公开(公告)号：WO2009060023A3

公开(公告)日：2009-05-14

申请号：PCT/EP2008/065045

申请日：2008-11-06

Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL) ,  LINDOFF, Bengt ,  NILSSON, Johan ,  WILHELMSSON, Leif ,  NORDSTRÖM, Fredrik

Inventor： LINDOFF, Bengt ,  NILSSON, Johan ,  WILHELMSSON, Leif ,  NORDSTRÖM, Fredrik

IPC: H04B7/08 ,  H04L25/02

Abstract: A multi-branch OFDM receiver combines diversity signals received over different receiver branches using interference rejection combining. The receiver generates first channel estimates associated with a serving base station, second channel estimates associated with at least one non-serving base station, and a time offset between the serving base station and non-serving base station. The receiver computes a noise covariance matrix based on the second channel estimates and the time offset, and then combines the diversity signals received over different branches using the first channel estimates and the noise covariance matrix.

公开(公告)号：WO2009037110A1

公开(公告)日：2009-03-26

申请号：PCT/EP2008/061612

申请日：2008-09-03

Applicant: TELEFONAKTIEBOLAGET LM ERICSSON (publ) ,  WILHELMSSON, Leif ,  REIAL, Andres

Inventor： WILHELMSSON, Leif ,  REIAL, Andres

IPC: H04L1/00 ,  H04L1/06

CPC classification number: H04L1/0006 ,  H04L1/0009 ,  H04L1/0018 ,  H04L1/0045 ,  H04L1/0084 ,  H04L1/06

Abstract: The teachings presented herein provide methods and apparatus for use in a multiple-input multiple-output (MIMO) system transmitting a plurality of data substreams to a receiver employing ordered successive interference cancellation detection according to a predetermined sequence for decoding the data substreams. In an exemplary method, a quality of service (QoS) requirement is determined for each of two or more application-specific data streams, and the application-specific data streams are assigned to the data substreams according to the determined QoS requirements and the predetermined sequence, so that application-specific data streams having more stringent QoS requirements are decoded earlier than application-specific data streams having less stringent QoS requirements. In some embodiments, the determined QoS requirements comprise maximum delay requirements, and application-specific data streams requiring shorter maximum delays are assigned to earlier-decoded data substreams than application-specific data streams having less stringent maximum delay requirements. In other embodiments, the determined QoS requirements comprise an application-specific robustness, wherein application-specific data streams corresponding to less robust applications are assigned to earlier-decoded data substreams than application-specific data streams corresponding to more robust applications.

Abstract translation: 本文提出的教导提供了用于在多输入多输出（MIMO）系统中使用的方法和装置，该多输入多输出（MIMO）系统根据用于解码数据子流的预定顺序将有序的连续干扰消除检测发送到接收机。 在一个示例性方法中，针对两个或多个应用特定数据流中的每一个确定服务质量（QoS）要求，并且根据所确定的QoS要求和预定顺序将应用专用数据流分配给数据子流 ，使得具有更严格的QoS要求的特定于应用的数据流比具有较不严格的QoS要求的特定于应用的数据流更早地解码。 在一些实施例中，所确定的QoS要求包括最大延迟要求，并且需要较短最大延迟的应用专用数据流被分配给早期解码的数据子流，而不是具有较不严格的最大延迟要求的特定于应用的数据流。 在其他实施例中，所确定的QoS要求包括特定于应用的鲁棒性，其中对应于较不健壮的应用的特定应用的数据流被分配给比较强健应用的应用特定数据流更早解码的数据子流。

公开(公告)号：WO2008049713A1

公开(公告)日：2008-05-02

申请号：PCT/EP2007/060465

申请日：2007-10-02

Applicant: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) ,  LINDOFF, Bengt ,  WILHELMSSON, Leif

Inventor： LINDOFF, Bengt ,  WILHELMSSON, Leif

IPC: H04L27/26 ,  H04Q7/38 ,  H04L12/28

CPC classification number: H04L27/2647 ,  H04J11/0069 ,  H04L27/2613

Abstract: Ascertaining which one of a number of cells of a cellular communication system transmitted an OFDM signal involves obtaining reference symbols from the OFDM signal. Compensating phase shift values for phase aligning the plurality of reference symbols are estimated and used to generate phase corrected reference symbols. At least two scrambling code sequences are applied to the phase corrected reference symbols to obtain at least two de-scrambled phase corrected reference symbol sequences, wherein each of the scrambling codes is associated with a respectively different one of the cells of the cellular communication system. A power value of each of the de-scrambled phase corrected reference symbol sequences is ascertained. That one of the scrambling codes that is associated with a highest one of the power values is ascertained, thereby ascertaining which one of the number of cells of the cellular communication system transmitted the OFDM signal.

Abstract translation: 确定传输OFDM信号的蜂窝通信系统的多个小区中的哪个小区涉及从OFDM信号获得参考符号。 用于相位对准多个参考符号的补偿相移值被估计并用于产生相位校正的参考符号。 至少两个扰码序列被施加到相位校正的参考符号以获得至少两个去加扰相位校正的参考符号序列，其中每个扰码与蜂窝通信系统的分别不同的一个小区相关联。 确定每个解扰相位校正参考符号序列的功率值。 确定与功率值中最高功率值相关联的扰码中的一个，从而确定蜂窝通信系统的小区数目中的哪一个发送OFDM信号。

公开(公告)号：WO2007068407A1

公开(公告)日：2007-06-21

申请号：PCT/EP2006/011838

申请日：2006-12-08

Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL) ,  WALLEN, Anders ,  WILHELMSSON, Leif

Inventor： WALLEN, Anders ,  WILHELMSSON, Leif

IPC: H04L27/227 ,  H04L27/233 ,  H04L27/00

CPC classification number: H04L27/2271 ,  H04L27/2331 ,  H04L2027/0067 ,  H04L2027/0069

Abstract: A method and apparatus for compensation of noise in a received signal includes receiving a received signal comprised of a sum of a transmitted signal and a disturbance signal in a demodulator, summing the received signal and a compensation signal to produce a demodulation signal, determining a transmitted symbol based upon the demodulation signal, determining an error signal by calculating a difference between the demodulation signal and the determined transmitted symbol, and determining the compensation signal from the error signal using a model-based disturbance suppression control process. In at least one embodiment, the model-based disturbance suppression control process is a linear disturbance model control process.

Abstract translation: 用于补偿接收信号中的噪声的方法和装置包括在解调器中接收由发射信号和干扰信号之和组成的接收信号，对接收信号和补偿信号求和以产生解调信号， 基于解调信号的符号，通过计算解调信号和确定的发送符号之间的差来确定误差信号，以及使用基于模型的干扰抑制控制处理从误差信号确定补偿信号。 在至少一个实施例中，基于模型的干扰抑制控制过程是线性干扰模型控制过程。

公开(公告)号：WO2007048585A1

公开(公告)日：2007-05-03

申请号：PCT/EP2006/010264

申请日：2006-10-25

Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL) ,  WILHELMSSON, Leif ,  BERNHARDSSON, Bo ,  LARSSON, Per-Ola

Inventor： WILHELMSSON, Leif ,  BERNHARDSSON, Bo ,  LARSSON, Per-Ola

IPC: H04L25/02

CPC classification number: H04L25/023 ,  H04L25/0204 ,  H04L25/022 ,  H04L27/2608 ,  H04L27/2647

Abstract: A method and apparatus for predicting channel estimates for non-received signal frequencies provides knowledge of propagation channel characteristics for non-received frequencies. One embodiment predicts uplink (or downlink) channel estimates based on measured downlink (or uplink) channel estimates, which is advantageous in systems having different uplink and downlink frequencies. Another embodiment predicts channel responses for non-received OFDM sub carrier frequencies based on measuring channel responses for received OFDM sub carrier frequencies. Such processing may comprise, for example, measuring channel responses for received OFDM pilot sub carriers, predicting channel responses at frequency intervals corresponding to pilot sub carrier spacing, and interpolating between those values to predict channel responses at data sub carrier frequencies. The prediction of the channel frequency responses for non-received signal frequencies is done using an autoregression model.

Abstract translation: 用于预测未接收信号频率的信道估计的方法和装置提供了对于未接收频率的传播信道特性的知识。 一个实施例基于测量的下行链路（或上行链路）信道估计来预测上行链路（或下行链路）信道估计，这在具有不同的上行链路和下行链路频率的系统中是有利的。 另一个实施例基于对接收的OFDM子载波频率的测量信道响应来预测未接收的OFDM子载波频率的信道响应。 这样的处理可以包括例如测量接收的OFDM导频子载波的信道响应，以对应于导频子载波间隔的频率间隔预测信道响应，以及在这些值之间内插以预测数据子载波频率处的信道响应。 非接收信号频率的信道频率响应的预测使用自回归模型进行。

公开(公告)号：WO2006131250A1

公开(公告)日：2006-12-14

申请号：PCT/EP2006/005190

申请日：2006-05-31

Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL) ,  WILHELMSSON, Leif

Inventor： WILHELMSSON, Leif

IPC: H04B7/005 ,  H04L27/26

CPC classification number: H04W52/42 ,  H04B7/01 ,  H04L5/0007 ,  H04L5/0037 ,  H04L5/0044 ,  H04L5/006 ,  H04L5/0062 ,  H04L5/0066 ,  H04L5/0085 ,  H04L5/0096 ,  H04L27/2657 ,  H04W52/282 ,  H04W52/346

Abstract: Digital data Symbols from a transceiver are transmitted to at least two remote transceivers in a wireless Communications System employing Orthogonal Frequency Division Multiplexing, wherein a number of available sub-carriers are shared between said remote transceivers. Information about magnitudes of Doppler effect experienced by the remote transceivers is provided; sub-carriers are allocated to each remote transceiver in dependence of the information about magnitudes of Doppler effect; and a power level transmitted to each of said remote transceivers is controlled in dependence of the Information about magnitudes of Doppler effect. In this way the reception of OFDM Signals for transceivers moving at high speed and thus experiencing a high Doppler effect is improved without degrading the reception quality for transceivers with low or no Doppler effect. Thus the Performance of a System based on OFDM and multiple access is improved.

Abstract translation: 数字数据来自收发器的符号在采用正交频分复用的无线通信系统中的至少两个远程收发机传输，其中在所述远程收发器之间共享多个可用子载波。 提供有关远程收发器所经历的多普勒效应的大小的信息; 根据关于多普勒效应的大小的信息，将子载波分配给每个远程收发器; 并且根据关于多普勒效应的幅度的信息来控制发送到每个所述远程收发器的功率电平。 以这种方式，改善了用于收发机高速移动并因此经历高多普勒效应的OFDM信号的接收，而不降低具有低或无多普勒效应的收发器的接收质量。 因此，提高了基于OFDM和多路访问的系统的性能。

公开(公告)号：WO2006111276A1

公开(公告)日：2006-10-26

申请号：PCT/EP2006/003174

申请日：2006-04-07

Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (publ) ,  SVENSSON, Jim ,  WILHELMSSON, Leif

Inventor： SVENSSON, Jim ,  WILHELMSSON, Leif

IPC: H04L25/02 ,  H04L27/26

CPC classification number: H04L25/0232 ,  H04L25/0216 ,  H04L25/022 ,  H04L25/0234 ,  H04L27/2647 ,  H04L27/2665

Abstract: A channel response estimate is generated from a received signal that comprises two or more different pilot carriers in an Orthogonal Frequency Division Multiplexing (OFDM) communications system. This involves, for each of the carriers, determining a rotation amount that is at least in part a function of a frequency separation between two adjacent carriers, a delay spread of the channel, and a position of the carrier relative to other carriers within the received signal. The received signal is processed with a Fast Fourier Transform, thereby generating a processed signal. Prior to performing frequency interpolation as part of a channel estimation process, the processed signal is rotated by the rotation amount. The channel response is estimated by performing the channel estimation process at least in part on the rotated processed signal.

Abstract translation: 从正交频分复用（OFDM）通信系统中的包含两个或多个不同导频载波的接收信号产生信道响应估计。 这涉及对于每个载波，确定至少部分地是两个相邻载波之间的频率间隔的函数的旋转量，信道的延迟扩展以及载波相对于所接收的载波内的其他载波的位置 信号。 接收到的信号用快速傅里叶变换处理，从而产生处理后的信号。 在作为信道估计处理的一部分进行频率插值之前，处理后的信号旋转旋转量。 通过至少部分地基于经旋转处理的信号执行信道估计处理来估计信道响应。

公开(公告)号：WO2005048546A3

公开(公告)日：2005-05-26

申请号：PCT/EP2004/012797

申请日：2004-11-11

Applicant: TELEFONAKTIEBOLAGET LM ERICSSON (publ) ,  WILHELMSSON, Leif ,  ANDERSSON, Lennart ,  BERNHARDSSON, Bo

Inventor： WILHELMSSON, Leif ,  ANDERSSON, Lennart ,  BERNHARDSSON, Bo

IPC: H04L25/02

Abstract: Methods and apparatus that achieve good channel estimation without using unnecessarily complex interpolation filters are described. Adaptive interpolation filtering of a signal in a receiver includes determining at least one correlation function parameter of the channel and determining a filter configuration based on the correlation function parameter. The interpolation may be performed in time, where a Doppler frequency shift can serve as the correlation function parameter, or in frequency, where a root mean square or maximum delay spread can serve as the correlation function parameter, or both. A worst case signal-to-noise ratio may be used in determining the filter configuration, or, optionally, the signal-to-noise ratio can be determined in real time. The filter configuration can be determined in real time or selected from one of a plurality of predetermined configurations having different complexities.

公开(公告)号：WO2003075528A1

公开(公告)日：2003-09-12

申请号：PCT/EP2003/001945

申请日：2003-02-26

Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (publ) ,  WILHELMSSON, Leif ,  MALM, Peter

Inventor： WILHELMSSON, Leif ,  MALM, Peter

IPC: H04L27/34

CPC classification number: H04L27/38 ,  H04L25/067

Abstract: A sub-optimal method is disclosed for calculating the reliability values (soft values) for the bits of a multilevel signal. The log-likelihood values are approximated using only the dominant terms, so called max-log approximation, that is for each bit position only the two closest signal symbols of opposite bit value (S 8 ,S 6 ) are considered in the sum. The used modulation scheme is 16-QAM together with Gray-labelling. Two versions of approximation are proposed: one version consists of using the two distances between the received value and the two closest symbols of opposite bit value ( δ 1 , δ 2 ). In order to simplify and speed up the calculation, the second version consists of using the distance between the two closest symbols (δ 3 ) to approximate the distance between the second closest symbol and the received value. Furthermore, precalculated results are stored in look-up tables to speed up the calculation. Possible applications are especially bit interleaved coded modulation (BICM) together with soft-input decoding. It is also of interest for TCM and BCM schemes.

Abstract translation: 公开了一种用于计算多电平信号的位的可靠性值（软值）的次优方法。 对数似然值仅使用主要术语近似，所谓的最大对数近似，即对于每个比特位置，只有相反比特值（S8，S6）的两个最接近的信号符号被考虑在和中。 所使用的调制方案是16-QAM和Gray标签。 提出了两个近似版本：一个版本包括使用接收值和相对位值的两个最接近的符号（delta1，delta2）之间的两个距离。 为了简化和加速计算，第二个版本包括使用两个最接近的符号（delta3）之间的距离近似第二个最接近的符号与接收的值之间的距离。 此外，预先计算的结果存储在查找表中以加快计算。 可能的应用是软交织编码调制（BICM）以及软输入解码。 也是TCM和BCM方案的兴趣。

公开(公告)号：WO02078195A2

公开(公告)日：2002-10-03

申请号：PCT/EP0202777

申请日：2002-03-12

Applicant: ERICSSON TELEFON AB L M ,  WILHELMSSON LEIF

Inventor： WILHELMSSON LEIF

IPC: H03M13/05 ,  H03M13/27 ,  H03M13/37

CPC classification number: H03M13/2707 ,  H03M13/05 ,  H03M13/37

Abstract: Method and apparatus (30) for decoding block-coded data which has been transmitted by means of differential modulation. The method first attempts to decode all codewords using an error correcting code (100), and if at least one codeword is still not decoded, uses a correctly decoded codeword to locate a possibly erroneous code symbol in the at least one codeword, alters the possibly erroneous code symbol (120), and again attempts to decode the at least one codeword (130). The invention recognizes that errors in such data typically occur in pairs, and utilizes this property to improve the decoding process.

Abstract translation: 用于解码通过差分调制发送的块编码数据的方法和装置（30）。 该方法首先尝试使用纠错码（100）解码所有码字，并且如果至少一个码字仍未解码，则使用正确解码的码字来定位至少一个码字中的可能错误的码符号，改变可能的 错误代码符号（120），并再次尝试对至少一个码字（130）进行解码。 本发明认识到这种数据中的错误通常成对出现，并且利用该属性来改进解码过程。