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公开(公告)号：DE69723563D1
公开(公告)日：2003-08-21
申请号：DE69723563
申请日：1997-09-01
Applicant: ST MICROELECTRONICS NV
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-AKE , BENGTSSON DANIEL , HAKANSSON SIWERT , WEN YE
Abstract: 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.
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公开(公告)号：AT245324T
公开(公告)日：2003-08-15
申请号：AT97939280
申请日：1997-09-01
Applicant: ST MICROELECTRONICS NV
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-AKE , BENGTSSON DANIEL , HAKANSSON SIWERT , WEN YE
Abstract: 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.
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公开(公告)号：DE69722415D1
公开(公告)日：2003-07-03
申请号：DE69722415
申请日：1997-09-01
Applicant: ST MICROELECTRONICS NV
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-AKE , BENGTSSON DANIEL , HAKANSSON SIWERT , WEN YE
Abstract: In certain types ol transmission system using nQ,1M it may be desirable to use a control applications in muIticarrier snrstems with variable bitloading it is particularly desirible that the control channel data be separable from user data when the value of n. i.e the bitloading. or constellation identifier are unknown. Binary data is transmitted using nQAM modulation. The binary data comprises both user data and cointro,l clata. This means that a control channel is superimposed on a user data channel within the same nQAM constellation. Separation of said control data is lacilitated 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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公开(公告)号：AT241879T
公开(公告)日：2003-06-15
申请号：AT97937938
申请日：1997-09-01
Applicant: ST MICROELECTRONICS NV
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-AKE , BENGTSSON DANIEL , HAKANSSON SIWERT , WEN YE
Abstract: In certain types ol transmission system using nQ,1M it may be desirable to use a control applications in muIticarrier snrstems with variable bitloading it is particularly desirible that the control channel data be separable from user data when the value of n. i.e the bitloading. or constellation identifier are unknown. Binary data is transmitted using nQAM modulation. The binary data comprises both user data and cointro,l clata. This means that a control channel is superimposed on a user data channel within the same nQAM constellation. Separation of said control data is lacilitated 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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公开(公告)号：DE69720225D1
公开(公告)日：2003-04-30
申请号：DE69720225
申请日：1997-09-01
Applicant: ST MICROELECTRONICS NV
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-AKE , BENGTSSON DANIEL , HAKANSSON SIWERT , WEN YE
Abstract: 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.
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Patent Agency Ranking
公开(公告)号：DE69717128D1
公开(公告)日：2002-12-19
申请号：DE69717128
申请日：1997-09-01
Applicant: ST MICROELECTRONICS NV
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-AKE , BENGTSSON DANIEL , HAKANSSON SIWERT , WEN YE
Abstract: A multi-carrier transmission system. A received multi-carrier signal is sampled and digitized before FFT 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, analog to digital converters have a limited dynamic range. It is therefore normal practice to provide a compromise between cutting and quantization noise. The adverse affects of a course quantization have to be balanced between signal distortions caused by the loss of the low probability high amplitude signals.
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公开(公告)号：AT227910T
公开(公告)日：2002-11-15
申请号：AT97937939
申请日：1997-09-01
Applicant: ST MICROELECTRONICS NV
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-AKE , BENGTSSON DANIEL , HAKANSSON SIWERT , WEN YE
Abstract: PCT No. PCT/SE97/01461 Sec. 371 Date Jun. 14, 1999 Sec. 102(e) Date Jun. 14, 1999 PCT Filed Sep. 1, 1997 PCT Pub. No. WO98/10556 PCT Pub. Date Mar. 12, 1998A 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.
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公开(公告)号：DE69723563T2
公开(公告)日：2004-05-13
申请号：DE69723563
申请日：1997-09-01
Applicant: ST MICROELECTRONICS NV
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-AKE , BENGTSSON DANIEL , HAKANSSON SIWERT , WEN YE
Abstract: 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.
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公开(公告)号：DE69812850T2
公开(公告)日：2004-01-22
申请号：DE69812850
申请日：1998-02-27
Applicant: ST MICROELECTRONICS NV
Inventor： OLSSON LENNART , BAHLENBERG GUNNAR , BENGTSSON DANIEL , HAKANSSON SIWERT , ISAKSSON ANDERS , ISAKSSON LARS-AKE , ISAKSSON MIKAEL , JOHANSSON MAGNUS , LATHI MAURITZ , LJUNGGREN LIS-MARIE , LUNDBERG HANS , NORDSTROEM TOMAS , OLOFSSON SVEN-RUNE , STEFANSSON TOMAS , OEHMAN HANS , OEKVIST GOERAN
Abstract: A mechanism for achieving frame synchronization in the frequency domain. In order to synchronize a receiver with a transmitter, on signal acquisition, the interval in which orthogonality exists is determined. Once this has been achieved, an argument function is calculated from the received frame. This argument function can then be used to improve the synchronization. This system is particularly suitable for use in ADSL and VDSL modems which can be used to give broad band access over copper networks. It is also relevant to broad band transmission in mobile and semi-mobile systems for transmission over radio channels.
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公开(公告)号：DE69811716T2
公开(公告)日：2003-12-04
申请号：DE69811716
申请日：1998-11-11
Applicant: ST MICROELECTRONICS NV
Inventor： ISAKSSON MIKAEL , JOHANSSON MAGNUS , OLSSON LENNART , STEFANSSON TOMAS , OEHMAN HANS , BAHLENBERG GUNNAR , ISAKSSON ANDERS , OEKVIST GOERAN , LJUNGGREN LIS-MARIE , BENGTSSON DANIEL , OLOFSSON SVEN-RUNE , JOHANSSON JOACHIM , BOERJESSON OLA , GRIP NIKLAS , NILSSON RICHARD , SJOEBERG FRANK , WILSON SARAH , OEDLING PER
Abstract: A RFI canceller, for use in a subscriber line system using multi-carrier modulation, measures a RFI disturbance in carriers falling within a band of frequencies causing the RFI. The RFI ingress into carriers outside the band of frequencies is estimated, and an error correcting signal derived from the estimation of the RFI ingress is subtracted from a received signal. The subscriber line system may be a VDSL system and the multi-carrier modulation may be DMT. The RFI canceller includes a demodulator for demodulating an incoming data stream to provide a first parallel data stream. A parallel to serial convertor converts the first parallel data stream to a first serial data stream. A digital to analogue convertor converts the first serial data stream to a first analogue signal. An analogue RFI canceller circuit combines the analogue signal with an analogue error correcting signal, to produce a second analogue signal. An analogue to digital convertor converts the second analogue signal to a second serial data signal. A serial to parallel convertor converts the second serial data stream to a second parallel data stream. A modulator modulates the second parallel data stream onto a multiplicity of carriers.
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