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公开(公告)号:US06320903B1
公开(公告)日:2001-11-20
申请号:US09147744
申请日:1999-06-07
申请人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenbert , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
发明人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenbert , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
IPC分类号: H03H730
CPC分类号: H04L25/03159 , H04L1/0065 , H04L1/0071 , H04L27/2649 , H04L27/2656 , H04L27/2657 , H04L27/2662 , H04L2025/03414 , H04L2025/03522
摘要: A multi-carrier transmission system using orthogonal carriers with high order QAM constellations for the transmission of a plurality of bits per carrier and symbol. The system uses some method for the determination of an inverse channel model to be used in the equalization process. In the frequency domain, this is normally based on an estimate of the channel attenuation and phase for each carrier. A simplified method of equalization is provided which uses data at the symbol carrier input and output to adaptively estimate an inverse channel model.
摘要翻译: 一种使用具有高阶QAM星座的正交载波用于每个载波和符号的多个比特的传输的多载波传输系统。 该系统使用一些方法来确定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。 提供了一种简化的均衡方法,其使用符号载波输入和输出端的数据来自适应地估计反向信道模型。
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公开(公告)号:US07039020B1
公开(公告)日:2006-05-02
申请号:US09529427
申请日:1998-10-27
申请人: Gunnar Bahlenberg , Daniel Bengtsson , Siwert Hakansson , Anders Isaksson , Lars-Ake Isaksson , Mikael Isaksson , Magnus Johansson , Mauritz Lahti , Lis-Marie Ljunggren , Hans Lundberg , Tomas Nordstrom , Lennart Olsson , Sven-Rune Olofsson , Tomas Stefansson , Hans Oman , Goran Okvist , Per Odling , Petra Dentgen , Franck Sjöberg
发明人: Gunnar Bahlenberg , Daniel Bengtsson , Siwert Hakansson , Anders Isaksson , Lars-Ake Isaksson , Mikael Isaksson , Magnus Johansson , Mauritz Lahti , Lis-Marie Ljunggren , Hans Lundberg , Tomas Nordstrom , Lennart Olsson , Sven-Rune Olofsson , Tomas Stefansson , Hans Oman , Goran Okvist , Per Odling , Petra Dentgen , Franck Sjöberg
IPC分类号: H04J1/00
CPC分类号: H04B3/23
摘要: The hybrid circuit can be used to substantially reduce near echo signals. The circuit includes a balanced 2-wire to 4-wire hybrid for interconnecting a two wire receive path and a two wire transmit path to a two wire transmission line. The two wire receive path connects the balanced hybrid to an A/D converter and the two wire transmit path connects a D/A converter to the balanced hybrid. The two wire receive path contains a filter, dimensioned to remove signals transmitted from the D/A converter. The invention is particularly adapted for use with FDD and OFDD.
摘要翻译: 混合电路可以用于大大减少近回波信号。 该电路包括用于将两线接收路径和两线传输路径互连到双线传输线的平衡的2线至4线混合。 两线接收路径将平衡混合器连接到A / D转换器,并且双线传输路径将D / A转换器连接到平衡混合器。 两线接收路径包含滤波器,其尺寸用于去除从D / A转换器发送的信号。 本发明特别适用于FDD和OFDD。
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公开(公告)号:US06181714B2
公开(公告)日:2001-01-30
申请号:US09147749
申请日:1999-06-01
申请人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Thomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
发明人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Thomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
IPC分类号: H04J310
CPC分类号: H04L27/2614 , H04L27/2656 , H04L27/2657 , H04L27/2675
摘要: A multi-carrier transmission system using DMT. It is known to recover a receiver sample and 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 an FFT processor. A complex number representing the pilot carrier is then available from the FFT processor output. If an 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 synchronization is handled separately from sampling clock synchronization, although the two processes are intimately related and frame synchronization must be acquired before sampling clock synchronization.
摘要翻译: 使用DMT的多载波传输系统。 已知从保留载波,具有固定相位的导频载波恢复接收机采样和时钟。 然后,接收机中的采样时钟振荡器被相位锁定到导频载波。 多载波接收机(如DMT接收机)通常配有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处理器以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分开处理,尽管两个过程密切相关,而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:US07239687B1
公开(公告)日:2007-07-03
申请号:US09582637
申请日:1999-01-28
申请人: Sven-Rune Olofsson , Lennart Olsson , Joachim Johansson , Hans Ohman , Mikael Isaksson , Magnus Johansson , Tomas Stefansson , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Daniel Bengtsson
发明人: Sven-Rune Olofsson , Lennart Olsson , Joachim Johansson , Hans Ohman , Mikael Isaksson , Magnus Johansson , Tomas Stefansson , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Daniel Bengtsson
CPC分类号: H04M11/062
摘要: When delivering a broadband service, such as xDSL, without inband POTS, it is necessary to separate the analogue POTS signal and the xDSL signal from each other at both the CO (Central Office) and the CP (Customer's Premises). This can be achieved by using an active POTS splitter. The present invention incorporates test functionality for the line between the CP and the CO, or ONU (Optical Network Unit), in the POTS splitter. This enables two-sided measurements on the line, both during installation and during operation. The measurements are performed at the CO and upon request, or when the test device automatically sends a test message/signal. In this way there is no need for field technicians at the CP side. The POTS splitter can have a unique identity code that is transmitted to the CO each time a test is started, or on receipt of a request from the CO.
摘要翻译: 在提供无带宽POTS等宽带业务(如xDSL)的情况下,有必要在CO(中心局)和CP(客户的场所)上分开模拟POTS信号和xDSL信号。 这可以通过使用活动的POTS分离器来实现。 本发明包括在POTS分离器之间的CP和CO之间的线路的测试功能,或ONU(光网络单元)。 这可以在安装和运行期间在线进行双面测量。 测量在CO和根据请求执行,或当测试设备自动发送测试消息/信号时执行。 这样就不需要在CP方面的现场技术人员。 POTS分离器可以具有唯一的身份码,每当测试开始时,或者在接收到来自CO的请求时,它被传送到CO。
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公开(公告)号:US06493395B1
公开(公告)日:2002-12-10
申请号:US09147758
申请日:1999-06-02
申请人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
发明人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
IPC分类号: H04L512
CPC分类号: H04L27/2657 , H04L27/2656 , H04L27/2675
摘要: A multi-carrier transmission system using orthogonal carriers with high order QAM constellations for the transmission of multiple bits per carrier and symbol. Such systems place high demands on the synchronization of the receiver with the transmitter. The maximum permitted deviation from exact synchronization is usually a small fraction of a sampling interval. A reserve 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 neighboring carriers on the pilot carrier.
摘要翻译: 一种使用具有高阶QAM星座的正交载波用于传输每个载波和符号的多个比特的多载波传输系统。 这样的系统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。 通常,作为给定固定相的导频载波的预留载波通常用作参考以实现这种高精度。 接收机采样时钟振荡器与导频载波锁相。 因此,需要估计导频载波的相位。 使用带通滤波器来恢复导频载波,无论DMT信号的帧结构如何,都不会消除相邻载波对导频载波的影响。
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公开(公告)号:US06438174B1
公开(公告)日:2002-08-20
申请号:US09147742
申请日:1999-06-04
申请人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
发明人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
IPC分类号: H04L512
CPC分类号: H04L5/006 , H04L1/0065 , H04L1/0071 , H04L5/0007 , H04L5/0046
摘要: A multi-carrier transmission system such as a DMT based VDSL system. The system uses orthogonal carriers with high order QAM constellations for the transmission of multiple bits per carrier and symbol. This estimate includes digital receiver and transmitter units with the receiver unit including a symbol detection unit. This system is adapted to determine a parameter for each single carrier with the parameter being indicative of a deviation of a received signal from a corresponding constellation point. It compares the parameter with an upper lower limit and if the parameter is outside the limits, changes the constellation used to modulate the carrier to a neighboring constellation. The symbol detection unit may be used to determine a parameter such as the ratio d2/&sgr;2, where d is the shortest distance between neighboring constellations, &sgr; is a standard deviation and &sgr;2 is the variance of the deviations of the input and output signal values of the symbol detection unit.
摘要翻译: 一种多载波传输系统,如基于DMT的VDSL系统。 该系统使用具有高阶QAM星座的正交载波,用于每个载波和符号的多个比特的传输。 该估计包括具有包括符号检测单元的接收器单元的数字接收器和发射器单元。 该系统适于确定每个单载波的参数,其中该参数指示接收到的信号与对应星座点的偏差。 它将参数与上限进行比较,如果参数超出限制,则将用于调制载波的星座更改为相邻星座。 符号检测单元可以用于确定诸如d2 / sigma2之类的参数,其中d是相邻星座之间的最短距离,σ是标准偏差,而sigma2是输入和输出信号值的偏差的方差 符号检测单元。
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公开(公告)号:US06359926B1
公开(公告)日:2002-03-19
申请号:US09147748
申请日:1999-06-01
申请人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
发明人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
IPC分类号: H04L704
CPC分类号: H04L1/0025 , H04L1/0059 , H04L1/0071 , H04L27/2657 , H04L27/2662 , H04L27/2675
摘要: A two-way multi-carrier transmission system, such as a DMT system. If there are dynamic changes in the transmission parameters, synchronization must be maintained between the transmitter and the receiver when the transmission parameters changed. The first stage of such a process requires that the changes of parameter be notified by one transceiver to others involved in an active communication process over a slow transmission channel such as the control channel. Subsequently, the synchronization transceiver is adjusted simultaneously, i.e., from a predetermined DMT symbol. Such adjustments in time synchronization must be achieved with a minimum of overhead.
摘要翻译: 一种双向多载波传输系统,如DMT系统。 如果传输参数有动态变化,传输参数变化时,必须在发射机和接收机之间保持同步。 这种过程的第一阶段要求将参数的变化通过诸如控制信道的慢速传输信道由一个收发机通知参与有源通信过程中的其他人。 随后,同步收发器被同时调整,即从预定的DMT符号调整。 时间同步中的这种调整必须以最小的开销来实现。
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公开(公告)号:US6160820A
公开(公告)日:2000-12-12
申请号:US147755
申请日:1999-06-14
申请人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
发明人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
CPC分类号: H04L5/006 , H04L5/0007 , H04L5/0037 , H04L5/0046
摘要: A multi-carrier transmission system, particularly a discrete multi-tone (DMT) system. Data is transmitted between two transceivers using a plurality of carriers. The frequency bandwidth of the system is divided between the plurality of carriers. The transmission system is adapted for operation in a heterogeneous network including a number of subscriber equipments having different channel characteristics and coexisting on the same cable. The length of cable for each subscriber terminal varies in relation to its respective location. The transmission system includes an allocation device for allocating the traffic of subscriber equipments having a shorter length of cable to tones starting from a higher frequency band of the system bandwidth.
摘要翻译: PCT No.PCT / SE97 / 01461 Sec。 371日期1999年6月14日第 102(e)1999年6月14日PCT PCT 1997年9月1日PCT公布。 出版物WO98 / 10556 日期1998年3月12日一种多载波传输系统,特别是离散多音(DMT)系统。 使用多个载波在两个收发器之间传输数据。 系统的频率带宽在多个载波之间划分。 传输系统适用于异构网络中的操作,包括具有不同信道特性的多个用户设备并且在同一电缆上共存。 每个用户终端的电缆长度相对于其各自的位置而变化。 传输系统包括分配装置,用于将具有较短电缆长度的用户设备的业务分配到从系统带宽的较高频带开始的音调。
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公开(公告)号:US06865232B1
公开(公告)日:2005-03-08
申请号:US09147750
申请日:1997-07-15
申请人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
发明人: Mikael Isaksson , Magnus Johansson , Harry Tonvall , Lennart Olsson , Tomas Stefansson , Hans Ohman , Gunnar Bahlenberg , Anders Isaksson , Goran Okvist , Lis-Marie Ljunggren , Tomas Nordstrom , Lars-Ake Isaksson , Daniel Bengtsson , Siwert Hakansson , Ye Wen
CPC分类号: H04L1/0025 , H04L1/0059 , H04L1/0071 , H04L5/0007 , H04L5/0046 , H04L5/006 , H04L25/03159 , H04L27/2656 , H04L27/2657 , H04L27/2662 , H04L27/3461 , H04L2025/03414 , H04L2025/03522
摘要: A multi-carrier transmission system has a plurality of transceivers, each having a receiver and a transmitter. Data is transmitted between the transceivers by modulating the data onto a multiplicity of carrier waves in the form of multi-bit symbols, wherein each carrier wave constitutes a channel, and wherein the number of bits per symbol (the bit loading), varies between channels and, within a channel, with time, so that each channel has associated therewith a bit loading parameter. In operation, the multi-carrier system is adapted to synchronously update, at the transceivers, the bit loading parameters associated with each channel by transmission of data over a control channel, in that the control channel is established, at system start-up, on a predetermined one of the multiplicity of carrier waves whose identity is known to the transceivers, and in that the control channel is, after start-up, changed from the predetermined channel to a further channel, selected by the first transceiver on the basis of channel characteristics.
摘要翻译: 多载波传输系统具有多个收发机,每个收发机具有接收机和发射机。 通过以多位符号的形式将数据调制到多个载波上,在收发器之间传输数据,其中每个载波构成一个信道,并且其中每个符号的比特数(比特加载)在信道之间变化 并且在频道内,随着时间,使得每个频道与其相关联地加载参数。 在操作中,多载波系统适于在收发机处通过控制信道上的数据传输来同步更新与每个信道相关联的比特加载参数,因为在系统启动时建立控制信道 多个载波的预定的一个载波,其身份对于收发机是已知的,并且控制信道在启动之后从预定信道改变到由第一收发信机基于信道选择的另一个信道 特点
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公开(公告)号:US06751261B1
公开(公告)日:2004-06-15
申请号:US09147230
申请日:1999-02-09
申请人: Lennart Olsson , Gunnar Bahlenberg , Daniel Bengtsson , Siwert Håkansson , Anders Isaksson , Lars-Ake Isaksson , Mikael Isaksson , Magnus Johansson , Mauritz Lahti , Lis-Marie Ljunggren , Hans Lundberg , Tomas Nordstrom , Sven-Rune Olofsson , Tomas Stefansson , Hans Oman , Goran Okvist
发明人: Lennart Olsson , Gunnar Bahlenberg , Daniel Bengtsson , Siwert Håkansson , Anders Isaksson , Lars-Ake Isaksson , Mikael Isaksson , Magnus Johansson , Mauritz Lahti , Lis-Marie Ljunggren , Hans Lundberg , Tomas Nordstrom , Sven-Rune Olofsson , Tomas Stefansson , Hans Oman , Goran Okvist
IPC分类号: H04L506
CPC分类号: H04L27/2662 , H04L27/2657 , H04L27/2672 , H04L27/2678
摘要: 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. In a multi-carrier system of the OFDM type, an adaptive channel equalizer, operating in the frequency domain, is often used. The internal parameters in such an equalizer contain, in addition to information about the characteristics of the channel, information which can be interpreted as the time deviation between the sampling clocks of the transmitter and the receiver. The present invention utilizes this information to control the sampling clock of the receiver in a more robust way than has previously been possible with known techniques. 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.
摘要翻译: 对于OFDM系统,频域数据是接收的时域OFDM帧的傅里叶变换。 必须在接收机处与发射机同步地采样时域帧,使得每个接收的帧包含来自仅一个发射帧的数据。 为了保持帧的正交性,保持该同步是至关重要的。 使用循环前缀的OFDM类型的典型多载波系统当与精确帧同步的偏差很小时,允许维持正交性。 由于信令间隔包括作为帧的一部分的重复的整个帧和循环前缀,所以在信令间隔内采样的帧将仅包含来自一个帧的数据。 由于信令间隔大于帧周期,所以在帧对齐中给出了一些余地。 在OFDM类型的多载波系统中,经常使用在频域中工作的自适应信道均衡器。 除了关于信道特性的信息之外,这种均衡器中的内部参数还包含可被解释为发射机和接收机的采样时钟之间的时间偏差的信息。 本发明利用该信息以比先前已知技术可能的更可靠的方式来控制接收机的采样时钟。 本发明特别适用于ADSL和VDSL调制解调器,可用于通过铜网络提供宽带接入。 本发明还涉及用于在无线电信道上传输的移动和半移动系统中的宽带传输。
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