , ISAKSSON MIKAEL , JOHANSSON MAGNUS , LATHI MAURITZ , LJUNGGREN LIS MARIE , LUNDBERG HANS , NORDSTROEM TOMAS , OLOFSSON SVEN RUNE , STEFANSSON TOMAS , OEHMAN HANS , OEKVIST GOERAN
Inventor： OLSSON LENNART , BAHLENBERG GUNNAR , BENGTSSON DANIEL , HAAKANSSON SIWERT , ISAKSSON ANDERS , ISAKSSON LARS-AAKE , ISAKSSON MIKAEL , JOHANSSON MAGNUS , LATHI MAURITZ , LJUNGGREN LIS-MARIE , LUNDBERG HANS , NORDSTROEM TOMAS , OLOFSSON SVEN-RUNE , STEFANSSON TOMAS , OEHMAN HANS , OEKVIST GOERAN
CPC classification number: H04L27/2662 , H04L27/2657 , H04L27/2672 , H04L27/2678
Abstract: With OFDM systems the frequency domain data is the Fourier transform of the received time domain OFDM frames. The time domain frames must be sampled, at the receiver, in synchronism with the transmitter, so that each received frame contains data from only a single transmitted frame. It is vital for this synchronism to be maintained in order to maintain the orthogonality of the frames. A typical multi-carrier system, of the OFDM type, which uses a cyclic prefix permits orthogonality to be maintained when there is a small deviation from exact frame synchronisation. Because the signalling interval includes both an entire frame and the cyclic prefix, which is a repetition of part of the frame, a frame sampled within the signalling interval will contain data from only one frame. Since the signalling interval is greater than the frame period, this gives some leeway in frame alignment. The present invention provides a mechanism for achieving frame synchronisation, in the frequency domain, by utilising this fact. The first step in synchronising a receiver with a transmitter, on signal acquisition, is to determine the interval in which orthogonality exists. Once this has been achieved an argument function is calculated from the received frame. This argument function can then be used to improve the synchronisation. The present invention is particularly suitable for use in ADSL and VDSL modems which can be used to give broadband access over copper networks. The invention is also of relevance to broadband transmission in mobile and semi-mobile systems for transmission over the radio channels.
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公开(公告)号：WO9810549A3
公开(公告)日：1998-05-22
申请号：PCT/SE9701454
申请日：1997-09-01
Applicant: TELIA AB , ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
Inventor： ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
CPC classification number: H04L1/0025 , H04L1/0059 , H04L1/0071 , H04L27/2657 , H04L27/2662 , H04L27/2675
Abstract: In a two-way multi-carrier transmission system, such as a DMT system, in which there can be dynamic changes in the transmission parameters, some means must be provided for maintaining synchronisation between transmitter and receiver when the transmission parameters change. The first stage of such a process requires that changes of parameter be notified by one transceiver to the other, involved in an active communication process, over a slow transmission channel, the control channel. Subsequently the synchronisation of the transceivers is adjusted simultaneously, i.e. from a predetermined DMT symbol. Such adjustements in time synchronisation must be achieved with a minimum of overhead. 00000
Abstract translation: 在诸如DMT系统的双向多载波传输系统中，其中可以在传输参数中存在动态变化，当传输参数改变时，必须提供一些用于在发射机和接收机之间保持同步的装置。 这种过程的第一阶段要求通过慢速传输信道，控制信道将参数的变化通过一个收发器通知给另一个收发器，参与主动通信过程。 随后，收发器的同步被同时调整，即从预定的DMT符号调整。 时间同步的这种调整必须以最小的开销来实现。 00000
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公开(公告)号：WO9810554A3
公开(公告)日：1998-05-07
申请号：PCT/SE9701459
申请日：1997-09-01
Applicant: TELIA AB , ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS MARIE , NORDSTROEM TOMAS , ISAKSSON LARS AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
Inventor： ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
CPC classification number: H04L5/006 , H04L1/0065 , H04L1/0071 , H04L5/0007 , H04L5/0046
Abstract: The invention provides a multi-carrier transmission system, for example, a DMT based VDSL system, using orthogonal carriers with high order QAM constellations for the transmission of multiple bits per carrier and symbol, said system including digital receiver and transmitter units, said receiver unit including a symbol detection unit, characterised in that said system is adapted to determining a parameter for each single carrier, said parameter being indicative of a deviation of a received signal from a corresponding constellation point; comparing the parameter with an upper and lower limit; and, if the parameter is outside said limits, changing the constellation used to modulate the carrier to a neighbouring constellation. The symbol detection unit may be used to determine the parameter which may be a ratio d?2/σ2¿, where d is the shortest distance between neighbouring constellations, σ is a standard deviation, and σ2 is the variance of the deviations of the input and output signal values of said symbol detection unit.
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14.发明申请
公开(公告)号：WO9810551A3
公开(公告)日：1998-05-07
申请号：PCT/SE9701456
申请日：1997-09-01
Applicant: TELIA AB , ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS MARIE , NORDSTROEM TOMAS , ISAKSSON LARS AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE , OEDLING PER
Inventor： ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE , OEDLING PER
CPC classification number: H04L5/0046 , H04L1/0065 , H04L1/0071 , H04L5/0007 , H04L5/006
Abstract: The invention provides a multi-carrier transmission system, for example, a DMT system, in which channel information is transmitted between two transceivers using a plurality of sub-carriers modulated with symbols, each of which represents a multiplicity of bits, each of said transceivers including a receiver and a transmitter, in which a fixed maximum value is determined for the number of bits for each symbol, and in which the system is adapted to determine the bit capacity per symbol of each of said plurality of sub-carriers, and to increase the number of bits represented by a symbol, transmitted over those sub-carriers having a capacity less than the fixed maximum value, to said maximum value by the addition of channel coding bits. The fixed maximum value for the number of bits for each symbol may be determined on the basis of the bit capacity of that one of the sub-carriers having the highest theoretical bit capacity and may be at least as large as said theoretical bit capacity.
Abstract translation: 本发明提供了一种多载波传输系统，例如一种DMT系统，其中使用用符号调制的多个子载波在两个收发信机之间传输信道信息，每个子载波代表多个比特，每个所述收发信机 包括一个接收机和一个发射机，其中为每个符号的比特数确定一个固定的最大值，并且其中该系统适合于确定所述多个子载波中的每一个的每个符号的比特容量，以及 通过增加信道编码比特，将在具有小于固定最大值的容量的那些子载波上发送的由码元表示的比特的数量增加到所述最大值。 每个符号的比特数的固定最大值可以基于具有最高理论比特容量的那个子载波的比特容量来确定，并且可以至少与所述理论比特容量一样大。
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公开(公告)号：WO9839872A3
公开(公告)日：2000-08-24
申请号：PCT/SE9800353
申请日：1998-02-27
Applicant: TELIA AB , OLSSON LENNART , BAHLENBERG GUNNAR , BENGTSSON DANIEL , HAAKANSSON SIWERT , ISAKSSON ANDERS , ISAKSSON LARS AAKE , ISAKSSON MIKAEL , JOHANSSON MAGNUS , LAHTI MAURITZ , LJUNGGREN LIS MARIE , LUNDBERG HANS , NORDSTROEM TOMAS , OLOFSSON SVEN RUNE , STEFANSSON TOMAS , OEMAN HANS , OEKVIST GOERAN
Inventor： OLSSON LENNART , BAHLENBERG GUNNAR , BENGTSSON DANIEL , HAAKANSSON SIWERT , ISAKSSON ANDERS , ISAKSSON LARS-AAKE , ISAKSSON MIKAEL , JOHANSSON MAGNUS , LAHTI MAURITZ , LJUNGGREN LIS-MARIE , LUNDBERG HANS , NORDSTROEM TOMAS , OLOFSSON SVEN-RUNE , STEFANSSON TOMAS , OEMAN HANS , OEKVIST GOERAN
CPC classification number: H04L27/2662 , H04L27/2657 , H04L27/2672 , H04L27/2678
Abstract: The present invention relates to a receiver for use in an OFDM type transmission system, in which data is transmitted in frames. Each frame has a cyclic prefix which is a repetition of part of the frame. Control means are provided and the control means controls a sampling oscilator. The control means include estimation means for estimating timing deviations of the sampling clock. The estimation means operates entirely on frequency domain input data.
Abstract translation: 本发明涉及一种用于OFDM类型传输系统的接收机，其中数据以帧的形式发送。 每个帧具有循环前缀，其是帧的一部分的重复。 提供控制装置，并且控制装置控制采样振荡器。 控制装置包括用于估计采样时钟的定时偏差的估计装置。 估计装置完全在频域输入数据上运行。
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Patent Agency Ranking16.发明申请
公开(公告)号：WO9810548A3
公开(公告)日：1998-06-04
申请号：PCT/SE9701453
申请日：1997-09-01
Applicant: TELIA AB , ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS MARIE , NORDSTROEM TOMAS , ISAKSSON LARS AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
Inventor： ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
CPC classification number: H04L27/2657 , H04L27/2656 , H04L27/2675
Abstract: Modern multi-carrier transmission systems, using orthogonal carriers with high order QAM constellations for the transmission of multiple bits per carrier and symbol, place high demands on the synchronisation of the receiver with the transmitter. The maximum permitted deviation from exact synchronisation is usually a small fraction of a sampling interval. A reserved carrier, the pilot carrier, which is given a fixed phase, is usually used as the reference to achieve this high accuracy. The receiver sampling clock oscillator is phase-locked to the pilot carrier. It is, therefore, necessary to estimate the phase of the pilot carrier. Using a bandpass filter to recover the pilot carrier, regardless of the frame structure of the DMT signal, does not eliminate the influence of neighbouring carriers on the pilot carrier.
Abstract translation: 现代多载波传输系统使用具有高阶QAM星座的正交载波来传输每载波和符号的多个比特，这对接收机与发射机的同步提出了很高的要求。 精确同步的最大允许偏差通常是采样间隔的一小部分。 一个保留的载波，给定一个固定相位的导频载波通常用作参考来实现这个高精度。 接收器采样时钟振荡器被锁相到导频载波。 因此，有必要估计导频载波的相位。 无论DMT信号的帧结构如何，使用带通滤波器来恢复导频载波都不会消除相邻载波对导频载波的影响。
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17.发明申请
公开(公告)号：WO9810546A3
公开(公告)日：1998-06-04
申请号：PCT/SE9701451
申请日：1997-09-01
Applicant: TELIA AB , ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON THOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS MARIE , NORDSTROEM TOMAS , ISAKSSON LARS AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
Inventor： ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON THOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
CPC classification number: H04L27/2614 , H04L27/2656 , H04L27/2657 , H04L27/2675
Abstract: In multi-carrier transmission systems using, for example, DMT, it is known to recover a receiver sampling clock from a reserved carrier, a pilot carrier, having a fixed phase. A sampling clock oscillator in a receiver is then phase-locked to the pilot carrier. Multi-carrier receivers, such as DMT receivers, are normally equipped with a FFT processor. A complex number representing the pilot carrier is then available from the FFT processor output. If a FFT processor is not available, a one-frequency DFT processor can be provided to produce a complex estimate of the pilot carrier. In a DMT system, frame synchronisation is handled separately from sampling clock synchronisation, although the two processes are intimately related and frame synchronisation must be acquired before sampling clock synchronisation.
Abstract translation: 在使用例如DMT的多载波传输系统中，已知从具有固定相位的保留载波，导频载波恢复接收器采样时钟。 接收器中的采样时钟振荡器然后被锁相到导频载波。 多载波接收机，例如DMT接收机，通常配备有FFT处理器。 然后可以从FFT处理器输出获得表示导频载波的复数。 如果FFT处理器不可用，则可以提供单频DFT处理器来产生导频载波的复杂估计。 在DMT系统中，帧同步与采样时钟同步是分开处理的，虽然这两个过程密切相关，并且在采样时钟同步之前必须获取帧同步。
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公开(公告)号：WO9810550A3
公开(公告)日：1998-06-18
申请号：PCT/SE9701455
申请日：1997-09-01
Applicant: TELIA AB , ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
Inventor： ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
CPC classification number: H04L27/2647
Abstract: When a multi-carrier signal is received, it is sampled and digitised before FFT processing, (or wavelet transform processing). Multi-carrier signals consist of many narrow band carrier waves which convey data via a wide band channel. The amplitude distribution of the sum of all the individual carriers is Gaussian. This means that high amplitudes occur with low probability. At the present time, analogue to digital convertors have a limited dynamic range. It is, therefore, normal practice to provide a compromise between cutting and quantisation noise. This means that the adverse effects of a coarse quantisation have to be balanced against signal distortions caused by loss of the low probability high amplitude signals. 00000
Abstract translation: 当接收到多载波信号时，在FFT处理（或小波变换处理）之前对其进行采样和数字化处理。 多载波信号由许多通过宽带信道传送数据的窄带载波组成。 所有单个载波的和的幅度分布是高斯。 这意味着高幅度以低概率发生。 目前，模数转换器的动态范围有限。 因此，在切割和量化噪声之间提供妥协是正常的做法。 这意味着粗略量化的不利影响必须与由低概率高幅度信号的损失引起的信号失真相平衡。 00000
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19.发明申请
公开(公告)号：WO9810555A3
公开(公告)日：1998-06-04
申请号：PCT/SE9701460
申请日：1997-09-01
Applicant: TELIA AB , ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS MARIE , NORDSTROEM TOMAS , ISAKSSON LARS AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
Inventor： ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
CPC classification number: H04L25/03159 , H04L1/0065 , H04L1/0071 , H04L27/2649 , H04L27/2656 , H04L27/2657 , H04L27/2662 , H04L2025/03414 , H04L2025/03522
Abstract: Modern multi-carrier techniques using orthogonal carriers with high order QAM constellations for the transmission of a plurality of bits per carrier and symbol, use some method for the determination of an inverse channel model to be used in an equalisation process. In the frequency domain, this is normally based on an estimate of the channel attenuation and phase for each carrier. The present invention provides a simplified method of equalisation that uses data at the symbol detector input and output to adaptively estimate an inverse channel model.
Abstract translation: 使用具有高阶QAM星座的正交载波用于每载波和符号传输多个比特的现代多载波技术使用某种方法来确定将在均衡过程中使用的反向信道模型。 在频域中，这通常基于每个载波的信道衰减和相位的估计。 本发明提供了一种简化的均衡方法，该方法使用符号检测器输入和输出处的数据来自适应地估计逆信道模型。
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20.发明申请
公开(公告)号：WO9810553A3
公开(公告)日：1998-05-07
申请号：PCT/SE9701458
申请日：1997-09-01
Applicant: TELIA AB , ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS MARIE , NORDSTROEM TOMAS , ISAKSSON LARS AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
Inventor： ISAKSSON MIKAEL , JOHANSSON MAGNUS , TONVALL HARRY , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , NORDSTROEM TOMAS , ISAKSSON LARS-AAKE , BENGTSSON DANIEL , HAAKANSSON SIWERT , WEN YE
CPC classification number: H04L5/006 , H04L1/0065 , H04L1/0071 , H04L5/0007 , H04L5/0046 , H04L27/3461
Abstract: In certain types of transmission system using nQAM it may be desirable to use a control channel superimposed on a nQAM data channel. In such circumstances it is very desirable to be able to separate control channel data from user data without using a higher level protocol layer. For applications in multi-carrier systems with variable bit-loading it is particularly desirable that the control channel data be separable from user data when the value of n, i.e. the bit-loading, or constellation identifier are unknown. Binary data is transmitted using nQAM modulation. The binary data comprises both user data and control data. This means that a control channel is superimposed on a user data channel within the same nQAM constellation. Separation of said control data is facilitated by arranging control data points to have either unique phase, or unique amplitude, values. These unique values are not employed for user data points.
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