TW583851B - Fast converging affine projection based echo canceller for sparse multi-path channels - Google Patents
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583851 A7 B7 五、發明説明( 相關申請 此項申請主張於2000年9月8曰申請之美國暫時性申請 號碼60/231,419的利益(代理人文件號碼004419.P016Z) 背景 1 .領域 本發明與信號處理有關。特別是,本發明與回音消除 關。 *、 2 ·相關技藝說明 在電話技術中通常回音是不想要的。回音是由許多來源 所引起的。這些包含自喇叭回到麥克風的信號之多重反 射’在喇叭和麥克風間的音波耦合,以及周圍的澡音。回 骨消除是一種消除銃想要的回音效應之技術。此回音消^ 器估計此回音路徑的脈衝響應且產生一此回音之估計。此 估計的回音接著自此近-端信號被減掉。典型地,一適應 性濾波器被用以估計此回音因為此回音路徑通常是未知的 且隨機地隨時間而變。 一用於回音消除器的技術是正規化最小均方(nlms)方 法。此技術試著最小化此平方誤差的期望值。盔 此正規化最小均方方法有許多缺點。—重要的缺對 於色彩輸入的低收斂速率。而且,當此回音通道具有稀疏 的多路徑通道時,此正規化最小均方方法可能不能提供適U 當的結果。 因此,有一對具有在稀疏的多路徑通道中執行回音消除 的收斂速率比此正規化最小均方方法更快之有效技術的需 -4- 本纸張尺度適用中國國家標準(CNS) Α4規格(21〇χ297公釐) 裝 訂 583851 A7 B7 求0 星A之簡要說明 經由以下本發明的詳細說明,本發明的特色和優點會變 得更加顯著: 圖1是一圖示本發明的.一實施例可在其上實施的系統之 圖形。 圖2是一圖示根據本發明的一實施例,在圖丨中所示的 用於此基於仿射投影的回音消除器之系統模型圖形。 圖3是一圖示根據本發明的一實施例,在圖丨中所示的 一基於仿射投影的回音消除器之圖形。 圖4A是一圖示根據本發明的一實施例,在圖3中所示的 一用於基於仿射投影的回音消除器之適應性滤波器的圖 形。 圖4B是一圖示此根據本發明的一實施例,在圖3中所示 的一用於基於仿射投影的回音消除器之適應性濾波器的圖 形。 圖5是一圖示此根據本發明的一實施例,在圖2中所示 的一用於基於仿射投影的回音消除器之延遲估計器的圖 形。 圖6是一圖示一根據本發明的一實施例,用於一回音消 除器之處理的流程圖。 圖7是一圖示一根據本發明的一實施例,用於在圖6中 所示使用仿射投影更新的適應性濾波之處理的流程圖。 圖8是一圖示一根據本發明的一實施例,用於在圖6中 本紙張尺度適用中國國家標準(CNS) A4規格(210 X 297公釐) " " 1 ----583851 A7 B7 V. Description of the Invention (Related Application This application claims the benefit of US Provisional Application No. 60 / 231,419, filed on September 8, 2000 (Agent Document No. 004419.P016Z) Background 1. Fields of the invention and signals Processing is concerned. In particular, the present invention is related to echo cancellation. *, 2 · Relevant technical description. In telephone technology, echo is usually unwanted. Echo is caused by many sources. These include the signal from the speaker back to the microphone. Multiple reflections' sonic coupling between the horn and microphone, as well as the surrounding bathing sound. Echobone cancellation is a technique to eliminate the desired echo effect. This echo canceller estimates the impulse response of this echo path and generates an echo The estimated echo is then subtracted from the near-end signal. Typically, an adaptive filter is used to estimate the echo because the echo path is usually unknown and changes randomly over time. The technique for echo cancellers is the normalized least mean square (nlms) method. This technique tries to minimize the expected value of this squared error. This normalization The small mean square method has many disadvantages.—The important one is the low convergence rate for color input. Moreover, when this echo channel has sparse multipath channels, this normalized minimum mean square method may not provide appropriate U results. Therefore, there is a need for a pair of effective techniques that perform an echo cancellation in a sparse multipath channel with a faster convergence rate than this normalized least-mean-square method. -4- This paper standard applies the Chinese National Standard (CNS) Α4 specification ( 21〇χ297mm) Binding 583851 A7 B7 Find 0 A brief description of the star A Through the following detailed description of the present invention, the features and advantages of the present invention will become more significant: Figure 1 is a diagram illustrating the present invention. An embodiment A diagram of a system that can be implemented on it. Fig. 2 is a diagram illustrating a system model for the affine projection-based echo canceller shown in Fig. 丨 according to an embodiment of the present invention. Fig. 3 is A diagram illustrating an echo canceler based on affine projection shown in FIG. 丨 according to an embodiment of the present invention. FIG. 4A is a diagram illustrating an embodiment according to the present invention, shown in FIG. 3 A diagram of an adaptive filter for an echo canceller based on affine projection. Fig. 4B is a diagram illustrating an example of an affine projection based on affine projection according to an embodiment of the present invention. Figure of an adaptive filter of an echo canceller. Fig. 5 is a diagram illustrating a delay estimator for an echo canceller based on affine projection shown in Fig. 2 according to an embodiment of the present invention. FIG. 6 is a flowchart illustrating a process for an echo canceller according to an embodiment of the present invention. FIG. 7 is a diagram illustrating an embodiment according to the present invention for use in FIG. 6. FIG. 8 is a flowchart illustrating a process of adaptive filtering updated using an affine projection. FIG. 8 is a diagram illustrating an embodiment according to the present invention for applying the Chinese National Standard (CNS) A4 specification to the paper size in FIG. 6 ( 210 X 297 mm) " " 1 ----
裝 B7B7
所不之延遲估計之處理的流程圖。 旦圖9是一圖示根據本發明的一實施例,用於使用仿射投 〜更新的部分適應性濾波之處理的流程圖。 圖10A是一圖示根據本發明的一實施例,在此第一適應 陵Ρέϊ叙之後用於非·稀疏通道的權值之圖形。 圖1 0Β是一圖示根據本發明的一實施例,用於非·稀疏 通道之前一萬個學習取樣的均方誤差(MS Ε)之圖形。 、圖10C是一圖示根據本發明的一實施例,甩於非-稀疏 通道之一萬個取樣之後的此通道脈衝響應之估計的圖形。 圖11A是一圖示根據本發明的一實施例,在此第一適應 性階段之後用於稀疏通道的權值之圖形。 、是-圖示根據本發明的一實施例,用於稀疏通道 又則一萬個學習取樣的均方誤差(M s Ε )之圖形。A flowchart of the processing of the delay estimation. FIG. 9 is a flowchart illustrating a process for partially adaptive filtering using affine casting to update according to an embodiment of the present invention. FIG. 10A is a graph illustrating weights for non-sparse channels after the first adaptation process according to an embodiment of the present invention. FIG. 10B is a graph illustrating the mean square error (MS E) of the 10,000 learning samples before the non-sparse channel according to an embodiment of the present invention. FIG. 10C is a graph illustrating an impulse response estimation of a non-sparse channel after 10,000 samples of the channel according to an embodiment of the present invention. Fig. 11A is a graph illustrating weights for sparse channels after this first adaptive phase according to an embodiment of the present invention. Yes, illustrates a graph of the mean square error (M s Ε) for a sparse channel and then 10,000 learning samples according to an embodiment of the present invention.
圖lie是一圖示根據本發明·的一實施例,用於非-稀疏 通道之-萬個取樣之後的此通道脈衝響應之估計的圖形。U 在以下的說明中,為了解釋的目的,說明許多以 提供對本發明的完整了無論如何,這些特定細節的某 些可能不須要用以實施本發明。在並, 仗丹匕的例子中,為人孰 知的電氣結構和電路是以方塊圖的开J - B0 M 7 %式顯不以免模糊本發 本發明可以硬體,軟體,軔 合來具體實現。當以軟體,軔 本發明的元素是程式碼或用以 體,微碼,或這些的任意組 體,或微碼來具體實現時, 執行必需工作之碼區段。一 -6 - 本紙張尺度適用中國國家標準(CNS) A4規格(210X 297公釐)—'' --— 碼區段”可以代表一程序,一函數,一子程式,一程式,一 2式,一次常式,一模組,一軟體包裝,一類別或任何指 令,資料結構的組合,或程式敘述。一碼區段可藉由傳送 和/或接收資訊,資料,引數,參數,或記憶體内容,被耦 口到另一程式區段或一硬體電路。資訊,引數,參數,資 料等可藉由包含記憶體分享,訊息傳送,權杖傳送,網路 傳輸,等 <裝置,被傳送,前送,或傳輸。此程式或碼區段 可儲存於一處理器可讀之媒體中或藉由一實施於一載波中 的電腦資料或一為載波所調變之信號在一傳輸媒體上被傳 輸此處理器可讀之媒體”可包含任何可儲存或傳送資 訊的媒體。此處理器可讀之媒體的實例包含一電子電路,、 半導體記憶裝置,唯讀記憶體(R0M),快閃記憶體,可抹 除唯謂記憶體(EROM),軟碟,唯讀光碟(CD-R〇M),光 碟,硬碟,光纖媒體,射頻(RF)鏈結,等等。此電腦資料信 號可包含任何可在一如電子網路通道,光纖,無線電,^ 磁,射頻鏈結等的傳輸媒體上傳播的信號。這些碼區段^ 藉由如網際網路,企業内部網路的電腦網路來下載。 >王意本發明可被說明成通常被敘述成流程圖,流程圖 形,結構圖,或方塊圖的一處理。雖然一流程圖可將這些 操作描述成一串列處理,但許多的這些操作可以平行或= 時的方式來執行。此外,這些操作的次序可重新安排。當 其操作完成時,一處理被終止。一處理可被對應到一方 法,函數,程序,次常式,次程式等。一處理對應到一函數 時,其終止對應到此函數的回歸到呼叫的函數或主函Figure lie is a graph illustrating an estimate of the impulse response of a non-sparse channel for this channel after 10,000 samples according to an embodiment of the present invention. U In the following description, for the purpose of explanation, many are provided to provide completeness of the invention. However, some of these specific details may not be required to implement the invention. In the example of the dagger, the known electrical structure and circuit are shown in the block diagram of J-B0 M 7%, so as not to obscure the present invention. The present invention can be specified in hardware, software, or combination. achieve. When implemented in software, the elements of the present invention are code, or body, microcode, or any combination of these, or microcode, to implement the necessary code segments. 1-6-This paper size is in accordance with Chinese National Standard (CNS) A4 specification (210X 297 mm) — "--code section" can represent a program, a function, a subprogram, a program, a 2 formula , A routine, a module, a software package, a category or any instruction, a combination of data structures, or a program description. A code segment can send and / or receive information, data, arguments, parameters, or Memory content is coupled to another program section or a hardware circuit. Information, arguments, parameters, data, etc. can be included through memory sharing, message transmission, token transmission, network transmission, etc. < The device is transmitted, forwarded, or transmitted. This program or code segment can be stored in a processor-readable medium or by a computer data implemented on a carrier wave or a signal modulated by the carrier wave. "Transmission-readable media on a transmission medium" may include any medium that can store or transmit information. Examples of media readable by the processor include an electronic circuit, a semiconductor memory device, a read-only memory (ROM), a flash memory, and an erasable only memory (EROM), a floppy disk, and a read-only optical disk ( CD-ROM), optical discs, hard drives, fiber optic media, radio frequency (RF) links, and more. The computer data signal may include any signal that can be transmitted on a transmission medium such as an electronic network channel, optical fiber, radio, magnetic field, radio frequency link, and the like. These code segments ^ are downloaded via computer networks such as the Internet, corporate intranets. > Wangyi The present invention can be described as a process which is generally described as a flowchart, a flowchart, a structure diagram, or a block diagram. Although a flowchart can describe these operations as a series of processes, many of these operations can be performed in parallel or = time. In addition, the order of these operations can be rearranged. When its operation is completed, a process is terminated. A process can be mapped to a method, function, program, subroutine, subprogram, etc. When a process corresponds to a function, it terminates the function or main function corresponding to the return to call of this function
、發明説明( 網路145,一送出輸入解碼器 送出輸出編碼器180,一接收輸 圖1是一圖示本發明的 之圖形。此系統實=可在其上實施的系統- 遒12〇,~送出輸出編;器碼器U°,—回音通 —接收輸出編碼器15〇, —接收輸入解碼Suo · 160,一回音通道170… 入解碼器190,头一 r 〜…侧W、漏兩 和一接收輸出編碼器195。 运出輸入解碼器1 1〇接 户 且將此編碼語音解碼成娃 來自弟一近端的編碼語音 中,此逆㈣性語音資料Sin。在-實施例 此回立,甬 解碼器110是-卜法則/A-法則解碼器。 二運120包含-使用仿射投影(AP)之回音消除器 立次。、此基於仿射投影(Ap)之回音消除器125自此線性語 曰貝料取樣Sin移除-回音估計信號以產生線性資料取樣 S〇Ut二此送出輸出編碼器13G提供了封包前的語音壓縮。 在見施例中,此送出輸出編碼器130是一使用包含國際 二,聯盟(ITU)-T國際標準化G 7xx系列之用於低_位元速 率聲音(LBRV)的任一壓縮標準以壓縮來自此回音通道12〇 之居音資料Sout的G.7xx編碼器。此壓縮過之語音資料經 由一網路被送到遠端。接收輸入解碼器14〇解壓縮接收在 網路145上來自此第一遠端的語音資料。此解壓縮技術與 使用於送出輸出編碼器上的壓縮技術是相容的。回音 通道120接收來自接收輸入解碼器14〇的Rin且送出Rout線 性資料取樣。接收輸出編碼器150將線性資料取樣Rout編 碼成預備送出到此第一近端的;z -法則和A -法則編碼語 音。 -8- *^[^度適用中§國家標準(CNS) A4規格(210 X 297公釐) 裝 訂 € 五、發明説明(6 ) 於出編碼IM30能力傳送或封包化資料自和到此送出 1和接^ ㈣收輸入解碼器 ,和接收輸出解碼器195上的任何網路。此網路145可 以是網際網路,—企業内部網路,一外部網路,一區域網 路(LAN),或一廣域網路(WAN)。送出輸入解碼器⑽接 收=自罔路145的編碼語首且將此編碼語音解碼成線性語 晋’貝料Sm。在一實施例中,送出輸入解碼器⑽是一’ 法則法則解碼器。回音通道17〇包含一使用仿射投影 間之回音消除器175。此基於仿射投影之回音消除器 175自此線性語晋資料取樣^移除—回音估計信號以產生 線性資料取樣S〇ut。送出輸出編碼器18〇提供了封包化前 的語音壓縮。纟-實施例中,此送出輸出編碼器刚是一 使用包含國際電信聯盟(ITU)_T國際標準化g 系列之用 於低-位元速率聲音(LBRV)的任一壓縮標準以壓縮來自回 音通道170之語音資料S〇ut的G.7xx編碼器。此壓縮過之語 音資料被送到在第:遠端之—接收裝置。接收輸人解碼器 190解錢接收自此第二遠端的語音資料。此解壓縮技術 與使用於送出輸出編碼器18〇上的壓縮技術是相容的。回 音通道170接收來自接收輸入解碼器19〇的尺化且送出此Description of the invention (Network 145, one sending input decoder sending output encoder 180, one receiving input Figure 1 is a diagram illustrating the invention. This system is actually a system that can be implemented on it-遒 12〇, ~ Send output code; encoder U °, —echo pass—receive output encoder 15〇, —receive input decode Suo · 160, one echo channel 170… enter decoder 190, the first one is r ~ ... the side is W, two are missing And a receiving output encoder 195. Take out the input decoder 1 110 to receive the user and decode this encoded speech into a near-end encoded speech from the younger brother, this inverse speech data Sin. In this embodiment this time The 甬 decoder 110 is a -bull / A-law decoder. The second operation 120 includes an echo canceller using affine projection (AP). This echo canceller 125 based on affine projection (Ap) Since this time, the linear sample is Sin removed-the echo estimation signal is generated to generate the linear data sample S0t. The output encoder 13G provides the pre-packet speech compression. In the embodiment, this output encoder 130 Is a use including international two, Union (ITU) -T international standard G.7xx series of any compression standard for low bit rate sound (LBRV) to compress the G.7xx encoder from the sound channel data of 120. This compressed voice data is transmitted through a network. It is sent to the far end. The receiving input decoder 14 decompresses the voice data received from this first far end on the network 145. This decompression technology is compatible with the compression technology used on the output output encoder. The echo channel 120 receives Rin from the receive input decoder 14 and sends out Rout linear data samples. The receive output encoder 150 encodes the linear data samples Rout to be sent to this first near end; z-law and A-law Encoded voice. -8- * ^ [^ Degrees in use § National Standard (CNS) A4 specification (210 X 297 mm) binding € 5. Description of the invention (6) The ability to transmit or packetize data in IM30 capacity is self-contained This send 1 and receive input decoder, and any network on the receive output decoder 195. This network 145 can be the Internet, an enterprise intranet, an external network, a local area network ( LAN), or a wide area network (WAN ). Send the input decoder ⑽Receive = From the encoding head of 罔 Road 145 and decode this coded speech into the linear language Jinbei Sm. In one embodiment, the input decoder ⑽ is a rule of law decoder The echo channel 17 includes an echo canceller 175 using an affine projection. This echo canceler 175 based on affine projection samples the linear data from this sample and removes the echo estimation signal to generate a linear data sample. The output output encoder 18 provides speech compression before packetization. 纟-In the embodiment, this output output encoder is just used for low-bits including the International Telecommunication Union (ITU) _T international standardization g series. Any compression standard of rate sound (LBRV) is used to compress the voice data Sout G.7xx encoder from the echo channel 170. The compressed speech data is sent to the receiving device at the remote end. The receiving input decoder 190 decodes the voice data received from this second remote end. This decompression technique is compatible with the compression technique used on the output encoder 180. The echo channel 170 receives the scaling from the receiving input decoder 19 and sends this
Rout線性資料取樣。接收輸出編碼器19〇將此線性資料取 樣Rout編碼成預備送出到網路145和此第二遠端的心法則 和A-法則編碼語音。在一實施例中,送出輸入解碼器 160,回晋通道〗70,送出輸出解碼器18〇,接收輸入解碼 奋190,和接收輸出編碼器195被整合進一數位信號處理器 -9 - 本纸張尺度適用中國國家標準(CNS) A4規格(21〇 X 297公董) 583851 A7 B7 五、發明説明(7 ) 165。 圖2是一圖示根據本發明的一實施例,在圖1中所示的 用於此基於仿射投影的回音消除器125的系統模型之圖 形。此系統模型200包含一系統210,一加法器220,一適 應性濾波器230,和一減法器240。 此系統模型200建立一回音消除處理的模型。此回音消 除處理可被塑造成一識別一未知的線性系統的系統識別問 題。此系統的輸入是一輸入序列u ( k )。系統2 1 0特性化此 系統的行為。系統2 10可被塑造成一具有權值向量w = [Wi,W2,...,wN]的有限脈衝響應(FIR)滤波器。此系統輸出 由公式所給出·· y(k) = WTu(k) ( 1 ) 其中是此權值向量W的轉置。此權值向量W是未知 的。 加法器2 2 0將一隨機雜訊序列v ( k )加到此系統輸出y ( k ) 上以產生想要的輸出d ( k ) ^此適應性濾波器230被塑造成 一具有權值向量w = [Wl,W2,...,WN]的有限脈衝響應濾波 器。減法器240將想要的輸出d ( k )自此適應性濾波器的輸 出減去以產生一誤差e ( k )。此誤差e ( k )被用以調整或更 新此權值向量W以便在某目標函數下(例如最小均方),誤 差e ( k)被最小化。權值向量说被更新以便其接近此權值向 量W。此權值向量w,因此代表此權值向量w的一估計。 圖3是一圖示根據本發明的一實施例,在圖1中所示的 一基於仿射投影的回音消除器125之圖形。回音消除器 -10- 本纸張尺度制+ g g家標半(CNS) A4規格(210X297公爱丁Rout linear data sampling. The receiving output encoder 19 encodes this linear data sample Rout to encode the heart and A-laws to be sent to the network 145 and the second far end. In one embodiment, the input decoder 160 is sent out, the return channel 70 is sent, the output decoder 18 is received, the input input decoder 190 is received, and the receive output encoder 195 is integrated into a digital signal processor-9.-This paper The standard is applicable to China National Standard (CNS) A4 specification (21 × X 297 public directors) 583851 A7 B7 V. Description of invention (7) 165. Fig. 2 is a diagram illustrating a system model for the affine projection-based echo canceller 125 shown in Fig. 1 according to an embodiment of the present invention. The system model 200 includes a system 210, an adder 220, an adaptive filter 230, and a subtractor 240. This system model 200 builds a model of the echo cancellation process. This echo cancellation process can be modeled as a system identification problem identifying an unknown linear system. The input to this system is an input sequence u (k). System 2 1 0 characterizes the behavior of this system. System 2 10 can be shaped as a finite impulse response (FIR) filter with a weight vector w = [Wi, W2, ..., wN]. This system output is given by the formula y (k) = WTu (k) (1) where is the transpose of this weight vector W. This weight vector W is unknown. The adder 2 2 0 adds a random noise sequence v (k) to the system output y (k) to produce the desired output d (k). The adaptive filter 230 is shaped into a weighted vector w = [Wl, W2, ..., WN] finite impulse response filters. The subtractor 240 subtracts the desired output d (k) from the output of the adaptive filter to produce an error e (k). This error e (k) is used to adjust or update this weight vector W so that the error e (k) is minimized under an objective function (such as the least mean square). The weight vector is updated so that it approaches this weight vector W. This weight vector w therefore represents an estimate of this weight vector w. Fig. 3 is a diagram illustrating an echo canceller 125 based on affine projection shown in Fig. 1 according to an embodiment of the present invention. Echo Canceller -10- Paper Size + g g House Standard Half (CNS) A4 Specification (210X297 Male Eding
裝 訂Binding
583851 A8 B8 C8 D8583851 A8 B8 C8 D8
六、申請專利範_ 125包含一適應性滤波器3 10和一延遲估計器32〇。 此適應性濾波器3 10估計一使用仿射投影(a ρ )更新的回 音通道120 (圖1)之通道權值向量W。如圖1所述,回音通 道120接收一送出輸入序列Sin和一接收輸入序列Rin。適 應性濾波器310被用以藉延遲估計器320以計算這些延 遲。通道權值向量W具有一第一長度mi。在一實施例 中,此第一長度Ml是1024。 延遲估計器3 2 0使用由適應性濾波器3 1 0所提供的估計 的通道權值向量W以決定在此回音通道12〇中的大部分延 遲。延遲估計器3 2 0提供這些估計的延遲給適應性濾波器 3 3 0。 適應性濾波器3 3 0使用此仿射投影更新和來自延遲估計 器3 2 0的估計延遲以估計多個短權值向量。這些短權值向 量對應到這些稀疏多路徑通道的脈衝響應。這些短權值向 量中的每個的長度典型地短於此第一長度Μ1。 適應性濾波器3 1 0和3 3 0使用一仿射投影更新規則以估 計通道權值向量。此仿射投影方法被用以加速特別用於彩 色輸入之正規化最小均方(NLMS )技術的收斂。此仿射投 影以多重過去輸入向量為基礎來更新這些權值,然而此正 規化最小均方以最近輸入向量為基礎來更新這些權值。仿 射投影更新的規則說明如下。 此輸入序列u(k)可被塑造成一 Ρ次的自動回歸處理,表 示為AR(P): ρ «(k)= Va; *u(k-i)^z(k) (2) -11 - 本紙張尺度適用中國國家標準(CNS) A4規格(210 x 297公釐) 583851 A7 B7 五、發明説明(9 ) 其中z ( k)是具有單位變異數的白序列。 假設P是事先已知,則u(k)的取樣可被寫為 量u ( k ),或: 一(Mx 1)行向 uT(k) = [u(k),u(k-l),...,u(k-M+l)] (3) 此AR(P)處理接著可被寫為: P u(k) = [a!· *u(k-i) + z(k) i=l =U(k)*a + z(k) 其中U(k)是過去向量的P個聚集: (4) U(k) =[u(k-l), u(k-2),.. ., u(k-P)] (5) 且z ( k )是一白隨機序列的取樣之(Mxl )行向量·· zT(k) = [z(k), z(k-l),. . ., z(k-M+l)] (6) a的參數之最小平方估計是由公式所給出: a(k) = [U丁(k^l^k)]·1 *uT(k)*u(k) ⑺ 其中UT(k)*U(k)被假定是P階且*表示相乘。 此對//= 1的仿射投影遞迴更新規則是由以下運算集合所 定義: φ(Ι〇 =u(k)-U(k)*a(k) ={I-U(k)3^ [UT(k)*U(k)]·1 *UT(k)}*u(k) (8) -12- 本紙張尺度適用中國國家標準(CNS) A4規格(210x 297公釐) 583851 A7 B76. The patent application Fan_125 includes an adaptive filter 310 and a delay estimator 320. This adaptive filter 3 10 estimates a channel weight vector W of the echo channel 120 (Fig. 1) updated using the affine projection (a ρ). As shown in FIG. 1, the echo channel 120 receives a sending input sequence Sin and a receiving input sequence Rin. The adaptive filter 310 is used to borrow the delay estimator 320 to calculate these delays. The channel weight vector W has a first length mi. In one embodiment, the first length M1 is 1024. The delay estimator 3 2 0 uses the estimated channel weight vector W provided by the adaptive filter 3 1 0 to determine most of the delays in this echo channel 120. The delay estimator 3 2 0 provides these estimated delays to the adaptive filter 3 3 0. The adaptive filter 3 3 0 uses this affine projection update and the estimated delay from the delay estimator 3 2 0 to estimate multiple short weight vectors. These short weight vectors correspond to the impulse responses of these sparse multipath channels. The length of each of these short weight vectors is typically shorter than this first length M1. The adaptive filters 3 1 0 and 3 3 0 use an affine projection update rule to estimate the channel weight vector. This affine projection method is used to accelerate the convergence of the normalized least-mean-square (NLMS) technique especially for color input. This affine projection updates these weights based on multiple past input vectors, whereas this normalized least mean square updates these weights based on the most recent input vector. The rules for affine projection update are explained below. This input sequence u (k) can be shaped as a P-time automatic regression process, expressed as AR (P): ρ «(k) = Va; * u (ki) ^ z (k) (2) -11-this Paper size applies Chinese National Standard (CNS) A4 specification (210 x 297 mm) 583851 A7 B7 V. Description of invention (9) where z (k) is a white sequence with unit variation. Assuming that P is known in advance, the sampling of u (k) can be written as the quantity u (k), or: One (Mx 1) line direction uT (k) = [u (k), u (kl) ,. .., u (k-M + l)] (3) This AR (P) process can then be written as: P u (k) = [a! · * U (ki) + z (k) i = l = U (k) * a + z (k) where U (k) is the P aggregation of past vectors: (4) U (k) = [u (kl), u (k-2), ... ,, u (kP)] (5) and z (k) is a sampled (Mxl) row vector of a white random sequence. zT (k) = [z (k), z (kl),..., z ( k-M + l)] (6) The least square estimate of the parameter of a is given by the formula: a (k) = [U 丁 (k ^ l ^ k)] · 1 * uT (k) * u ( k) ⑺ where UT (k) * U (k) is assumed to be of order P and * indicates multiplication. The affine projection recursive update rule for // = 1 is defined by the following set of operations: φ (Ι〇 = u (k) -U (k) * a (k) = {IU (k) 3 ^ [ UT (k) * U (k)] · 1 * UT (k)} * u (k) (8) -12- This paper size applies to China National Standard (CNS) A4 (210x 297 mm) 583851 A7 B7
五、發明説明(1〇 ) e(k) =d(k)~uT(k)* W(k) (9) *(k十 1) = w(k) + [φ(1ς)/ (φτ(ΐζ)* (j)(k))]*e(k) (10) 其中你(K)是由適應性濾波器3 1 〇所估計的通道權值向量 或由適應性濾波器3 3 〇所估計的各別短權值向量。 已證明如果u (k )是一 ρ次的自動回歸處理,則yK)是一 其自動回知係數的最小平方估計且φ (k)三z(k)。換句話說, φ ( k)是一其元素為一白隨機序列的估計之向量。 圖4 A是一圖示根據本發明的一實施例,在圖3中所示的 一用於基於仿射投影的回音消除器之適應性濾波器3 1 〇的 圖形·。此基於仿射投影的適應性濾波器3 1 0包含一自動回 歸(A R)係數估計器4 1 〇,一隨機估計器4 2 〇,一誤差估 計器4 j 0 ’和一權值更新器4 4 0。 此自動回歸係數估計器4 1 〇估計在使用此過去接收輸入 序列和現在接收序列的第一更新速率上的此自動回歸係數 向量备(k )。此自動回歸係數估計器4 1 0產生此使用方程式 (7 )的自動回歸係數向量。 隨機估計器4 2 0估計在使用此估計的自動回歸係數向量 的第二更新速率上的隨機序列φ (k)。隨機估計器4 2 0使用 方程式(8 )以決定此隨機序列φ (k)。 誤差估計器4 3 0估計在使用此第二序列,此接收序列, 和此估計的通道權值向量的第二更新速率上的誤差。此誤 差估計器4 3 0使用方程式(9 )以計算此誤差e ( k )。 權值更新器4 4 0更新在使用此估計的誤差,和此估計的 -13- 本紙張尺度適用中國國家標準(CNS) A4規格(210X297公釐) A7 A7V. Description of the invention (1〇) e (k) = d (k) ~ uT (k) * W (k) (9) * (k ten 1) = w (k) + [φ (1ς) / (φτ (ΐζ) * (j) (k))] * e (k) (10) where you (K) is the channel weight vector estimated by the adaptive filter 3 1 〇 or by the adaptive filter 3 3 〇 The estimated individual short weight vectors. It has been proved that if u (k) is a ρ-time automatic regression process, then yK) is a least square estimate of its auto-learning coefficient and φ (k) is three z (k). In other words, φ (k) is a vector of estimates whose elements are a white random sequence. Fig. 4A is a diagram illustrating an adaptive filter 3 1 0 for an echo canceller based on affine projection shown in Fig. 3 according to an embodiment of the present invention. This affine projection-based adaptive filter 3 1 0 includes an automatic regression (AR) coefficient estimator 4 1 0, a random estimator 4 2 0, an error estimator 4 j 0 ', and a weight updater 4 4 0. The automatic regression coefficient estimator 4 10 estimates the automatic regression coefficient vector (k) at the first update rate using the past received input sequence and the current received sequence. This automatic regression coefficient estimator 4 1 0 generates this automatic regression coefficient vector using equation (7). The random estimator 4 2 0 estimates a random sequence φ (k) at a second update rate using the estimated automatic regression coefficient vector. The random estimator 4 2 0 uses equation (8) to determine this random sequence φ (k). The error estimator 430 estimates the error at the second update rate using the second sequence, the received sequence, and the estimated channel weight vector. This error estimator 4 3 0 uses equation (9) to calculate this error e (k). The weight updater 4 4 0 updates the error in using this estimate, and the estimated -13- This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) A7 A7
k機序列的第二更新速率上的通道權值向量你。此權值更 新器.4 4 0使用方程式(1 〇)以更新此通道權值。 此第一和第二更新速率可以相同或不同。在一實施例 中,此第一更新速率是比第二更新速率慢的。此第二更新 逮率是更新迥圈中的每個重複的速率。此第一更新速率是 更新迥圈中的每κ個重複的速率,其中κ是一正整數。在 —貫施例中,κ等於1 0 〇。換句話說,此自動回歸係數估 计器4 1 0在每κ個重複上產生一新的結果而隨機估計器 4 2 0,誤差估計器4 3 〇,和權值更新器4 4 〇在每個重複上 產生新的結果。 圖.4Β是一圖示此根據本發明的一實施例,在圖3中所示 的一用於基於仿射投影的回音消除器之適應性濾波器3別 的圖形。此適應性濾波器33〇包含一輸入分離器45〇,°§個 部分自動回歸係數估計器460!到460s,S個部分隨機估計 器470#] 470S,一誤差估計器48〇,和一權值更新器49q/ 輸入分離器450將接收輸入序列u(k)分成s個部分輸入 序列。這些部分輸入序列的每個被一來自由延遲估計器 320 (圖3 )所提供延遲的對應延遲所延遲且由如下之一部 分隨機序列和一由一部分自動回歸係數向量所加權的過^ 部分輸入序列的和來代表:The channel weight vector on the second update rate of the k-machine sequence. This weight updater. 4 4 0 uses equation (1 0) to update this channel weight. The first and second update rates may be the same or different. In one embodiment, the first update rate is slower than the second update rate. This second update rate is the rate at which each iteration in the update cycle is repeated. This first update rate is the rate per k repeats in the update cycle, where k is a positive integer. In one embodiment, κ is equal to 100. In other words, the automatic regression coefficient estimator 4 1 0 produces a new result on every k repeats while the random estimator 4 2 0, the error estimator 4 3 0, and the weight updater 4 4 0 Repeatedly produce new results. Fig. 4B is a diagram illustrating an adaptive filter 3 for an echo canceller based on affine projection shown in Fig. 3 according to an embodiment of the present invention. The adaptive filter 33 includes an input separator 45, a partial automatic regression coefficient estimator 460! To 460s, S partial random estimators 470 #] 470S, an error estimator 48, and a weight The value updater 49q / input separator 450 divides the received input sequence u (k) into s partial input sequences. Each of these partial input sequences is delayed by a corresponding delay from the delay provided by the delay estimator 320 (FIG. 3) and is partially partially randomized by one of the following and an overlying partial input sequence weighted by a partial automatic regression coefficient vector And to represent:
Ui(k) = Ui(k)*ai + z, (k), i = 1. . ., S (11) 此s個部分自動回歸係數估計器46〇i到46〇s被耦合到輪 入分離器45 0以接收此s個部分輸入序列u丨㈨,其中丄二 -14- 583851 A7 _____ B7 五、發明説明(12 1 ~" : 1··. ’ S。這些部分自動回歸係數估計器46〇1到46〇s的每個 估計在使用此過去部分輸入序列和此部分輸入序列的第一 更新速率上的此部分自動回歸係數向量: 祕)=[Ui'k)*!^)]·1 *U,T(k)*u,(k),i = 1,…S (12) 此S個部分隨機估計器47(^到470s分別被耦合到這些部 分自動回歸係數估計器46(^到460s。這些部分隨機估計器 47(^到470s的每個估計在使用此估計的部分自動回歸係數 向量的第二更新速率上的此部分隨機序列: φ/k) —叫!〇*雖),卜1,···』 (13) 誤差估計'器480估計在使用此送出輸入序列sin或d(k), 這些部分輸入序列,和這些估計的短權值向量的第二更新 速率上的誤差: e(k) = d(k)- Σ UiWiT,i =1,...,5 (14) 權值更新器4 9 0更新在使用此估計的誤差和此估計的部 分隨機序列的第二更新速率上的短權值向量Wi(k):Ui (k) = Ui (k) * ai + z, (k), i = 1..., S (11) The s partial automatic regression coefficient estimators 46〇i to 46〇s are coupled to the rotation The separator 45 0 receives this s part of the input sequence u 丨 ㈨, among which 丄 -14- 583851 A7 _____ B7 V. Description of the invention (12 1 ~ ": 1 ··. 'S. These parts are automatically regression coefficient estimated Each of the estimates of the generators 46〇1 to 46〇s automatically uses this part of the regression coefficient vector on this first part of the input sequence and the first update rate of this part of the input sequence:)) = (Ui'k) *! ^) ] · 1 * U, T (k) * u, (k), i = 1, ... S (12) The S partial random estimators 47 (^ to 470s are respectively coupled to these partial automatic regression coefficient estimators 46 (^ To 460s. These partial random estimators 47 (Each estimate of ^ to 470s is this partial random sequence at the second update rate of the partial automatic regression coefficient vector using this estimation: φ / k) —called! 〇 * Although), Bu 1, ... "(13) The error estimator 480 estimates the input sequence sin or d (k), these partial input sequences, and the second update rate of these estimated short weight vectors. Error: e ( k) = d (k)-Σ UiWiT, i = 1, ..., 5 (14) Weight updater 4 9 0 updates on the second update rate using the error of this estimate and the partial random sequence of this estimate Short weight vector Wi (k):
Wi(k+D= w《k) + [Wk^'k)* 她川〜⑻,I = 1,· · ·, S (15) 此第一和第二更新速率可以相同或不同。在一實施例 中,此第一更新速率是比第二更新速率慢的。此第二更#斤 速率是更新迥圈中的每個重複的速率。此第一更新速率4 更新迥圈中的每K個重複的速率,其中K是一正整數。& -15- 五、發明説明(13 ) 一實施例中,K等於100。換句話說,此S個部分自動回 歸係數估計器460】到460s在每κ個重複上產生一新的結果 而此S個部分隨機估計器46〇#j46〇s,誤差估計器,和 推值更新器4 9 0在每個重複上產生新的結果。 圖5疋一圖示此根據本發明的一實施例,在圖2中所示 的一用於基於仿射投影的回音消除器之延遲估計器3 2 〇的 圖形。延遲估計器3 2 0包含一峰值定位器51〇和一辛值消 除器5 2 0。 延遲估計器3 2 0藕由估計的通道權值向量w ( k )以估計 在回音通道120(圖1)中的大部分延遲。延遲估計器32〇 提供此估計的延遲給適應性濾波器3 3〇(圖3)使用於適應 上。延遲估計器320基本上定位許多在脈衝響應上的許多 峰值,正如此估計的權值向量w(k)所提供的元件。 睾值足位器510決定這些峰值為在一搜索區域内的權值 之最大值。典型地定位L個峰值,其中L是一從丨到5的正 整數。在一實施例中,L等於5。這些峰值是位於與其它 峰值離開一預定的距離之内。峰值定位器5丨〇包含一平方 大小計算機5丨5以計算決定這些峰值的值之估計的通道權 值向量的元素的平方大小。首先,此最高的峰值被決定為 在通道權值向量W(k)的權值中之最高值。然後,第二最 高t峰值是位於涵蓋此最高峰值的區域外。此區域包含在 此最高峰值的任一邊的L i個取樣。在一實施例中,乙i -25。接著,此第三最高的峰值是位於涵蓋此第二最高的 峰值的區域外。此區域包含在此第二最高峰值的任一邊的 -16- 本紙張尺度適财國國家標準(CNS) A4規格(210X 297公爱y 583851Wi (k + D = w 《k) + [Wk ^ 'k) * She Chuan ~ ⑻, I = 1, · ·, S (15) The first and second update rates may be the same or different. In one embodiment, the first update rate is slower than the second update rate. This second rate is the rate of each repetition in the update cycle. This first update rate 4 updates the rate of every K repetitions in the loop, where K is a positive integer. & -15- V. Description of the Invention (13) In one embodiment, K is equal to 100. In other words, the S partial automatic regression coefficient estimators 460] to 460s produce a new result on every k repeats and the S partial random estimators 46 ° # j46 ° s, the error estimator, and the push value The updater 490 produces new results on each iteration. Fig. 5 illustrates a graph of a delay estimator 3 2 0 for an echo canceller based on affine projection shown in Fig. 2 according to an embodiment of the present invention. The delay estimator 3 2 0 includes a peak locator 510 and a sinusoidal canceller 5 2 0. The delay estimator 3 2 0 藕 estimates the majority of the delay in the echo channel 120 (Figure 1) from the estimated channel weight vector w (k). The delay estimator 32 provides this estimated delay to the adaptive filter 3 3 0 (Fig. 3) for adaptation. The delay estimator 320 basically locates many peaks in the impulse response, and the components provided by the weight vector w (k) are thus estimated. The testicular foot positioner 510 determines that these peaks are the maximum value of the weights in a search area. L peaks are typically located, where L is a positive integer from 5 to 5. In one embodiment, L is equal to five. These peaks are located within a predetermined distance from other peaks. The peak locator 5 includes a square size computer 5 to calculate the square size of the elements of the estimated channel weight vector that determine the values of these peaks. First, this highest peak is determined as the highest value among the weights of the channel weight vector W (k). Then, the second highest t-peak is outside the area covering this highest peak. This area contains L i samples on either side of this highest peak. In one embodiment, B i -25. Then, the third highest peak is outside the area covering the second highest peak. This area contains -16 on either side of this second highest peak. This paper is sized for the National Standard (CNS) A4 size (210X 297 Public Love 583851)
L2個取樣。在一實施例中,L2 = 25。此處理繼續直到l 個辛值已被定位。 峰值消除器5 2 0消除由峰值定位器5 ][ 〇所定位的這些l 個峰值中的一錯誤峰值。當其值小於一臨界值時此錯誤^峰 值被識別出。在一實施例中,此臨界值等於点*最高峰 值,其中冷是一在0.4和0.8間的數目。在一實施例中, /5 =0.6。在所有錯誤峰值都被消除後,這些剩下的峰值提 供延遲,或這些峰值的位置。 圖6疋一圖示一根據本發明的一實施例,用於回音消除 之處理6 0 0的流程圖。 一開始’處理6 0 0起始化此迥圈重複指標k = 1,濾波器 長度M = M1,重複的數目Q = Q1,通道權值向量w(k), 自動回歸係數向量a,隨機序列φ ( k ),誤差e ( k ),和過去 接收輸入序列U(k)(方塊6 10)。在一實施例中,Ml=256, 5 12,或1 〇 2 4。接著,處理ό 0 0使用此仿射投影更新來執 行適應性遽波以估計此通道權值向量W(k)(方塊620)。然 後,處理6 0 0決定此重複指標是否等於q丨(方塊6 2 5 )。如 果不是,處理6 0 0增加此重複指標k (方塊6 2 7 )且回到方 塊6 2 0。否則,處理6 〇 〇使用最終估計的通道權值向量 W(k) = W(Ql + l)(方塊6 3 0)以估計這些延遲。 接著,處理6 0 0起始化此重複指標k = Q 1,濾波器長度 M = M2,重複的數目 Q = Q2,參數 W(k),a(k),φ (k),e(k), U(k) ’和部分輸入序列R丨n以用於每個部分適應性濾波器 (方塊6 4 0 )。Μ 2可以與Μ 1相同或小於Μ 1。在一實施例 -17- 本纸張尺度適用中國國家標準(CNS) Α4規格(210 X 297公釐)L2 samples. In one embodiment, L2 = 25. This process continues until l symplectic values have been located. The peak canceller 5 2 0 eliminates one of the l peaks located by the peak locator 5] [〇. This error is detected when its value is less than a critical value. In one embodiment, this critical value is equal to the point * highest peak value, where cold is a number between 0.4 and 0.8. In one embodiment, /5=0.6. After all erroneous peaks have been eliminated, these remaining peaks provide a delay, or the location of these peaks. Fig. 6 illustrates a flowchart of a processing for echo cancellation 600 according to an embodiment of the present invention. At the beginning, process 6 0 0 to initialize this loop repeat index k = 1, filter length M = M1, number of repeats Q = Q1, channel weight vector w (k), automatic regression coefficient vector a, random sequence φ (k), error e (k), and past received input sequence U (k) (block 6 10). In one embodiment, M1 = 256, 512, or 104. Next, the process uses this affine projection update to perform an adaptive chirp to estimate the channel weight vector W (k) (block 620). Then, processing 6 0 0 determines whether this repeated index is equal to q 丨 (block 6 2 5). If not, the process 6 0 increases this repetition index k (block 6 2 7) and returns to block 6 2 0. Otherwise, process 600 uses the final estimated channel weight vector W (k) = W (Ql + l) (block 6 3 0) to estimate these delays. Next, process 6 0 0 to initialize this repetition index k = Q 1, filter length M = M2, number of repetitions Q = Q2, parameters W (k), a (k), φ (k), e (k ), U (k) 'and the partial input sequence Rn for each partial adaptive filter (block 640). M 2 may be the same as or smaller than M 1. In an embodiment -17- this paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm)
裝 雙 583851 A7 __________ Β7 五、發明説明(π ) 中M1 1024 ’ Μ 2 = 6 0到1 〇 〇。然後,處理6 〇 〇使用此仿 射/又,〜更新來執行適應性濾波以估計短權值向量Wi(k) (、鬼5〇)在方塊650中的計算和更新基本上是與方塊 6 2:中的计算和更新相同。以這種方式,.相同的濾波器具 月注κ現可用於此兩級上。或者,具體實現兩不同的適應性 濾波器。 然後處理6 0 〇決定此重複指標是否等於Q 2 (方塊6 5 5 )。 如果不是,處理6 0 0增加此重複指標k (方塊6 5 7 )且回到 方塊6 5 0。否則,終止處理6 〇 〇。 圖7是一圖示一根據本發明的一實施例,用於在圖6中 所不使用仿射投影更新的適應性濾波之處理6 2 〇的流程 圖。 一開始,處理6 2 0計算此短期平均功率,stavp,和長期 平均功率,Rinphat(方塊71〇)。然後,處理62〇決定stavp 是否小於Rinphat(方塊710)超過一預定的數目(方塊 715)。在一實施例中,此數目是2〇分貝。如果是這樣, 處理6 2 0凍結此估計的通道權值向量(方塊7 2 〇 )且如方程 式(9 )所示估計誤差e ( k )(方塊7 2 5 ),然後終止。否則, 處理6 2 0儲存此估計的自動回歸係數向量a(n)(方塊 7 3 0 ) 〇 然後,處理6 2 0決定是否是該更新此自動回歸係數向量 a的時候(方塊7 3 5 )。在一實施例中,此第一更新速率對 應到每R次重複,其中R = 1 0 0。如果此時不是更新的時 候,此估計的自動回歸係數向量被保持與在方塊7 3 0中所 -18- ^紙張尺度適用中國國家標準(CNS) A4規格(210 X 297公釐)~" " 'Equipment double 583851 A7 __________ B7 5. In the description of the invention (π), M1 1024 ′ Μ 2 = 60 to 100. Then, process 600 uses this affine / renewal to perform adaptive filtering to estimate the short weight vector Wi (k) (, ghost 50). The calculation and update in block 650 is basically the same as block 6 The calculations and updates in 2: are the same. In this way, the same filter with monthly note κ is now available on both stages. Alternatively, implement two different adaptive filters. It then processes 6 0 0 to determine whether this repeat indicator is equal to Q 2 (block 6 5 5). If not, process 6 0 increases this repeating index k (block 6 5 7) and returns to block 6 5 0. Otherwise, the processing is terminated 600. FIG. 7 is a flowchart illustrating a process 6 2 0 for adaptive filtering not using affine projection update in FIG. 6 according to an embodiment of the present invention. Initially, process 6 2 0 calculates this short-term average power, stavp, and long-term average power, Rinphat (block 71). Then, the process 62 determines whether stavp is less than Rinphat (block 710) by more than a predetermined number (block 715). In one embodiment, this number is 20 decibels. If so, the process 6 2 0 freezes this estimated channel weight vector (block 7 2 0) and estimates the error e (k) as shown in equation (9) (block 7 2 5), and then terminates. Otherwise, processing 6 2 0 stores the estimated automatic regression coefficient vector a (n) (block 7 3 0). Then processing 6 2 0 determines whether it is time to update the automatic regression coefficient vector a (block 7 3 5). . In one embodiment, this first update rate corresponds to every R repetitions, where R = 1 0 0. If it is not the time to update at this time, the estimated automatic regression coefficient vector is maintained as described in box 7-30. ^ The paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) ~ " " '
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583851 A7 B7 五、發明説明( 存的先前值相同(方塊7 4 5 )。否則,根據方程式(7 )以更 新此自動回歸係數向量έ (方塊7 4 0 )。接著,處理6 2 0使 用方程式(8 )以估計此隨機序列φ (k)(方塊7 5 0 )。然後,處 理6 2 0使用方程式(9 )以估計此誤差e(k)(方塊7 5 5 )。接 著,處理620使用方程式(10)以更新此通道權值向量W(k) (方塊7 6 0)且接著終止。 圖8是一圖示一根據本發明的一實施例,用於在圖6中 所示之延遲估計之處理6 3 0的流程圖。 一開始,處理6 3 0起始化此峰值指標i = i且定決此最高 峰值,peak(k) = max{W(k)},其中W(k)是由此適應性濾波 器所提供的通道權值向量(方塊8 1 0 )。使用估計的通道權 值向量的大小平方以決定此最高峰值。接著,處理6 3 0決 足位於圍繞peak(k)的視窗外的下個峰值,next peak = max{W(k)-R},其中R是圍繞peak(i)的區域,此最近定位 的峰值(方塊8 2 0 )。在一實施例中,r涵蓋在總共5 i個取 樣的peak(i)的任一邊之25個取樣。然後,處理63〇決定 next—peak是否大於石*最高學值(方塊830)。在一實施例 中,冷=0.6。如果next一peak並不大於0 *最高峰值,則 next一peak被假設為一錯誤的峰值且被消除(方塊8 4 〇 )。否 則’處理6 3 0決定此peak(i)是next—peak (方塊8 5 0 )。然後, 處理630決定到目前為止所定位的辛值數目是否等於$, 其中s是預足被定位的峰值總數目(方塊86〇)。在一實施 例中,S等於3到5。如果不是,處理6 3 〇增加此峰值指標 id+l (方塊8 7 0 ),且然後回到方塊820。否則,處理63〇 -19- 本紙張尺度適用中國國家標準(CNS) A4規格(210X297公爱·)583851 A7 B7 V. Description of the invention (the previous values stored are the same (block 7 4 5). Otherwise, according to equation (7) to update this automatic regression coefficient vector (block 7 4 0). Then, process 6 2 0 using the equation (8) to estimate this random sequence φ (k) (block 7 5 0). Then, process 6 2 0 uses equation (9) to estimate this error e (k) (block 7 5 5). Then, process 620 uses Equation (10) updates this channel weight vector W (k) (block 7 6 0) and then terminates. Figure 8 is a diagram illustrating an embodiment according to the present invention for the delay shown in Figure 6. Estimated flowchart of processing 6 3 0. Initially, processing 6 3 0 initializes the peak index i = i and determines the highest peak, peak (k) = max {W (k)}, where W (k ) Is the channel weight vector provided by this adaptive filter (block 8 1 0). The size of the estimated channel weight vector is used to determine this highest peak. Then, the processing 6 3 0 is determined to be located around the peak ( k) the next peak outside the window, next peak = max {W (k) -R}, where R is the area around peak (i), this most recently located peak (block 8 2 0 In one embodiment, r covers 25 samples on either side of a total of 5 i samples of peak (i). Then, process 63 determines whether next-peak is greater than the highest value of stone * (block 830). In one embodiment, cold = 0.6. If next-peak is not greater than 0 * highest peak, then next-peak is assumed to be a false peak and eliminated (block 8 4 0). Otherwise 'Process 6 3 0 decision This peak (i) is next_peak (block 850). Then, the process 630 decides whether the number of pinpoints that have been located so far is equal to $, where s is the total number of peaks that have been pre-positioned (block 86). In one embodiment, S is equal to 3 to 5. If not, process 6 3 0 increases the peak index id + 1 (block 8 7 0), and then returns to block 820. Otherwise, process 63 0-19-this Paper size applies Chinese National Standard (CNS) A4 specification (210X297 public love ·)
裝 •線 583851Mounting line 583851
決足對應到這些peak(i),其中丨=丨,,s,的位置之延遲 (方塊8 8 0 )。接著終止處理6 3 〇。 圖9疋一圖示根據本發明的一實施例,用於使用仿射投 影更新的部分適應性濾波之處理6 5 〇的流程圖。 一開始,處理6 5 0將此接收輸入序列分成多個部分輸入 序列(方塊9 0 2 )。這些部分輸入序列的每個被一由此延遲 估計器所提供的延遲中之一所延遲。每個部分輸入序列是 由一部分隨機序列和一由一部分自動回歸係數向量所加權 的過去部分輸入序列之和所代表。接著,處理65〇起始化 用於S個部分適應性濾波器元件之迥圈的濾波器指標(方 塊9 0 5 )。應注意雖然此流程圖顯示此部分適應性濾波器 的一順序操作,但這些操作可以順序或平行的方式來執 行。 然後,處理65 0計算與此部分輸入序列有關聯的短期平 均功率,StaVPi,和長期平均功率,Rinphati (方塊9ι〇)。 然後.,處理6 5 0決定stavp是否小於Rinphat超過一預定的數 目(方塊9 1 5 )。在-實施例中,此數目是2 〇分貝。如果是 這樣,處理65 0凍結此估計的通道權值向量(方塊92〇)且 如方程式(14)所示估計誤差e(k)(方塊92 5 )且然後終止。 否則,處理6 5 0儲存此估計的自動回歸係數向量 (方塊93 0” 然後處理6 5 〇決足疋否是該更新此部分自動回歸係數 向量a的時候(方塊9 3 5 )。在一實施例中,此第一更新速 率對應到每R次重複,其中⑽。如果此時不是更新的 -20- 本紙張尺度適用中國國家標準(CNS) A4規格(210 X 297公袭^ -----------The delay corresponds to the position of these peak (i), where 丨 = 丨, s, (block 8 8 0). The processing is then terminated 6 3 0. Fig. 9 illustrates a flowchart of a process 650 for partially adaptive filtering updated using affine projection according to an embodiment of the present invention. Initially, process 6 50 divides this received input sequence into multiple partial input sequences (box 9 0 2). Each of these partial input sequences is delayed by one of the delays provided by this delay estimator. Each partial input sequence is represented by the sum of a partial random sequence and a past partial input sequence weighted by a portion of the automatic regression coefficient vector. Next, the process 65 starts the filter index for the loops of the S partially adaptive filter elements (block 905). It should be noted that although this flowchart shows a sequential operation of this part of the adaptive filter, these operations can be performed sequentially or in parallel. Then, process 65 0 calculates the short-term average power, StaVPi, and long-term average power, Rinphati (block 9), which are associated with this part of the input sequence. Then, processing 6 50 determines whether stavp is less than Rinnap by more than a predetermined number (block 9 1 5). In the example, this number is 20 decibels. If so, the process 65 0 freezes this estimated channel weight vector (block 920) and estimates the error e (k) as shown in equation (14) (block 92 5) and then terminates. Otherwise, process 6 50 stores this estimated auto-regression coefficient vector (box 93 0) and then process 6 50 to determine whether it is time to update this part of the auto-regression coefficient vector a (box 9 35). In one implementation In the example, this first update rate corresponds to every R repetitions, where ⑽. If it is not updated at this time -20- This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 public attack ^ ---- -------
裝 訂 € 583851 五、發明説明(18 時候,此估計的部分自動回歸係、數向量被保持盘在方塊 ::〇中所存的先前值相同(方塊945 )。否則,根據方程式 (1-)以更新此部分自動回歸係數向量§(方塊94〇)。接 者,處理650使用方程式(13)以估計此隨機序列φ(10(方 塊9〕〇)。然後,處理65 0決定此濾波器指標〖是否等於5 (万塊95 2 )。如果不是,處理65〇增加濾波器指標以到達 下個部分濾波(方塊9 5 3 )且回到方塊9丨〇。否則,處理 6 5 0使用方私式(9 )以估計此誤差e(k)(方塊9 5 5 )。接著, 處理6 5 0使用方程式(10)以更新此通道權值向量方 塊9 6 0)且接著終止。 使用具有部分適應性濾波器的仿射投影更新之此回音消 除收敛快於用於稀疏多路徑通道的正規化最小均方技術。 此基於仿射投影的回音消除可以銃同的方式來具體實現。 在一實施例中,此適應性濾波器3 1 〇的長度Μ 1 (也就是 說,此通道權值向量的大小)是1 〇 2 4且此適應性濾波器 3 3 0之元件的長度Μ 2的範圍從6 0到1 〇 〇,視此多路徑的 特性而定。應注意此適應性濾波器3 3 0的每個次-濾波器 可以有相同或不同的長度。回音消除器1 2 5可以用硬體或 軟體或此兩者的組合來具體實現。此外,此適應性濾波器 3 1 0和3 3 0可以一單一的適應性濾波器或分開的濾波器來 具體實現。 用於回音消除的A Ρ (2 )技術的這些結果顯示於圖10Α, 10B,10C,11A,11B,和11C中。此標準的AP(2)方法以 使用在G. 168測試2b ( Rin和Sin)上的資料檔案來測試。 -21 - 本紙張尺度適用中國國家標準(CNS) A4規格(210X297公爱) 裝 訂Binding € 583851 V. Description of the invention (At 18, the estimated partial automatic regression system, the number vector is kept in the previous value stored in the block :: 0 (block 945). Otherwise, update according to equation (1-) This part of the automatic regression coefficient vector § (block 94). Then, the process 650 uses equation (13) to estimate the random sequence φ (10 (box 9)). Then, the process 65 0 determines whether the filter index is Equal to 5 (10,000 blocks 95 2). If not, process 65 to increase the filter index to reach the next partial filter (block 9 5 3) and return to block 9 丨 〇. Otherwise, process 6 50 0 user-side private ( 9) to estimate this error e (k) (block 9 5 5). Then, process 6 5 0 uses equation (10) to update this channel weight vector (block 9 6 0) and then terminate. Use a partially adaptive filter The echo cancellation of the affine projection update of the router converges faster than the normalized minimum mean square technique used for sparse multipath channels. This echo cancellation based on affine projection can be specifically implemented in different ways. In one embodiment, The length of this adaptive filter 3 1 〇 The degree M 1 (that is, the size of the channel weight vector) is 10 2 4 and the length M 2 of the element of the adaptive filter 3 3 0 ranges from 60 to 100, depending on the multipath. It depends on the characteristics. It should be noted that each sub-filter of this adaptive filter 3 3 0 can have the same or different length. The echo canceller 1 2 5 can be specified by hardware or software or a combination of both. In addition, the adaptive filters 3 1 0 and 3 3 0 can be implemented as a single adaptive filter or separate filters. These results of the AP (2) technique for echo cancellation are shown in the figure 10A, 10B, 10C, 11A, 11B, and 11C. The standard AP (2) method is tested using the data file on G. 168 test 2b (Rin and Sin). -21-This paper standard applies to China National Standard (CNS) A4 Specification (210X297 Public Love) Binding
583851 A7 _________ B7 ___ 五、發明説明(19 ) 圖10 A是一圖示根據本發明的一實施例,在此第一適應 性階段之後用於非-稀疏通道的權值之圖形。 圖10B是一圖示根據本發明的一實施例,用於此非-稀疏 通道之前一萬個學習取樣的均方誤差(MSE)之圖形。 圖10C是一圖示根據本發明的一實施例,用於此非-稀疏 通道之一萬個取樣之後的此通道脈衝響應之估計的圖形。 圖11A是一圖示根據本發明的一實施例,在此第一適應 性階段之後用於稀疏通道的權值之圖形。 圖11B是一圖示根據本發明的一實施例,用於此稀疏通 道的前一萬個學習取樣均方誤差(MSE)之圖形。 圖Π C是一圖示根據本發明的一實施例,用於非-稀疏通 道之一萬個取樣之後的此通道脈衝響應之估計的圖形。 雖然本發明已參考到圖示的實施例來說明,此說明並不 欲以一限制的意味來解釋。這些圖示的實施例之不同的修 改,和本發明的其它實施例,可被視為在本發明的精神和 範圍内。 -22- 本紙張尺度適用中國國家標準(CNS) A4規格(210 X 297公釐)583851 A7 _________ B7 ___ V. Description of the invention (19) FIG. 10A is a graph illustrating the weights for non-sparse channels after this first adaptation phase according to an embodiment of the present invention. FIG. 10B is a graph illustrating the mean square error (MSE) of 10,000 learning samples before this non-sparse channel according to an embodiment of the present invention. FIG. 10C is a graph illustrating an estimate of the impulse response of the non-sparse channel for this channel after 10,000 samples according to an embodiment of the present invention. Fig. 11A is a graph illustrating weights for sparse channels after this first adaptive phase according to an embodiment of the present invention. Fig. 11B is a graph illustrating the mean square error (MSE) of the first 10,000 learning samples for this sparse channel according to an embodiment of the present invention. Figure ΠC is a graph illustrating an impulse response estimate for a non-sparse channel for this channel after 10,000 samples according to an embodiment of the present invention. Although the invention has been described with reference to the illustrated embodiments, this description is not intended to be construed in a limiting sense. Different modifications of these illustrated embodiments, and other embodiments of the invention, can be considered within the spirit and scope of the invention. -22- This paper size applies to China National Standard (CNS) A4 (210 X 297 mm)
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