WO2005013527A1 - Procede de detection du signal cdma code orthogonal - Google Patents

Procede de detection du signal cdma code orthogonal Download PDF

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Publication number
WO2005013527A1
WO2005013527A1 PCT/CN2004/000881 CN2004000881W WO2005013527A1 WO 2005013527 A1 WO2005013527 A1 WO 2005013527A1 CN 2004000881 W CN2004000881 W CN 2004000881W WO 2005013527 A1 WO2005013527 A1 WO 2005013527A1
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Prior art keywords
code
channel
interference
matched filtering
signal
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PCT/CN2004/000881
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English (en)
French (fr)
Inventor
Yingmin Wang
Guiliang Yang
Changguo Sun
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Da Tang Mobile Communications Equipment Co., Ltd.
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Application filed by Da Tang Mobile Communications Equipment Co., Ltd. filed Critical Da Tang Mobile Communications Equipment Co., Ltd.
Priority to EP04762019A priority Critical patent/EP1641161B1/en
Priority to DE200460014375 priority patent/DE602004014375D1/de
Priority to US10/562,523 priority patent/US7636384B2/en
Priority to JP2006522197A priority patent/JP4324612B2/ja
Publication of WO2005013527A1 publication Critical patent/WO2005013527A1/zh

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7097—Interference-related aspects
    • H04B1/7103—Interference-related aspects the interference being multiple access interference
    • H04B1/7105—Joint detection techniques, e.g. linear detectors
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/709—Correlator structure
    • H04B1/7093—Matched filter type
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7097—Interference-related aspects
    • H04B1/711—Interference-related aspects the interference being multi-path interference
    • H04B1/7115—Constructive combining of multi-path signals, i.e. RAKE receivers
    • H04B1/712—Weighting of fingers for combining, e.g. amplitude control or phase rotation using an inner loop

Definitions

  • Orthogonal code C band A signal detection method
  • the present invention relates to the field of mobile communication technology, and is a method for detecting a received signal applicable to an orthogonal code code division multiple access mobile communication system. Background of the invention
  • the single-user received signal detection uses a matched filtering method.
  • the matched filter performs correlation matching operations on the user's spread-spectrum sequence waveforms that pass through the channel response, and realizes the separation and detection of useful signals and interference signals.
  • multiple access interference and multipath interference the performance of the traditional single-user matched filtering method will not meet the requirements.
  • joint detection technology can be adopted, that is, the signal detection of all users and their channel response information are used to treat the signal detection as a unified and interconnected joint detection process.
  • the receiver When performing joint detection, the receiver must know the complete information of the channelization codes and channel responses of all user code channels currently accessed. In some cases, especially when the user terminal receives a downlink signal, it is often difficult to adopt a joint detection method because it is difficult to obtain this information completely.
  • the co-on and defaul t methods can meet the first condition mentioned above and can use the joint detection technology, but the specif ic method is more suitable for some large-capacity users, because in the specif ic method, each The user terminal only knows the spreading code of the user and its corresponding channel response, and cannot know the correspondence between the channel estimation code and the spreading code of other users. Therefore, in this case, it is difficult to use the information of other code channels to perform The joint detection results in a decrease in the performance of the terminal receiving detection.
  • the orthogonality of the spreading code In the 3GPP TDD system, two important pieces of information can be used: one is the orthogonality of the spreading code; the other is that the channel estimation results of all users can be obtained by the channel estimation code.
  • the spreading code is the product of the orthogonalized channelization code and the cell scrambling code. Orthogonality exists between different code channels in the same cell.
  • the complex spreading code £ is a binary number that is modulated ⁇ (w represents a rotation factor according to the chip number), and the downlink spreading code can be obtained by the following formula: Among them, is the corresponding channelization code (the spreading factor is 16, the serial number is the Walsh code) is the corresponding complex factor, and ⁇ is the complex scrambling code vector determined by the cell.
  • * T represents the conjugate transpose (same symbol H).
  • the channel response result h (k) of all users in the cell can be obtained by using the channel estimation code, which is expressed as follows:
  • k , ⁇ , K, represent different channel estimation windows
  • W represents the window length of the channel estimation
  • T represents the transpose
  • This channel response estimation result can reflect the complete channel response of one or more code channels corresponding to the channel estimation window, and can reflect the time waveform and power characteristics of the multipath response.
  • the purpose of the present invention is to provide an orthogonal code CDMA signal detection method.
  • the matched filtering method or the joint detection method can be realized in an improved and simple manner, which can reduce the The price is exchanged for the improvement of the performance of the mobile communication system.
  • An orthogonal code CDMA signal The detection method is applied to a receiving device of a time slot CDMA system using orthogonal codes, and includes the following steps:
  • An orthogonal code CDMA signal detection method is applied to a receiving device of a time slot CDMA system using orthogonal codes, and the feature is that it includes the following steps:
  • A1. Use the channel estimation code to perform channel estimation on the received signal, and obtain the channel response results of all users in the cell;
  • Judgment step B1 is to terminate this step when the joint detection is not selected, and the output is excellent.
  • the matched filtering result is the detection result of the orthogonal code CDMA signal.
  • step C1 Perform joint detection on the optimized matched filtering result obtained in step C1, and obtain a detection result that the joint detection result is an orthogonal code CDMA signal.
  • the invention provides a method for detecting an orthogonal code CDMA signal.
  • the specific implementation process may mainly include the following three steps: estimating the total power of each multipath signal; performing matched filtering on each multipath signal and using each The total power of the interference of the multipath signal is combined at the maximum ratio to obtain an optimized matched filter output; and the optimized matched filter output is jointly detected.
  • the method of the present invention uses the results of the channel estimation and the characteristics of the orthogonal code to estimate the interference to each path of the signal, and uses the estimated interference to perform maximum ratio combining.
  • the method of the present invention makes full use of the characteristics of orthogonal codes and the results of multi-user channel estimation, and realizes a matched filtering method or a joint detection method in a simple and improved manner, which can be exchanged for the improvement of the performance of the mobile communication system at a small cost.
  • the invention has important significance in the following two cases:
  • the receiver cannot obtain the complete information of the channelization code of the currently accessed interfering user code channel and its corresponding channel response, by using the method of the present invention, the information available to the receiver is fully utilized. That is, the characteristics of orthogonal codes and the result of multi-user channel estimation improve the original matched filtering and joint detection algorithms, thereby achieving improvement in system performance.
  • the optimized matched filtering method provided by the present invention is used, and its complexity is similar to the traditional matched filtering method Close, but performance has improved significantly.
  • the invention provides a solution for improving the performance of a low-complexity receiver.
  • the method of the invention is suitable for a time slot CDMA system using orthogonal codes, and is particularly suitable for the application of a terminal receiver.
  • the method of the present invention can also be adopted in a base station receiver.
  • FIG. 1 is a flowchart of a method for implementing the method of the present invention. Mode of Carrying Out the Invention
  • the method of the present invention is an orthogonal code CDMA signal detection method proposed for a time slot CDMA system using orthogonal codes, using orthogonal characteristics of spreading codes and multi-user channel response, and can be used for different conditions and requirements. Provide corresponding signal detection solutions.
  • Step 11 Use the channel estimation code to perform channel estimation on the input received signal to obtain a channel estimation result / ⁇ (Channel estimation is a step that must be performed by each mobile communication system. The method of the present invention is performed on the basis of using the channel estimation result. ).
  • Step 12 Use the result of the channel estimation to estimate the total power of each multipath signal
  • the channel estimation results can be used to estimate the total power of the interference code channel at each time delay position.
  • One of the characteristics of orthogonal codes is that the mutual interference power between different orthogonal code channels at the same delay position is zero.
  • a signal code channel is affected by the total amount of interference code channels at each delay position.
  • the interference power should be the sum of the power of the interference code channel at all delay positions, minus the interference code channel power at the same delay position as the delay position (Formula 2 below).
  • the total interference power received by the signal code channel at each time-delayed position is the interference power of the interference code channel of this cell plus the power of neighboring cells and thermal noise (Formula 3 below).
  • the interference code channel k in the formula can be taken out of participation.
  • the next step is to take the former.
  • the joint detection method will use the channel estimation result of the spreading code to jointly detect the weighted optimized matched filtering result and output the joint detection result. When the latter is adopted, only the multi-user channel estimation result and input reception will be used in the subsequent steps.
  • the signal and the estimated interference power of each multipath signal are weighted to optimize the matched filtering and output the matched filtering result.
  • the total power of the interference of each multipath signal is further estimated, that is, the sum of the total power of the signal code channel interfered with by the interference code channel and the interference of the neighboring cell and the thermal noise at each delay position are expressed as:
  • ⁇ , ⁇ is the power of the interference and thermal noise of the neighboring cell; it is the weighting factor for the interference estimation of the signal code channel interfered by the interference code channel at each delay position for formula (2), and its value range can be 0.5 To 2, this embodiment is taken as 1.
  • Step 13 By performing matched filtering on each multipath signal and performing maximum ratio combining using the interference power received by each multipath signal, an optimized matched filtering output is obtained. Use to be detected
  • the channel response estimation result of the user's spreading code at each delay position performs correlation matching filtering on each multipath signal of the signal code channel, and uses the signal code channel obtained in step 12 at each delay position
  • the total power of the interference is obtained by combining the matched filtering results of each multipath signal according to the maximum ratio and performing weighted summation to obtain an optimized matched filtering output.
  • step 12 If in step 12 the interference code channel participating in the estimation is all the code channels of the cell (that is, no joint detection is selected), this step is terminated, and the output of the optimized matched filtering result is the detection result of the orthogonal code CDMA signal, that is, the figure
  • the matched filtering result ⁇ F output from the 1 terminal is the result of detecting the orthogonal code CDMA signal; if in step 12, the interference code channel participating in the estimation is the local code channel that does not perform joint detection (that is, the joint detection is selected) To further perform step 14;
  • Step 14 Perform joint detection on the optimized matched filter output. Use the spreading code and its corresponding channel response (channel estimation result) to perform joint detection on the matched filtering result obtained in step 13.
  • the joint detection can adopt a linear processing scheme or a non-linear processing scheme.
  • the joint detection (one of the traditional joint detection methods traditionally used) can be implemented by using decision feedback and interference cancellation, or the joint detection can be implemented by a linear block equalization method.
  • ZF— BLE is a zero-forcing piece of linear equalization
  • MMSE— BLE is a piece of linear equalization for minimum mean square error
  • ⁇ réelle 2 represents the power of all interference including the interference code channel of the cell.
  • the other is a scheme that does not use joint detection.
  • This scheme only uses the steps of the optimized matching filtering (steps 12 and 13) described above, but when the interference power of each multipath signal is estimated in step 12, the interference code channel k It is the sum of all orthogonal code channels (including the user's own code channel).
  • the method of the present invention is particularly applicable to a terminal device of an orthogonal code code division multiple access system, and of course, it can also be applied to a base station device.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
  • Stereo-Broadcasting Methods (AREA)

Description

正交码 C匪 A信号检测方法
技术领域 本发明涉及移动通信技术领域， 是一种适用于正交码码分多址移动 通信***的接收信号检测方法。 发明背景
在 CDMA移动通信***中， 存在着严重的多址干扰 (MAI)和符号间干 扰（ISI)。 传统的对单用户的接收信号检测采用匹配滤波方法， 由匹配 滤波器对经过信道响应的用户的扩频序列波形进行相关匹配运算， 实现 有用信号与干扰信号的分离和检测。 在多址干扰和多径干扰严重的情况 下， 传统的单用户匹配滤波方法的性能将不能满足要求。 在时隙 C應 A ***中， 可以采用联合检测技术， 即利用所有用户的发送信号及其信道 响应的信息， 将信号检测当作一个统一的相互关联的联合检测过程来完 成。采用该联合检测方法检测接收信号，可抑制多址干扰和符号间干扰， 极大地提高码分多址***的性能 （参见 A. Klein, G. K. Kaleh and P. W. Baier, "Zero forcing and minimum mean square error equalization for multiuser detection in code division multiple access channels," IEEE Trans. Veh. Technol, vol. 45, pp.276-287, May 1996.) 。
但是， 采用联合检测方法达到改善***性能的目的是要付出代价 的， 主要有以下两方面的原因：
1 )在进行联合检测时， 接收机必须知道当前接入的所有用户码道 的信道化码及其信道响应的完整信息。 在某些情况下， 尤其是在用户终 端接收下行链路信号时， 往往因难以完整地得到这些信息而不能采用联 合检测方法。
2 )联合检测方法的计算复杂度远远高于单用户匹配滤波方法， 高 复杂度给实现带来较大的困难， 并影响到成本、 功耗和可靠性等指标。 因此， 针对不同的条件（信道环境优劣， 是否能得到完整信息等条 件）和要求（性能及实现复杂度要求等）提供相应的信号检测解决方案 就成了码分多址移动通信***应用和发展的一个重要的技术需求。
另一方面， 在 3GPP TDD标准中， 定义了三种信道估计码的分配方 式： 公共（ common )、 缺省 ( defaul t )和指定 ( specif ic )方式。 其中 的 co瞧 on和 defaul t方式因能满足上述第一条件而可以采用联合检测 技术， 但其中的 specif ic 方式， 则更适用于某些大容量用户的情况， 因为在 specif ic 方式下， 各用户终端只知道本用户的扩频码及其对应 的信道响应， 无法知道其它用户的信道估计码与扩频码之间的对应关 系， 因此， 在这种情况下难以利用其它码道的信息进行联合检测， 导致 终端接收检测的性能下降。
另外， 在某些应用中， 希望简化接收检测的算法。 一个例子是： 在 终端接收下行高速率数据的应用 （如 HSDPA: 高速下行分组接入） 中， 让终端实现复杂度较高的接收检测算法有困难； 再一个例子是： 在某些 信道环境相对较好的情况下， 就没有做联合检测的必要， 不需要采用复 杂的算法。
针对上述需求， 我们必须充分利用码分多址移动通信***的特点来 研究新的信号检测方法。
在 3GPP TDD***中， 可以利用两个重要的信息： 一个是扩频码的 正交性； 另一个是由信道估计码可以得到所有用户的信道估计结果。
关于扩频码的正交性。 在正交码码分多址***中， 扩频码是由相互 正交的信道化码与小区扰码相乘的乘积， 同一小区的不同码道之间存在 正交性。 比如， 3GPP TDD标准中复数扩频码 £ 是被 ^调制 W表示按码 片序号的旋转因子)的二进制数， 下行链路的扩频码 可由下式得到： 其中， 是对应 的信道化码（扩频因子为 16， 序号为 的沃尔 什码） 是与之对应的复数因子， Ϊ是由小区决定的复数扰码矢量。
扩频码之间存在正交性， 即满足下式：
Figure imgf000005_0001
式中 *T表示共轭转置（同符号 H ), 当扩频因子为 16时， 两个同序 号的扩频码内积结果为 16, 两个不同序号的扩频码内积结果为 0。
关于多用户的信道估计。 在 3GPP TDD***中， 利用信道估计码可 以得到本小区所有用户的信道响应结果 h(k), 表示成下式：
Figure imgf000005_0002
式中， k = ,〜,K ,代表不同的信道估计窗， W表示信道估计的窗长， T表示转置。
在 3GPP TDD标准给出的各种信道估计码分配方式中， 虽然不能保证 得到信道估计码与扩频码之间确定的对应关系， 但是可以保证得到对应 不同用户的确定的信道响应估计结果。 这个信道响应估计结果可以反映 信道估计窗口所对应的一个或多个码道的完整的信道响应， 能反映出多 径响应的时间波形和功率特性。 发明内容
本发明的目的是提供一种正交码 CDMA信号检测方法，通过充分利用 正交码的特性检测正交码 CDMA信号， 以改进的简单方式实现匹配滤波 方法或联合检测方法， 可以以较小的代价换取移动通信***性能的改 善。
实现本发明目的的技术方案可以是这样的： 一种正交码 CDMA信号 检测方法， 应用于采用正交码的时隙 CDMA ***的接收设备中， 包括步 骤：
A. 利用信道估计码对接收信号进行信道估计， 得到本小区所有用 户的信道响应估计结果， 其特征在于还包括以下步骤：
B. 选择参与估算的干扰码道， 利用本小区所有用户的信道响应估 计结果估算各个多径信号所受干扰的总功率；
C. 利用待检测用户的扩频码及其信道响应估计结果对接收信号进 行各个码道各个多径信号的匹配滤波， 并利用各个多径信号所受干扰的 总功率， 对各个多径信号的匹配滤波结果进行最大比合并， 得到优化的 匹配滤波结果， 由该优化的匹配滤波结果得到正交码 CDMA信号检测结 果。
实现本发明目的的技术方案还可以是这样的： 一种正交码 CDMA信 号检测方法， 应用于釆用正交码的时隙 CDMA ***的接收设备中， 其特 征在于包括以下步骤：
A1. 利用信道估计码对接收信号进行信道估计， 得到本小区所有用 户的信道响应结果；
B1. 利用本小区所有用户的信道响应结果， 选择不进行联合检测， 则选择本小区所有的码道作为参与估算的干扰码道， 或者选择进行联合 检测， 则选择不参与联合检测的本小区码道作为参与估算的干扰码道， 估算各个多径信号所受干扰的总功率；
C1. 利用待检测用户的扩频码及其信道响应估计结果对接收信号进 行各个码道各个多径信号的匹配滤波， 并利用各个多径信号所受干扰的 总功率， 对各个多径信号的匹配滤波结果进行最大比合并， 得到优化的 匹配滤波结果；
D1. 判断步骤 B1 中是选择不进行联合检测时终止本步驟， 输出优 化的匹配滤波结果为正交码 CDMA信号的检测结果； 判断步骤 B1中是选 择进行联合检测时， 进一步执行步骤 E1；
E1. 对步骤 C1获得的优化的匹配滤波结果进行联合检测，获得联合 检测结果为正交码 CDMA信号的检测结果。
本发明提供了一种正交码 CDMA信号的检测方法，具体的实现过程主 要可包括以下三个步驟： 估算各个多径信号所受干扰的总功率； 对各个 多径信号进行匹配滤波并利用各个多径信号所受干扰的总功率进行最 大比合并， 得到优化的匹配滤波输出； 和对优化的匹配滤波输出进行联 合检测。
可有两种实施方案： 采用优化匹配滤波检测方案时， 只需执行前两 个主要步骤； 在采用联合检测方案时， 执行全部三个主要步骤。
本发明的方法， 利用信道估计的结果和正交码的特性来估计信号每 一径所受的干扰， 并利用估计的干扰进行最大比合并。 本发明的方法充 分利用了正交码的特性和多用户信道估计的结果， 以简单的改进方式实 现了匹配滤波方法或联合检测方法， 可以以较小的代价换取移动通信系 统性能的改善。
本发明在下述两种情况下具有重要意义：
1 )在某些情况下， 接收机不能得到当前接入的干扰用户码道的信 道化码及其对应的信道响应的完整信息时， 通过采用本发明的方法， 充 分利用接收机可以得到的信息， 也即正交码的特性和多用户信道估计的 结果，改进了原有的匹配滤波和联合检测算法， 实现了***性能的改善。
2 )在某些情况下， 由于接收机实现复杂度的限制， 只能实现匹配 滤波方法， 而不能采用联合检测方法时， 利用本发明提供的优化匹配滤 波方法， 其复杂度与传统匹配滤波方法接近， 而性能却有明显的提高。 本发明为实现低复杂度接收机性能的改进提供了一种解决方案。 本发明的方法适用于采用正交码的时隙 CDMA***，尤其适用于终端 接收机的应用。 当然， 在基站接收机中也可以采用本发明的方法。 附图简要说明
图 1是实施本发明方法的流程框图。 实施本发明的方式
下面结合附图对本发明进行详细描述。
本发明的方法是针对采用正交码的时隙 CDMA ***， 利用扩频码的 正交特性和多用户的信道响应提出的一种正交码 CDMA信号的检测方法， 可针对不同的条件和要求提供相应的信号检测解决方案。
结合图 1 , 详细说明本发明方法的具体执行步骤。
步骤 11 , 利用信道估计码对输入的接收信号进行信道估计， 获得信 道估计结果/ ^ (信道估计是每一个移动通信***必须进行的步骤，本发 明方法是在利用信道估计结果的基础上进行的）。
步骤 12，利用信道估计的结果估算各个多径信号所受干扰的总功率
^ total, i °
利用信道估计的结果可以估计出干扰码道在每个时延位置上的总 功率。 正交码的特性之一是相同时延位置上的不同正交码道之间的相互 干扰功率为零， 根据该特性， 某一信号码道在每个时延位置上受到干扰 码道的总干扰功率， 应该为所有时延位置上干扰码道功率之和， 减去与 该时延位置相同的时延位置上的干扰码道功率（下述公式 2 )。信号码道 在每个时延位置上受到的总的干扰功率， 就是本小区干扰码道的干扰功 率加上邻近小区和热噪声的功率 （下述公式 3 )。
首先利用信道估计的结果 / )估算在每个时延位置上干扰码道的总 功率 Pn (符号 I仅表征干扰）:
PIJ = 公式（ 1 )
Figure imgf000009_0001
式中， w表示信道估计的窗长， k = i ",K , 代表不同的 信道估计窗， 需要注意的是： 选择进行联合检测时， 式中的 "干扰码道 k",可以取不参与联合检测的本小区码道之和；选择不进行联合检测时， 式中的 "干扰码道 k", 取包括本用户本码道的本小区所有的码道之和。 取前者时在后续步骤中将采用联合检测方法， 利用扩频码信道估计结果 对加权优化匹配滤波结果进行联合检测并输出联合检测结果； 取后者时 将在后续步驟中仅利用多用户的信道估计结果、 输入的接收信号和估算 的各个多径信号干扰功率进行加权优化匹配滤波并输出匹配滤波结果。
然后根据正交码的特性（同一时延位置上的正交码的干扰应为零）， 估算出每个时延位置（或称抽头位置， 共有 W个时延位置 )上信号码道 受到干扰码道干扰的总功率 Ii :
公式 （ 2 )
Figure imgf000009_0002
进一步估算得到各个多径信号所受干扰的总功率 ， 即每个时延 位置上信号码道受到干扰码道干扰的总功率与邻近小区干扰及热噪声 干 4尤之和， 表示成下式：
公式 （ 3 )
其中， σ,^是邻近小区干扰及热噪声的功率； 是对公式（2 )进行 每个时延位置上信号码道受到干扰码道干扰的干扰估算的加权因子， 其 取值范围可为 0.5至 2, 本实施例取为 1。
步骤 13，通过对各个多径信号进行匹配滤波并利用各个多径信号所 受的干扰功率进行最大比合并， 得到优化的匹配滤波输出。 利用待检测 用户的扩频码在每个时延位置上的信道响应估计结果对信号码道的每 个多径信号进行相关匹配滤波， 并利用步骤 12得到的信号码道在每个 时延位置上所受干扰的总功率， 对各个多径信号的匹配滤波结果按最大 比合并进行加权求和， 得到优化的匹配滤波输出。
设各个码道各个时延位置上匹配滤波后的加权系数为 , 它应该 和总的干扰功率 σ^,,,.成反比， 表示成下式： w^ oz-^- 公式（4) 由此得到优化的匹配滤波的输出为： dMF =w]Ai7'e + w2A e + -" + w A e
w
=∑w;.A;re 公式（5 )
= B*re 式中， w,. =ώ·^«),·^(2)，...,>^))®1 , 为加权系数矩阵， 0是 01½。1 积， I是单位矩阵； Α是***响应矩阵， B = w,A; , e为输入的接收信
如果在步骤 12 中， 参与估算的干扰码道是本小区所有的码道（即 选择不进行联合检测） 时终止本步驟， 输出优化的匹配滤波结果为正交 码 CDMA信号的检测结果， 即图中 1端输出的匹配滤波结果^ F就是检 测正交码 CDMA信号的结果； 如果在步骤 12中， 参与估算的干扰码道 是不进行联合检测的本小区码道（即选择进行联合检测 ) 时， 进一步执 行步骤 14;
步骤 14, 对优化的匹配滤波输出进行联合检测。 利用扩频码及其对 应的信道响应 （信道估计结果）， 对步骤 13获得的匹配滤波结果进行联 合检测。 联合检测可以采用线性处理的方案， 也可以采用非线性处理的 方案。 经联合检测后， 图中 2端得到多码道信号的联合检测输出结果即 为正交码 CDMA信号的检测结果。
可以釆用判决反馈和干扰抵消的方法实现联合检测（传统使用的联 合检测方法之一）， 或采用线性块均衡的方法实现联合检测。 其中采用 线性块均衡的联合检测算法为： ά = (Τ Β τε 公式（6 )
其中 （Τ )可通过下式求出:
Figure imgf000011_0001
式中 ZF— BLE为迫零一块线性均衡方式， MMSE— BLE为最小均 方误差一块线性均衡方式， σ„2表示包括本小区干扰码道在内的所有干扰 的功率。
综上所述， 本发明方法在实际应用时， 有两种典型的选择方案： 一种是釆用联合检测的方案。 这种方案需要完整地实现上述步骤 (步骤 12、 13、 14 )，但在步驟 12中估算各个多径信号所受干扰功率时, 干扰码道 k是取不参与联合检测的其它正交码道之和。
另一种是不采用联合检测的方案， 这种方案只釆用上述优化匹配滤 波（步驟 12、 13 ) 的步骤， 但在步骤 12中估算各个多径信号所受干扰 功率时， 干扰码道 k是取所有的正交码道（包括本用户本码道）之和。
本发明的方法尤其适用于正交码码分多址***的终端设备中， 当然 也可应用于基站设备中。

Claims

权利要求书
1. 一种正交码 CDMA信号检测方法， 应用于采用正交码的时隙 CDMA ***的接收设备中， 包括步骤：
A. 利用信道估计码对接收信号进行信道估计， 得到本小区所有用 户的信道响应估计结果， 其特征在于还包括以下步骤：
B. 选择参与估算的干扰码道， 利用本小区所有用户的信道响应估 计结果估算各个多径信号所受干扰的总功率；
C. 利用待检测用户的扩频码及其信道响应估计结果对接收信号进 行各个码道各个多径信号的匹配滤波， 并利用各个多径信号所受干扰的 总功率， 对各个多径信号的匹配滤波结果进行最大比合并， 得到优化的 匹配滤波结果， 由该优化的匹配滤波结果得到正交码 CDMA信号检测结 果。
2. 根据权利要求 1所述的方法， 其特征在于： 所述步骤 B中， 选 择参与估算的干扰码道， 是在选择不进行联合检测的条件下， 选择本小 区所有的码道作为参与估算的干扰码道； 和所述步骤 C中， 所获得的优 化的匹配滤波结果即为正交码 CDMA信号的检测结果。
3. 根据权利要求 1所述的方法， 其特征在于： 所述步骤 B中， 选 择参与估算的干扰码道， 是在选择进行联合检测的条件下， 选择不参与 联合检测的本小区码道作为参与估算的干扰码道； 和所述的步骤 C中， 由优化的匹配滤波结果得到正交码 CDMA信号检测结果， 需进一步执行 步骤 D, 包括： 对步骤 C获得的优化的匹配滤波结果进行联合检测， 获 得的联合检测结果为正交码 CDMA信号的检测结果。
4. 根据权利要求 3所述的方法， 其特征在于^述步骤 D进行联合 检测进一步包括： 采用线性块均衡的联合检测方法， 通过公式 d = (T)- 1 B*Te进行联合检测获得联合检测结果 3 , B*Te是步驟 C获得的优 化的匹配滤波结果， e 是输入的接收信号， （ T ) 通过公式
T = I A 2 ZF― BLE 求出， ^表示干扰功率。
ΒτΑ + σ,^ MMSE-BLE "
5. 根据权利要求 3所述的方法， 其特征在于所述步骤 D进行联合 检测进一步包括： 釆用判决反馈和干扰抵消的方法对步骤 C获得的优化 的匹配滤波结果进行联合检测。
6. 根据权利要求 1或 2或 3所述的方法， 其特征在于： 所述步驟 Β 中对参与估算的干扰码道， 利用本小区所有用户的信道响应估计结果估 算各个多径信号所受干扰的总功率进一步包括：
B1.利用信道响应结果/ ^通过公式 ,= ∑ A ) 2估算每个时延位
' 千扰码lA
置上干扰码道的总功率 Pu, Α = 1，.·.， 代表不同的信道估计窗；
w
Β2. 根据正交码的特性， 通过公式 /,=£；^- A.,估算出每个时延位
7=1 '
置上信号码道受到干扰码道干扰的总功率 Ii， i = l,-,W , W表示信道估 计的窗长；
B3.通过公式 ^.=风 +σ„2。进一步估算得到各个多径信号所受干扰 的总功率 σ^,,.， σ„2。是邻近小区干扰及热噪声的功率， 是对每个时延 位置上信号码道受到干扰码道干扰的干扰估算的加权因子。
7.根据权利要求 6所述的正交码 CDMA信号检测方法，其特征在于： 所述/？的取值范围为 0.5至 2。
8.根据权利要求 7所述的正交码 CDMA信号检测方法，其特征在于： 所述 的取值为 1。 '
9. 根据权利要求 1所述的正交码 CDMA信号检测方法， 其特征在于 所述步骤 C中进行最大比合并， 获得优化的匹配滤波结果进一步包括： C1. 利用各个多径信号所受干扰的总功率 σί 2。ωΛ, , 通过公式 w† oc- - 求得各个码道各个时延位置上匹配滤波后的加权系数
σΐο!αΙ,1
CI. 利用公式
Figure imgf000014_0001
得到优化的匹配滤波结果^ F ,加权系数矩阵 w,
Figure imgf000014_0002
, @是 011601^积， I是单位矩阵， A是***响应矩阵， B = W,.A,. , e为 输入的接收信号。
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006105333A1 (en) * 2005-03-31 2006-10-05 Qualcomm Incorporated Hsdpa system with reduced inter-user interference
EP1875623A2 (en) * 2005-04-27 2008-01-09 TELEFONAKTIEBOLAGET LM ERICSSON (publ) Joint detector in a code division multiple access radio receiver

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2254265A3 (en) * 2005-01-05 2013-11-27 ATC Technologies, LLC Adaptive beam forming with multi-user detection and interference reduction in satellite communication systems and methods
JP4583265B2 (ja) * 2005-07-21 2010-11-17 富士通株式会社 無線通信装置及び無線通信方法
CN101005302B (zh) * 2006-01-18 2013-02-13 上海原动力通信科技有限公司 时隙码分多址***进行干扰抑制的下行波束赋形方法
JP5046317B2 (ja) * 2006-04-27 2012-10-10 住友電気工業株式会社 受信機、送信機、伝送システム、及び伝送方法
US20120122415A1 (en) * 2009-07-29 2012-05-17 Nec Casio Mobile Communications, Ltd. Wireless communication device and signal detecting method
CN101986744B (zh) * 2009-07-29 2013-03-20 中兴通讯股份有限公司 一种长期演进***中信号检测的方法及装置
CN102013902B (zh) * 2009-11-11 2014-07-23 电信科学技术研究院 一种小区间干扰抑制方法和通信设备
KR101694985B1 (ko) * 2010-01-22 2017-01-12 인하대학교 산학협력단 부분공간 간섭 정렬 방법 및 간섭 정렬 시스템
EP2578061B1 (en) 2010-06-02 2015-02-25 Koninklijke Philips N.V. Method for controlling a lighting system, and lighting system
US8489031B2 (en) * 2011-05-18 2013-07-16 ReVerb Networks, Inc. Interferer detection and interference reduction for a wireless communications network
US9490867B2 (en) 2011-08-16 2016-11-08 Harris Corporation CDMA communications device and related methods
CN103532608B (zh) * 2012-07-03 2018-01-19 中兴通讯股份有限公司 多用户联合检测的方法及装置

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11251965A (ja) * 1998-03-05 1999-09-17 Fujitsu Ltd マッチドフィルタ及びｃｄｍａ通信方式の無線受信装置
CN1355627A (zh) * 2000-11-27 2002-06-26 华为技术有限公司 基于码分多址***的多址干扰抑制方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6865218B1 (en) * 2000-11-27 2005-03-08 Ericsson Inc. Multipath interference reduction for a CDMA system
JP3345406B1 (ja) 2001-05-25 2002-11-18 松下電器産業株式会社 無線受信装置及び無線受信方法

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11251965A (ja) * 1998-03-05 1999-09-17 Fujitsu Ltd マッチドフィルタ及びｃｄｍａ通信方式の無線受信装置
CN1355627A (zh) * 2000-11-27 2002-06-26 华为技术有限公司 基于码分多址***的多址干扰抑制方法

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006105333A1 (en) * 2005-03-31 2006-10-05 Qualcomm Incorporated Hsdpa system with reduced inter-user interference
EP2262150A1 (en) * 2005-03-31 2010-12-15 Qualcomm Incorporated HSDPA system with reduced inter-user interference
US7889755B2 (en) 2005-03-31 2011-02-15 Qualcomm Incorporated HSDPA system with reduced inter-user interference
US8634433B2 (en) 2005-03-31 2014-01-21 Qualcomm, Incorporated HSDPA system with reduced inter-user interference
EP1875623A2 (en) * 2005-04-27 2008-01-09 TELEFONAKTIEBOLAGET LM ERICSSON (publ) Joint detector in a code division multiple access radio receiver
EP1875623A4 (en) * 2005-04-27 2012-09-12 Ericsson Telefon Ab L M COMPOUND DETECTOR IN A CDMA RADIO RECEIVER

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