JP2006033789A - Method, device, and program for estimating amount of echo path coupling; method, device, and program for controlling echoes; method for suppressing echoes; echo suppressor; echo suppressor program; method and device for controlling amount of losses on transmission lines; program for controlling losses on transmission lines; method, device, and program for suppressing multichannel echoes; and recording medium - Google Patents

Method, device, and program for estimating amount of echo path coupling; method, device, and program for controlling echoes; method for suppressing echoes; echo suppressor; echo suppressor program; method and device for controlling amount of losses on transmission lines; program for controlling losses on transmission lines; method, device, and program for suppressing multichannel echoes; and recording medium Download PDF

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JP2006033789A
JP2006033789A JP2004361521A JP2004361521A JP2006033789A JP 2006033789 A JP2006033789 A JP 2006033789A JP 2004361521 A JP2004361521 A JP 2004361521A JP 2004361521 A JP2004361521 A JP 2004361521A JP 2006033789 A JP2006033789 A JP 2006033789A
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Yoichi Haneda
Akitoshi Kataoka
Kiyotaka Sakauchi
章俊 片岡
陽一 羽田
澄宇 阪内
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Nippon Telegr & Teleph Corp <Ntt>
日本電信電話株式会社
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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    • Y02D70/00Techniques for reducing energy consumption in wireless communication networks
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    • Y02D70/12Techniques for reducing energy consumption in wireless communication networks according to the Radio Access Technology [RAT] in 3rd Generation Partnership Project [3GPP] networks
    • Y02D70/122Techniques for reducing energy consumption in wireless communication networks according to the Radio Access Technology [RAT] in 3rd Generation Partnership Project [3GPP] networks in 2nd generation [2G] networks

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for estimating the amount of echo path coupling which does not require determination of the double talking state and can estimate the amount of echo path coupling even under the double talking state, and to provide various devices that use the estimating method. <P>SOLUTION: The frequency for each input signal, to which a receiving signal and an echo signal are added, is analyzed, and receiving signal power and input signal power for each frequency band are computed from the frequency coefficient. The power ratio of the input signal power to the receiving signal power is computed for each frequency band; and the minimum value of the power ratio computed for each frequency band is updated, the updated minimum value of the power ratio is retained, and the minimum power ratio retained for each frequency band is output as the amount of echo path coupling for each frequency band. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

この発明は反響路結合量推定方法及びこの反響路結合量推定方法を用いたエコー抑圧方法、エコーサプレス方法、通話路上の損失量制御方法、多チャネルエコー抑圧方法これらの装置と、プログラムに関し、例えばマイクロホンとスピーカを用いたハンズフリー拡声通話の反響路で発生する音響エコーや、2線4線変換のハイブリッド回路において発生する回線エコーを抑圧するエコー抑圧処理技術、ハウリングを防止する音声スイッチ技術に関する。 The present invention echo path coupling estimation method and echo suppression method using the echo path coupling estimation method, the echo suppression process, the loss rate control method of the call path, the multi-channel echo suppressing method and these devices, a program, for example, acoustic echo and generated in the echo path of the hands-free speaker-phone call using a microphone and a speaker, an echo suppression processing technique for suppressing the line echo generated in the hybrid circuit of the two-wire four-wire conversion, a speech switch technique for preventing howling.

反響路(音響)結合量推定方法及び推定した反響路結合量を利用した反響消去装置に関する従来技術(特許文献1)について図6を用いて説明する。 For echo path (acoustic) coupling estimation methods and estimated echo path coupling amount prior art relating echo canceller using (Patent Document 1) is described with reference to FIG. 反響消去装置500は、反響消去部200と損失制御部300から成る。 Echo canceller 500 is comprised of a loss control unit 300 and the echo canceling unit 200. 損失制御部300内の損失量決定手段310が反響路結合量を推定し、その反響路結合量を元に損失量を決定する構成となっている。 Loss determining means 310 in the loss control unit 300 estimates the echo path binding amount, has a configuration that determines the amount of loss based on the echo path binding.
受話手段410(スピーカ)と送話手段420(マイクロホン)を用いたハンズフリー拡声通話を行う自分側を近端、通信路を挟んで通話を行う相手側を遠端とする。 Receiving means 410 (speaker) and microphone unit 420 proximal his side to perform hands-free speaker-phone call using the (microphone), and far-end an opponent making a call across a communications channel. 図6は、近端に配置された反響消去装置の処理を示している。 Figure 6 shows the process of the echo canceller arranged at the proximal end.

遠端の相手(話者)から通信路を経由して受信された受話信号x(n)が、受話手段410及び反響路を介して反響し、エコー信号y(n)として送話手段420に収音される場合を想定する。 Far-end party reception signal received via a communication path from the (speaker) x (n) is echoed through the receiving unit 410 and the echo path, the transmitter unit 420 as an echo signal y (n) it is assumed to be picked up.
反響消去部200では、受話信号x(n)と疑似反響路210から疑似エコー信号y^(n)を形成し、送話手段420に入力されたマイクロホン入力信号z(n)から差し引くことによりエコー信号y(n)を消去する。 The echo canceling unit 200, an echo by subtracting the received signal x (n) pseudo echo signal y ^ to form a (n) from the estimated echo path 210 from the input microphone input signal z to the transmitter unit 420 (n) erasing the signal y (n). マイクロホン入力信号z(n)は、通話状態によってエコー信号y(n)と送話信号s(n)のどちらか一方、もしくは両方で構成される。 Microphone input signal z (n), on the other hand either the echo signal y (n) of the transmission signal s (n) by the call state, or composed of both. ただし、受話信号x(n)がない場合には、同時にエコー信号y(n)が存在することはない。 However, when there is no received signal x (n) is never present echo signal y (n) at the same time.

推定手段220は、受話信号x(n)及び、マイクロホン入力信号z(n)から疑似エコー信号y^(n)を差し引いた後の誤差信号e(n)を用いて疑似反響路h^(n)を推定し、疑似反響路210を更新(修正)する。 Estimating means 220, the received signal x (n) and the pseudo from the microphone input signal z (n) echo signal y ^ estimated echo path by using the error signal e (n) after subtracting the (n) h ^ (n ) it was estimated, and updates the estimated echo path 210 (modified). 反響消去部200は、誤差信号e(n)及びマイクロホン入力信号z(n)を出力する。 Echo canceling unit 200 outputs an error signal e (n) and the microphone input signal z (n).
損失制御部300内の損失決定手段310には、受話信号x(n)、誤差信号e(n)及びマイクロホン入力信号z(n)が入力される。 The loss determination unit 310 in the loss control unit 300, the received signal x (n), the error signal e (n) and the microphone input signal z (n) is input. 損失量決定手段310では、はじめにダブルトーク状態の判定を行う。 In loss determining means 310, it is determined double-talk state in the beginning.

ダブルトーク状態とは、双方向で同時に通話を行う(つまり、相手側と自分側が一緒に発話する)状態であり、送話手段420にはエコー信号y(n)と送話信号s(n)が同時に入力(収音)される場合である。 The double-talk state, simultaneously call in both directions (i.e., speak together mating and self side) the state, the transmission unit 420 the echo signal y (n) and the transmission signal s (n) There is a case where the input (sound pickup) at the same time. 受話信号x(n)、入力信号z(n)、誤差信号e(n)の短時間パワーPx(n)、Pz(n)、Pe(n)をそれぞれ計算する。 Received signal x (n), the input signal z (n), short-time power Px of the error signal e (n) (n), Pz (n), calculates Pe (n) of each.
受話信号短時間パワーPx(n)が所定のしきい値xthを越え、1以下に設定されたしきい値Thとの間でPe(n)>Th×Pz(n)の関係が成り立てば、ダブルトーク状態ではないと判定する。 It received signal short-time power Px (n) exceeds a predetermined threshold value xth, if the relationship of Pe (n)> Th × Pz (n) between the set threshold Th 1 or less Naritate, It determined that it is not the double-talk state. またPx(n)>xthでかつPe(n)>Th×Pz(n)の関係が成り立てば、ダブルトーク状態か又は反響路が変化しているものと判定する。 Further it determines that if Naritate the relationship Px (n)> xth a and Pe (n)> Th × Pz (n), the double-talk state or the echo path is changing. 次に、ダブルトーク状態ではないと判定された場合に、Pz(n)/Px(n)から反響路結合量を求め、その逆数であるPx(n)/Pz(n)を損失量と決定する。 Then, if it is determined not to be the double talk state, obtains the echo path binding amount from Pz (n) / Px (n), its inverse Px (n) / Pz (n) of loss and determination to. 決定した損失量を損失量制御手段330に入力し、損失器10または損失器20によって、受話信号側又は送話信号側の少なくともどちらか一方に損失を挿入する。 Enter the determined loss in loss control means 330, by the loss 10 or loss 20, it inserts a loss for at least one of the received signal side or transmission signal side. これにより、遠端と近端を一巡する通信路(ループ)の利得(一巡増幅量)が1を超えハウリングが発生することを制御する。 Thus, the gain of the channel (loop) to cycle the far end and near end (round amplification amount) controls that howling exceed 1 occurs.
特許第3268572号明細書 Pat. No. 3268572

反響路結合量は、受話信号x(n)が反響路を経由してエコー信号y(n)となる際のパワー変化率であり、Py(n)/Px(n)の比に等しい。 Echo path coupling amount is a power change rate when the echo signal y (n) via the received signal x (n) is the echo path, equal to the ratio of Py (n) / Px (n). すなわち、送話手段420にエコー信号のみが入力されるシングルトーク状態と判別できれば、Py(n)とPx(n)が単独で測定可能なため反響路結合量は計算できる。 That is, if determined that the single-talk state in which only the echo signal to the transmitter unit 420 is input, Py (n) and Px (n) echo path coupling amount for measurable by itself can be calculated. しかし、この測定可能とする条件はシングルトーク状態の判別ができることが前提となる。 However, the conditions that allow the measurement is assumed to be able to discriminate single-talk state.
ダブルトーク状態の場合は、送話手段420にエコー信号だけではなく、送話信号s(n)も入力され、Py(n)が単独で測定できないために、反響路結合量の計算は不可能となる。 For double-talk state, not only the echo signal to the transmitter unit 420, transmission signal s (n) is also input, to Py (n) can not be measured alone, the echo path coupling weight calculations impossible to become.

従来方法においては、ダブルトーク状態でない(すなわち、シングルトーク状態である)場合を判定し、その時にのみ反響路結合量を決定する。 In the conventional method, not a double-talk state is determined (i.e., a is single talk state), to determine the echo path coupling amount only at that time. しかし、従来方法は、ダブルトークの判別にしきい値を用いているため、入力手段のゲイン設定や反響路の状態などの様々な環境において、いつも精度良く判別できる保証がない。 However, the conventional methods, the use of the threshold in determining the double-talk, in a variety of environments, such as the gain settings and echo path state of the input means, not always accurately determine be guaranteed. 加えて、ダブルトーク状態が続く場合には反響路結合量の計算が不可能となる。 In addition, it is impossible to calculate the echo path binding amount in the case of double-talk state is continued.
一方、受話信号が複数チャネルとされ、これらがそれぞれ音響として再生される場合は、1チャネルの方法をそのまま適用することはできない。 On the other hand, the received signal is a plurality of channels, they will when it is reproduced as sound, respectively, it can not be directly applied to the method of one channel. 具体的には、再生−収音の1対のモノラルチャネル毎で独立に音響結合量を推定することができない。 Specifically, the reproduction - it is impossible to estimate the acoustic coupling amount independently for each mono channel of a pair of sound collection. なぜなら、ひとつのマイクロホンには、複数のスピーカから複数のエコーが収音される。 This is because, in part of the microphone, a plurality of echoes from the plurality of speakers are picked up. 1対の再生−収音信号(1チャネル再生−1チャネル収音)でモノラルと同様な推定を行うと、対象とするスピーカ以外から拡声されたエコー分が加算されるため、見かけ上、音響結合量が大きく推定されてしまう。 A pair of regeneration - performed the same estimation and monaural sound collection signal (1 channel playback -1-channel sound), since the echo component that is loud from outside the speaker of interest is added, apparently, acoustic coupling the amount will be greatly estimated. そして推定誤差の影響によりエコー抑圧の性能劣化を引き起こす。 And cause deterioration of the performance of the echo suppression due to the influence of the estimation error.

本発明の目的は、ダブルトーク状態の判別が必要で、かつダブルトーク状態でも反響路結合量の推定が可能な反響路結合量推定方法及び装置、更に、この反響路結合量推定方法を用いたエコー抑圧方法及び装置、エコーサプレス方法及びエコーサプレッサ、通信路上の損失量制御方法及び装置、更には多チャネルエコー抑圧方法、多チャネルエコー抑圧装置を提案するものである。 An object of the present invention, requires discrimination of double-talk state, and echo path which can be estimated echo path coupling amount in the double-talk state coupling estimation method and apparatus, furthermore, using the echo path coupling estimation method echo suppressing method and apparatus, the echo suppression process and the echo suppressor, the communication path loss control method and apparatus, and more is to propose a multi-channel echo suppressing method, the multi-channel echo suppressor.

この発明では受話端と送話端間の反響路結合量を推定する反響路結合量推定方法において、受話信号を周波数領域に変換し、受話信号の周波数係数から各周波数帯域毎の受話信号パワーを計算する処理と、送話信号に反響路を経由した反響信号が加算された入力信号を周波数領域に変換し、入力信号の周波数係数から各周波数帯域毎の入力信号パワーを計算する処理と、受話信号パワーに対する入力信号パワーのパワー比を各周波数帯域別に計算する処理と、各周波数帯域毎に計算したパワー比の最小値を更新し、各周波数帯域毎のパワー比の更新した最小値を保持し、各周波数帯域毎に保持された最小パワー比を各周波数帯域別の反響路結合量として出力する処理とを含むことを特徴とする反響路結合量推定方法を提案する。 In echo path coupling estimation method for estimating the echo path coupling amount between the transmitting end and the receiving end in the present invention, converts the received signal into the frequency domain, the received signal power for each frequency band from the frequency coefficients of the received signal a process of calculations, a process of echo signals via the echo path into transmission signal converts the input signal added to the frequency domain to calculate the input signal power for each frequency band from the frequency coefficients of an input signal, a receiver update processing for calculating the power ratio of the input signal power to signal power for each frequency band, the minimum value of the calculated power ratio for each frequency band, and holds the minimum value updated power ratios for each frequency band proposes the echo path coupling estimation method characterized by comprising a process of outputting the minimum power ratio held for each frequency band as a separate echo path coupling amount each frequency band.

この発明では上記した反響路結合量推定方法において、各周波数帯域別の反響路結合量の内の最大値を周波数帯域一括の反響路結合量として出力することを特徴とする反響路結合量推定方法を提案する。 In echo path coupling estimation method described above in the present invention, the echo path coupling estimation method and outputs the maximum value among the respective frequency bands by the echo path coupling amount as echo path coupling of the frequency bands simultaneously Suggest.
この発明では受話端と送話端間の反響路結合量を推定する反響路結合量推定装置において、受話信号を周波数係数に変換する第1周波数分析手段と、この第1周波数分析手段で分析した受話信号の周波数係数から各周波数帯域毎の受話信号パワーを計算する第1帯域別パワー計算手段と、送話信号に反響路を経由した反響信号が加算された入力信号を周波数係数に変換する第2周波数分析手段と、この第2周波数分析手段で分析した入力信号の周波数係数から各周波数帯域毎の入力信号のパワーを計算する第2帯域別パワー計算手段と、受話信号パワーに対する入力信号パワーのパワー比を各周波数帯域別に計算する第2帯域別パワー比計算手段と、各周波数帯域別に計算したパワー比の最小値を更新し、各周波数帯域別のパワー比の更新し In echo path coupling estimation device for estimating the echo path coupling amount between the transmitting end and the receiving end in the present invention, the first frequency analyzing means for converting a received signal into a frequency coefficient, and analyzed by the first frequency analysis means the converting a first band-by-band power calculating means for calculating a received signal power for each frequency band from the frequency coefficients of the received signal, an input signal echo signal is added passing through the echo path in the transmission signal into a frequency coefficient and second frequency analysis means, and a second band-dependent power calculating means for calculating the power of the input signal for each frequency band from the frequency coefficients of the input signal analyzed by the second frequency analysis means, the input signal power for the received signal power a second band-dependent power ratio calculating means for calculating a power ratio for each frequency band, and updates the minimum value of the calculated power ratio for each frequency band, updating of each frequency band different power ratio 最小値を保持し、各周波数帯域別に保持された最小パワー比を各周波数帯域別の反響路結合量として各周波数帯域別に計算したパワー比の最小値を更新し、各周波数帯域別に保持された最小パワー比を各周波数帯域別の反響路結合量として出力する帯域別パワー比最小値保持手段とを備えることを特徴とする反響路結合量推定装置を提案する。 Minimum for holding the minimum value, the minimum power ratio held for each frequency band to update the minimum value of the power ratio calculated for each frequency band as a separate echo path coupling amount each frequency band, which is held for each frequency band Suggest echo path coupling estimation device characterized by comprising a band-dependent power ratio minimum value holding means for outputting a power ratio as a separate echo path coupling amount each frequency band.

この発明では更に、上記した反響路結合量推定装置において、帯域別パワー比最小値保持手段が出力する各周波数帯域別のパワー比最小値の内からパワー比の最大値を抽出し、このパワー比最小値の内から抽出したパワー比の最大値を帯域一括反響路結合量として出力する帯域一括反響路結合量計算手段を備えることを特徴とする反響路結合量推定装置を提案する。 Furthermore, in this invention, in the echo path coupling estimation apparatus described above, it extracts the maximum value of the power ratio from among the each frequency band of the power ratio minimum band-dependent power ratio minimum value holding means outputs, the power ratio Suggest echo path coupling estimation device characterized by comprising a band collective echo path coupling amount calculating means for outputting as a band collectively echo path coupling amount the maximum value of the extracted power ratio among the minimum value.
この発明では更に、コンピュータが解読可能なプログラム言語によって記述され、コンピュータを上記反響路結合量推定装置の何れかとして機能させる反響路結合量推定プログラムを提案する。 Furthermore, in this invention, a computer is described by a readable programming language, the computer proposes echo path coupling estimation program to function as either the echo path coupling estimation device.

この発明では更に、受話信号を周波数領域に変換し、受話信号の周波数係数から各周波数帯域毎の受話信号パワーを計算する処理と、送話信号に反響路を経由した反響信号が加算された入力信号を周波数領域に変換し、入力信号の周波数係数から各周波数帯域毎の入力信号パワーを計算する処理と、受話信号パワーに対する入力信号パワーのパワー比を各周波数帯域別に計算する処理と、各周波数帯域毎に計算したパワー比の最小値を更新し、各周波数帯域毎のパワー比の更新した最小値を保持し、各周波数帯域毎に保持された最小パワー比を各周波数帯域別の反響路結合量として出力する処理とを含む反響路結合量推定方法で計算した帯域別反響路結合量に受話信号を周波数分析して求めた帯域別受話信号パワーを重畳して、帯域別エコー Furthermore, in the present invention, converts the received signal into the frequency domain, the process of calculating the received signal power for each frequency band from the frequency coefficients of the received signal, echo signals via the echo path into transmission signal is added input converts the signal into the frequency domain, the frequency coefficients of an input signal and a process of calculating an input signal power for each frequency band, a process of calculating the power ratio of the input signal power for each frequency band for the received signal power, the frequency update the minimum value of the calculated power ratio for each band, and holds the minimum value updated power ratios for each frequency band, the minimum power ratio each frequency band different echo path coupling a retained for each frequency band by superimposing the band-by-band received signal power obtained by frequency analysis of the received signal to the band-by-band echo path coupled amount calculated by the echo path coupling estimation method comprising a process of outputting an amount, per-band echo 号パワーを計算し、送話信号に反響路を経由した反響信号が加算された入力信号を周波数分析して求めた帯域別入力信号パワーと帯域別エコー信号パワーの比により各周波数帯域別の抑圧ゲインを求め、入力信号周波数係数の振幅成分に抑圧ゲインを重畳し、周波数帯域別にエコー信号を抑圧し、エコー信号を抑圧処理した周波数係数を合成し、エコー信号を抑圧した時間信号を出力することを特徴とするエコー抑圧方法を提案する。 No. power is calculated and the suppression of by each frequency band by the ratio of the band-by-band input signal power and the per-band echo signal power echo signal is determined by frequency analysis of the input signal added to via the echo path into transmission signal seeking gain superimposes the suppression gain to the amplitude component of the input signal frequency coefficients, an echo signal is suppressed for each frequency band, to synthesize the echo signal suppression processing and frequency coefficients, and outputs a time signal has been suppressed echo signals that Suggest echo suppressing method according to claim.

この発明では更に、受話信号を周波数係数に変換する第1周波数分析手段と、この第1周波数分析手段で分析した受話信号の周波数係数から各周波数帯域毎の受話信号パワーを計算する第1帯域別パワー計算手段と、送話信号に反響路を経由した反響信号が加算された入力信号を周波数係数に変換する第2周波数分析手段と、この第2周波数分析手段で分析した入力信号の周波数係数から各周波数帯域毎の入力信号のパワーを計算する第2帯域別パワー計算手段と、上記受話信号パワーに対する上記入力信号パワーのパワー比を各周波数帯域別に計算する第2帯域別パワー比計算手段と、各周波数帯域別に計算したパワー比の最小値を更新し、各周波数帯域別のパワー比の更新した最小値を保持し、各周波数帯域別に保持された最小パワー比 Furthermore, in the present invention, the first frequency analyzing means for converting a received signal into frequency coefficients, a first band-by-band to calculate the received signal power for each frequency band from the frequency coefficients of the received signals analyzed by the first frequency analysis means a power calculation means, an input signal echo signal is added passing through the echo path in the transmission signal and the second frequency analysis means for converting the frequency coefficients from the frequency coefficients of the input signal analyzed by the second frequency analysis means a second band-by-band power calculating means for calculating the power of the input signal for each frequency band, a second band-dependent power ratio calculating means for calculating a power ratio of the input signal power for each frequency band for the received signal power, It updates the minimum value of the power ratio calculated for each frequency band, the minimum power ratio that holds the minimum value updated for each frequency band by the power ratio, which is held for each frequency band 各周波数帯域別の反響路結合量として各周波数帯域別に計算したパワー比の最小値を更新し、各周波数帯域別に保持された最小パワー比を各周波数帯域別の反響路結合量として出力する帯域別パワー比最小値保持手段とによって構成した反響路結合量推定装置を備え、 Update the minimum value of the power ratio calculated for each frequency band as each frequency band different echo path coupling amount, per band to output the minimum power ratio held for each frequency band as a separate echo path coupling amount each frequency band includes a echo path coupling estimation device configured by the minimum value holding means power ratio,
この反響路結合量推定装置で計算した帯域別反響路結合量に、受話信号を周波数分析して求めた帯域別受話信号パワーを重畳し、帯域別エコー信号パワーを計算する帯域別エコー信号パワー計算手段と、送話信号に反響路を経由した反響信号が加算された入力信号を周波数領域に周波数分析して求めた帯域別入力信号パワーと、上記帯域別エコー信号パワー計算手段で計算した帯域別エコー信号との比によって周波数帯域別のエコー抑圧ゲインを求める抑圧ゲイン計算手段と、この抑圧ゲイン計算手段で計算した周波数帯域別のエコー抑圧ゲインと上記入力信号の周波数係数とを重畳し、各周波数帯域別にエコーを抑圧するエコー抑圧手段と、エコー抑圧手段でエコーが抑圧された周波数係数を合成し、時間信号に合成する時間信号合成手段 A band-by-band echo path coupled amount calculated in this echo path coupling estimation device superimposes the band-by-band received signal power obtained by frequency analysis of the received signal, band-by-band echo signal power calculation for calculating per-band echo signal power means and the band-by-band input signal power obtained by frequency analyzing the input signal echo signal is added passing through the echo path in the frequency domain transmission signal, the band-by-band computed in the band-by-band echo signal power calculation means superimposing a suppression gain calculating means for calculating a frequency band different echo suppression gain by the ratio of the echo signal, the frequency coefficients of the alternative frequency bands calculated by the suppression gain computing unit echo suppression gain and said input signal, each frequency an echo suppression means for suppressing an echo by the band, time signal synthesizing means for synthesizing the frequency coefficients echo is suppressed by the echo suppression means for synthesizing the time signals によって構成されるエコー抑圧装置を提案する。 I suggest composed echo suppressor by.

この発明では更に、コンピュータが解読可能なプログラム言語によって記述され、コンピュータを上記エコー抑圧装置として機能させるエコー抑圧プログラムを提案する。 Furthermore, in this invention, a computer is described by a readable programming language, the computer proposes echo suppressing program to function as the echo suppressor.
この発明では更に、受話信号のパワーを計算し、この受話信号パワーに上記反響路結合量推定手段で計算した周波数帯域一括の反響路結合量を乗算し、その逆数を求めて損失量を求め、この損失量を送話信号に反響路を経由した反響信号が加算された入力信号に乗算し、入力信号に含まれるエコー信号を抑圧することを特徴とするエコーサプレス方法を提案する。 Furthermore, in this invention, to calculate the power of the received signal, the received signal power by multiplying the echo path coupling of the frequency band simultaneously calculated above echo path coupling estimation means obtains a loss seeking its reciprocal, the loss amount by multiplying the input signal echo signals via is added to the echo path in the transmission signal a new echo suppression method characterized by suppressing an echo signal contained in the input signal.

この発明では更に、受話信号のパワーを計算する受話信号パワー計算手段と、上記反響路結合量推定装置で計算した周波数帯域一括の反響路結合量と受話信号パワー計算部で計算した受話信号パワーとを乗算し、その逆数を損失量として求める損失量計算手段と、この損失量計算部で計数した損失量をマイクロホン入力信号に乗算してエコー信号を抑圧した信号として出力する損失手段とによって構成したエコーサプレッサを提案する。 Furthermore, in the present invention, the received signal power calculating means for calculating a power of the reception signal, and the reception signal power calculated in the echo path coupling amount and the reception signal power calculating portion of the frequency band simultaneously calculated above echo path coupling estimation apparatus multiplied by a loss amount calculation means for calculating the inverse as loss, was constructed by the loss means for outputting a loss counted in this loss calculator as a signal obtained by suppressing the echo signal by multiplying the microphone input signal to propose an echo suppressor.
この発明では更に、コンピュータが解読可能なプログラム言語によって記述され、コンピュータを上記エコーサプレッサとして機能させるエコーサプレッサプログラムを提案する。 Furthermore, in this invention, a computer is described by a readable programming language, the computer proposes echo suppressor program to function as the echo suppressor.

この発明では更に、上記反響路結合量推定方法で計算した帯域一括反響路結合量から通信ループに挿入すべき損失量を計算し、計算された損失量に従って通信路に挿入した損失器の損失量を制御する通信路上の損失量制御方法を提案する。 Furthermore, in this invention, the amount of loss to be inserted into the communication loop from the band collectively echo path binding amount calculated above echo path coupling estimation method to calculate the loss of inserted loss device to the communication channel according to the calculated loss Suggest loss control method of a communication path for controlling.
この発明では更に、上記反響路結合量推定装置で計算された帯域一括音響結合量から通信ループに挿入すべき損失量を計算する損失量計算手段と、この損失量計算手段で計算した損失量を受話側又は送話側に挿入すべきかを決定し、その決定に従って受話側及び送話側に挿入した損失器の何れかの損失量を制御する損失制御手段とを備える通信路上の損失制御装置を提案する。 Furthermore, in the present invention, the loss amount calculation means for calculating the amount of loss to be inserted into the communication loop from the band collectively acoustic coupling amount calculated by the echo path coupling estimation apparatus, the loss amount calculated in this loss calculation means determine to be inserted into the receiving side or the transmitting side, loss control device on the communication path and a loss control means for controlling one of loss of loss instrument inserted into the receiving side and the transmitting side according to the determined suggest.

この発明では更に、コンピュータが解読可能なプログラム言語によって記述され、コンピュータ上記通信路上の損失制御装置として機能させる通話路上の損失制御プログラムを提案する。 Furthermore, in this invention, a computer is described by a readable programming language, we propose a loss control program calls path to function as loss control device of the computer the communication path.
この発明では更に、Nチャネル(N>1)の受話信号を再生し、Mチャネル(M>1)の入力信号を収音する場合に発生する複数エコーを抑圧する多チャネルエコー抑圧方法であって、Nチャネルの受話信号を加算した加算受話信号と、M個の入力信号それぞれを用いて上記エコー抑圧方法でそれぞれMチャネル毎にエコーを抑圧することを特徴とする多チャネルエコー抑圧方法を提案する。 Furthermore, in the present invention reproduces the received signal of the N-channel (N> 1), a multi-channel echo suppressing method for suppressing multiple echoes occur when picking up an input signal of the M-channel (M> 1) proposes an addition reception signal obtained by adding the received signals of N channels, a multi-channel echo suppression method characterized by suppressing an echo every M channels, respectively the echo suppressing method using each M input signals .

この発明では更に、Nチャネル(N>1)の受話信号を再生し、Mチャネル(M>1)の入力信号を収音する場合に発生する複数エコーを抑圧する多チャネルエコー抑圧装置であって、Nチャネルの受話信号を加算する加算器と、この加算器で加算した加算受話信号とM個の入力信号それぞれを用いてMチャネル毎のそれぞれのエコーを抑圧する上記エコー抑圧装置によって構成される多チャネルエコー抑圧装置を提案する。 Furthermore, in the present invention reproduces the received signal of the N-channel (N> 1), a multi-channel echo suppressor for suppressing multiple echoes occur when picking up an input signal of the M-channel (M> 1) an adder for adding the reception signal of the N-channel constituted by the echo suppressor for suppressing respective echo every M channels with each sum the received signal and the M input signals added by the adder we propose a multi-channel echo suppressor.
この発明では更に、コンピュータが解読可能なプログラム言語によって記述され、コンピュータを上記多チャネルエコー抑圧装置として機能させる多チャネルエコー抑圧プログラムを提案する。 Furthermore, in this invention, a computer is described by a readable programming language, the computer proposes a multi-channel echo suppression program to function as the multi-channel echo suppressor.

この発明では更に、コンピュータが読み取り可能な記録媒体で構成され、この記録媒体に少なくとも上記反響路結合量推定プログラム、又は上記エコー抑圧プログラム、或は上記エコーサプレッサプログラム、上記通信路上の損失制御プログラム、上記多チャネルエコー抑圧プログラムの何れかを記録した記録媒体を提案する。 Furthermore, in this invention, a computer is composed of a recording medium readable, at least the echo path coupling estimation program on this recording medium, or the echo suppressing program, or the echo suppressor program, loss control program of the communication path, We propose a recording medium recording any of the above multi-channel echo suppression program.

本発明の反響路結合量推定方法によればダブルトーク状態の判別が不要で、かつダブルトーク状態でも反響路結合量の推定が可能となる。 Not necessary to distinguish double-talk state according to the echo path coupling estimation method of the present invention, and it is possible to estimate the echo path coupling amount in a double talk state. 従って、この発明の反響路結合量推定方法をエコー抑圧技術、エコーサプレス技術及びハウリング発生を抑制するための通信路上の損失制御技術に応用することにより、ダブルトーク状態が長く続いても、制御状態が維持されエコー抑圧状態及びハウリングの抑制状態を安定に維持することができる。 Therefore, echo path coupling estimation methods echo suppression technique of the present invention, by applying to the loss control technology of the communication path to suppress echo suppression techniques and howling occurs, even if the double talk state is continued for a long time, the control state There the suppression state of being maintained echo suppression state and howling can be stably maintained.
更に、本発明による多チャネルエコー抑圧方法及び装置によれば、複数の再生信号を加算して、仮想的にモノラルの信号にして先のモノラルで提案した方法で音響結合量を推定する。 Furthermore, according to the multi-channel echo suppressing method and apparatus according to the present invention, by adding a plurality of reproduction signals, to estimate the acoustic coupling amount proposed method in the virtually mono signal in the previous mono. 次に、エコー抑圧に関しても、複数の再生信号を加算して抑圧ゲインを計算してエコー抑圧処理を行う。 Next, with respect to the echo suppression, performing echo suppression process by calculating a suppression gain by adding a plurality of reproduced signals. これにより、スピーカとマイクロホン間の複数のエコー経路の音響結合量を独自に求めることなく、複数のスピーカ全てに対する1つのマイクロホンの音響結合量を推定し、その値を用いてエコー抑圧することが可能となる。 Thus, no uniquely determine that the acoustic coupling of a plurality of echo path between the loudspeaker and the microphone, estimating the acoustic coupling of one microphone for all of the plurality of speakers, can be echo suppression using the value to become.

本発明による反響路結合量推定装置、エコー抑圧装置、エコーサプレッサ、通信路上の損失量制御装置は専用のハードウェアを組み立てて実現することも可能であるが、一般的には本発明で提案する反響路結合量推定プログラム、エコー抑圧プログラム、エコーサプレッサプログラム、通信路上の損失量制御プログラムをコンピュータにインストールし、インストールした各プログラムをコンピュータに備えたCPU(中央演算処理装置)に解読させ、実行させることにより実現する実施形態が最良の形態である。 Echo path coupling estimation apparatus according to the present invention, the echo suppressor, an echo suppressor, although loss control device of the communication path it is also possible to realize assembling a dedicated hardware, typically proposed in the present invention echo path coupling estimation program, echo suppression program, install echo suppressor program, the communication path loss amount control program in the computer, is decrypted to the CPU with each program installed in a computer (central processing unit) to execute embodiments realized by is the best form.

図1及び図2を用いてこの発明の第1実施例を説明する。 Explaining the first embodiment of the present invention with reference to FIGS. この第1実施例では本発明の請求項3で提案する反響路結合量推定装置及び請求項6で提案するエコー抑圧方法を実現するための請求項7で提案するエコー抑圧装置の実施例を示す。 It shows an embodiment of the echo suppressing apparatus proposed in claim 7 for realizing the echo suppression method proposed in the echo path coupling estimation apparatus and claim 6 proposed in claim 3 of the present invention in this first embodiment .
受話手段410(スピーカ)と送話手段420(マイクロホン)を用いたハンズフリー拡声通話を行う自分側を近端、通話路を挟んで通話を行う相手側を遠端とする。 Receiving means 410 (speaker) and microphone unit 420 proximal his side to perform hands-free speaker-phone call using the (microphone), and far-end an opponent making a call across the communication path. 図1は近端に配置されたエコー抑圧装置301の処理を示している。 Figure 1 shows the process of the echo suppressor 301 disposed near end.
送話手段420には、遠端の相手(話者)から通話路を経由して受信された受話信号x(n)が、受話手段410及び反響路を介して反響したエコー信号y(n)もしくは送話信号s(n)のどちらか一方、もしくは両方(ダブルトーク状態)が入力(収音)されマイクロホン入力信号z(n)となる。 The transmission means 420, the far end of the other party received signal received via the speech path from the (speaker) x (n) is, the echo signal y echoed through the receiving means 410 and echo path (n) or either one of the transmission signal s (n), or the both (double talk state) input (sound pickup) to the microphone input signal z (n). 尚、受話信号x(n)がない場合には、同時にエコー信号y(n)が存在することはない。 Incidentally, when there is no received signal x (n) is never present echo signal y (n) at the same time. 反響路結合量推定装置100は、ダブルトーク状態かどうかの如何に関わらず以下の処理により反響路結合量を推定する。 Echo path coupling estimation apparatus 100 estimates the echo path coupling amount by the following process regardless of whether a double-talk state.

反響路結合量推定装置100には、受話信号x(n)及びマイクロホン入力信号z(n)を入力する。 The echo path coupling estimation apparatus 100, inputs the received signal x (n) and the microphone input signal z (n).
受話信号側の周波数分析手段110で時間信号である受話信号x(n)をフレ−ムに切り取り周波数領域に変換して各周波数帯域を分割し、受話信号周波数係数X(m,f)を出力する。 Frame the reception signal x (n) is a time signal with a frequency analysis means 110 of the receiving signal side - is converted into cut frequency domain beam dividing each frequency band, the received signal frequency coefficients X (m, f) the output to. ここで、mは現行フレームの番号、fは周波数領域の各帯域を示す番号(周波数)を表す。 Here, m is the number of the current frame, f is representative of the number (frequency) showing each band in the frequency domain.
受話信号側の帯域別パワー計算手段130で受話信号周波数係数X(m,f)から帯域別受話信号パワーPX(m,f)を計算する。 Received signal frequency coefficient in a band-dependent power calculation unit 130 of the reception signal side X (m, f) the band-by-band received signal from the power PX (m, f) is calculated.

マイクロホン入力信号側の周波数分析手段120で入力信号z(n)を周波数領域に変換し、入力信号周波数係数Z(m,f)を出力する。 Converting the input signal z (n) to the frequency domain by the frequency analysis means 120 of the microphone input signal side, and outputs the input signal frequency coefficient Z (m, f).
マイクロホン入力信号側の帯域別パワー計算手段140で入力信号周波数係数Z(m,f)から帯域別入力信号パワーPZ(m,f)を計算する。 Input signal frequency coefficient Z in the band-dependent power calculation unit 140 of the microphone input signal side (m, f) the band-by-band input signal from the power PZ (m, f) is calculated.
帯域別パワー比計算手段150で、各帯域でそれぞれPZ(m,f)/PX(m,f)のパワー比を計算し、帯域別パワー比A(m,f)を出力する。 In the band-by-band power ratio calculating means 150, a power ratio calculated for each in each band PZ (m, f) / PX (m, f), and outputs the band-dependent power ratio A (m, f).
帯域別パワー比最小値保持手段160では、入力された帯域別パワー比A(m,f)と保持されている最小帯域別パワー比C(m―1,f)と比較する。 In the band-by-band power ratio minimum value holding means 160, for comparing the input per-band power ratio A (m, f) and the minimum band-by-band power ratio C held the (m-1, f). A(m,f)<C(m―1,f)の場合には、最小値を更新してC(m,f)=A(m,f)として保持する。 In the case of A (m, f) <C (m-1, f) and holds updating the minimum value as C (m, f) = A (m, f). A(m,f)>C(m―1,f)の場合には、最小値を更新せず、C(m,f)=C(m―1,f)として保持する。 In the case of A (m, f)> C (m-1, f) does not update the minimum value is retained as C (m, f) = C (m-1, f). そして保持された最小帯域別パワー比C(m,f)を周波数帯域別反響路結合量として出力する。 The minimum bandwidth dependent power ratio C (m, f), which is held to be output as each frequency band echo path binding.

ここで、帯域別パワー比計算手段150と帯域別パワー比最小値保持手段160の行う処理の原理を説明する。 Here, to explain the principles of the processing performed by the band-by-band power ratio calculating means 150 and the band-dependent power ratio minimum value holding means 160. エコー信号と送話音声は、異なる話者の音声のために周波数特性(声紋)が異なる。 Echo signal and transmitted voice, the frequency characteristics for different speakers voice (voiceprint) is different. 具体的には、音声の調波構造(周波数軸上のピーク値)が同じ位置になることはほぼない(各音声信号の間にスパース性という特徴があるため)。 Specifically, (because of the characteristic of sparseness between each audio signal) substantially not that the voice of the harmonic structure (peak value on the frequency axis) in the same position. すなわち、ダブルトーク状態であっても、受話信号パワーのピークのある帯域には、受話信号が反響して生成したエコー信号パワーのピークのみが存在し、送話信号パワーのピークは存在しない。 That is, even double-talk state, the band of the peak of the received signal power, only the peak of the echo signal power received signal that was generated by echo exists, the peak of the transmission signal power is not present. そのために、受話信号のピークの存在する帯域だけで帯域別パワー比を計算すれば、受話信号パワーに対するエコー信号パワーの比、すなわちその帯域の反響路結合量を特定するこてができる。 Therefore, by calculating per-band power ratio only band present in peak of the received signal, the ratio of the echo signal power for the received signal power, that can trowel to identify the echo path coupling of the band.

受話信号パワーのピークがなく(レベルが小さく)、送話信号パワーのピークがある場合は、その帯域別パワー比は大きくなり、真の反響路結合量を求めることはできない。 No peak of the received signal power (level is small), if there is a peak of the transmission signal power, the band-dependent power ratio becomes large, it is impossible to determine the true echo path binding. しかし、時間と共に受話信号の周波数特性(ピーク位置)は変動する(例えば、通常の会話で発声する母音が異なる)ので、上記フレーム処理を何度か行い帯域別のパワーの最小値を更新して保持することにより、各帯域全ての反響路結合量を推定することができる。 However, the frequency characteristic of the received signal (peak position) with time varies (e.g., vowels are different uttered in normal conversation) so, updates the minimum value of the several performed per-band power of the frame processing by holding, it is possible to estimate the respective bands all echo path binding.
以上によって推定した帯域別の反響路結合量C(m,f)をエコー抑圧部600に入力する。 The estimated per-band echo path coupling amount C (m, f) is input to the echo suppressor 600 by the above.

エコー抑圧部600は図2に示すように帯域別エコー信号パワー計算手段601と、抑圧ゲイン計算手段602と、ゲイン制御手段603とを具備し、帯域別エコーパワー信号計算手段601では帯域別反響路結合量C(m,f)に加えて帯域別パワー計算手段130から受話信号x(n)の帯域別受話信号パワーPX(m,f)を取り込み、帯域別受話信号パワーPX(m,f)に帯域別反響路結合量C(m,f)を重畳し、帯域別エコー信号パワーPE(m,f)を計算し、抑圧ゲイン計算手段602にこの帯域別信号パワーPE(m,f)を入力する。 Echo suppressing unit 600 and the band-by-band echo signal power calculation means 601 as shown in FIG. 2, a suppression gain calculating unit 602, includes a gain control unit 603, the band-by-band echo path in band-by-band echo-power signal calculating means 601 binding amount C (m, f) from the band-by-band power calculation unit 130 in addition to the capture per-band received signal power PX of the received signal x (n) (m, f), the band-by-band received signal power PX (m, f) a band-by-band echo path coupling amount C (m, f) superimposing the band by the echo signal power PE (m, f) calculate the, the band-by-band signal power PE to the suppression gain computing unit 602 (m, f) input. これと共に、抑圧ゲイン計算手段602では帯域別パワー計算手段140から帯域別入力信号パワーPZ(m,f)を取り込み、帯域別入力信号パワーPZ(m,f)に対する帯域別エコー信号パワーPE(m,f)の比(PE(m,f)/PZ(m,f))を1から差し引いた値である1−(PE(m,f)/PZ(m,f))で決められる抑圧ゲインを求める。 At the same time, the suppression gain calculating unit 602 in the band-by-band power calculating unit 140 from the band-by-band input signal power PZ (m, f) uptake, the band-by-band input signal power PZ (m, f) the band-by-band echo signal to the power PE (m the ratio (PE (m, f) of f) / PZ (m, f)) is a value obtained by subtracting from 1 1- (PE (m, f) / PZ (m, f) suppression gain that is determined by) the seek.

抑圧ゲイン計算手段602で求められた抑圧ゲインはゲイン制御手段603に入力される。 Suppression gain obtained in suppression gain calculating unit 602 is input to the gain control unit 603. ゲイン制御手段603では周波数分析手段120から入力信号周波数係数Z(m,f)を取り込み、入力信号周波数係数Z(m,f)の振幅成分に抑圧ゲインを重畳し、周波数帯域別にエコー信号を抑圧する。 Input signal frequency coefficient from the gain control unit 603 in the frequency analysis means 120 Z (m, f) uptake, superimposes the suppression gain to the amplitude component of the input signal frequency coefficient Z (m, f), suppresses the echo signal for each frequency band to.
周波数帯域別にエコー信号を抑圧した入力信号周波数係数Z(m,f)を時間信号合成部700(図1)に入力し、この時間信号合成部700で周波数係数を合成(逆変換)してエコー信号を抑圧した処理後の時間信号として出力する。 Input signal frequency coefficient Z which has been suppressed echo signals for each frequency band (m, f) inputted to the time signal combining unit 700 (FIG. 1), echo frequency coefficients synthesized (reverse conversion) at which time the signal combining unit 700 and outputs as the time signal after processing suppressed signal.

図1に示したエコー抑圧装置301によれば反響路結合量推定装置100で推定した反響路結合量C(m,f)を用いるため、ダブルトーク状態でも反響路結合量C(m,f)を得ることができる。 Since the use of echo path coupling amount estimated in the echo path coupling estimation device 100 according to the echo suppressor 301 shown in FIG. 1 C (m, f), the amount of echo path coupled in double talk state C (m, f) it is possible to obtain. この結果、仮にダブルトーク状態が長く続いていたとしても、エコー抑圧状態を安定して維持することができる利点が得られる。 As a result, even if the double talk state has been continued for a long time, the advantage of being able to maintain the echo suppression state stably obtained.
尚、上述したエコー抑圧処理は周波数領域でエコー抑圧処理が行われており、ここではこの方式のエコー抑圧処理をエコー抑圧処理、エコー抑圧装置等と称すことにする。 Incidentally, an echo suppression process described above is performed echo suppression processing in the frequency domain, wherein the echo suppression process the echo suppression process of this type, will be referred to as echo suppression device. これに対し、以下に説明する時間領域でエコー抑圧処理を行う方式をここではエコーサプレス方法乃至はエコーサプレッサと称すことにする。 In contrast, here the method of performing an echo suppression processing in the time domain as described below or echo suppression methods will be referred to as an echo suppressor.

実施例2ではこの発明の主要部となる反響路結合量推定装置と、請求項10で提案するエコーサプレッサの実施例を示す。 And the main part echo path coupling estimation apparatus of the second embodiment in the present invention, illustrating an embodiment of an echo suppressor proposed in claim 10. この実施例2でも反響路結合量推定装置100の構成及びその動作は実施例1と同じであるから、ここではその重複説明は省略するが、この実施例では反響路結合量推定装置100の出力側に帯域一括反響路結合量計算部800が設けられる。 Since this configuration and operation of the echo path coupling estimation apparatus 100 in Embodiment 2 are the same as in Example 1, where the is omitted, duplicate description, the output of the echo path coupling estimation apparatus 100 in this embodiment band collective echo path coupling amount calculation unit 800 is provided on the side.
帯域一括反響路結合量計算部800は各帯域にそれぞれの反響路結合量C(m,f)のうち最大値を全ての帯域を一括して代表した反響路結合量C(n)として出力する処理を実行する。 Band collective echo path coupling amount calculation unit 800 outputs as collectively representing the echo path coupling amount C (n) of all bands to the maximum value of the respective echo path coupling amount C (m, f) in each band process to run.

ここで、各帯域毎に計算した反響路結合量C(m,f)のうち最大値を全ての帯域を一括して代表した反響路結合量C(n)とした理由は、以下で説明するエコーサプレッサにおける反響路の最悪条件下(最大結合状態にある帯域)でのエコーを抑圧することに整合させるためである。 Here, the reason for each band echo path binding amount was calculated for each C (m, f) echo path binding amount was represented collectively all band the maximum value of C (n) are described below is to match the suppressing an echo in the worst case the echo path (band in the maximum coupling state) in the echo suppressor.
図3では受話端に入力される受話信号x(n)と、送話手段420から出力されるマイクロホン入力信号z(n)はそれぞれ、図1の場合と異なり周波数分析手段110及び120を介することなく受話端から直接受話手段410に入力され、また送話手段420から損失器20を通じて出力される。 The received signal x (n) which is input to the reception terminal 3, respectively microphone input signal z (n) is output from the transmitter unit 420, passing through the frequency analysis means 110 and 120 different from the case of FIG. 1 without directly input to the receiver unit 410 from the receiving end, also is output through loss 20 from transmitter unit 420. これにより、受話端から受話手段410に至る間の信号及び送話手段420から損失器20を通じて出力される信号が時間領域の信号であり、エコーサプレッサ302が時間領域でエコー抑圧動作を行っていることを意味している。 Thereby, a signal and the signal is a time domain signal output through loss 20 from transmission means 420 between extending from the receiving end to the receiving means 410, the echo suppressor 302 is performing echo suppression operation in the time domain which means that.

受話信号パワー計算部820に受話信号x(n)を入力し、サンプリング時間n毎の受話信号パワーPx(n)を計算し、出力する。 The received signal power calculation unit 820 inputs the reception signal x (n), calculates the received signal power Px at each sampling time n (n), and outputs.
損失量計算部810には、帯域一括反響路結合量c(n)と受話信号パワーPx(n)を入力する。 The loss calculation section 810, and inputs the band collectively echo path coupling amount c (n) and the received signal power Px (n). そして、帯域一括反響路結合量c(n)と受話信号パワーPx(n)を掛け合わせたパワーの逆数を損失量M(n)とする。 Then, the inverse of the power obtained by multiplying the band collectively echo path coupling amount c (n) the received signal power Px (n) and the loss M (n).
損失器20には、損失量M(n)とマイクロホン入力信号z(n)が入力され、マイクロホン入力信号z(n)に損失量M(n)を乗じた値を出力する。 The loss 20, is input loss M (n) and the microphone input signal z (n) outputs a value obtained by multiplying the loss M (n) to a microphone input signal z (n).

エコーサプレッサ302の原理を以下に説明する。 To explain the principles of the echo suppressor 302 below. 損失量計算部810において、帯域一括反響路結合量c(n)と受話信号パワーPx(n)を掛け合わせた値は、エコー信号のパワーPy(n)に等しい。 In the loss amount calculation unit 810, a value obtained by multiplying the band collectively echo path coupling amount c (n) and the received signal power Px (n) is equal to the power Py (n) of the echo signal. なぜなら、受話信号x(n)は反響路を介してエコー信号y(n)となり、その際のパワー変動(最大もしくは減少)は、反響路結合量c(n)に比例するためである。 This is because the received signal x (n) is the echo signal y (n) becomes via the echo path, the power fluctuation at that time (maximum or reduced) is proportional to the echo path coupling amount c (n). すなわち、エコー信号のパワーPy(n)の逆数である損失量M(n)をマイクロホン入力信号z(n)に乗じると、マイクロホン入力信号z(n)に含まれるエコー信号y(n)に見合った量だけ損失が挿入される。 That is, when multiplied by the amount of loss is the reciprocal of a power Py (n) of the echo signal M (n) to the microphone input signal z (n), commensurate with the echo signal y included in the microphone input signal z (n) (n) loss is inserted by an amount was. これによって、エコー信号y(n)を抑圧することができる。 Thereby, it is possible to suppress the echo signal y (n).

このエコーサプレッサ302に反響路結合量推定装置100を適用したことにより、ダブルトーク状況下でも必ず帯域一括反響路結合量C(n)が算出されるため、損失器20にはエコ−抑圧のための所定の損失量が与えられる。 By applying the echo path coupling estimation apparatus 100 in this echo suppressor 302, since it surely band collectively echo path coupling amount under double talk conditions C (n) is calculated, the loss 20 Eco - for suppression predetermined loss amount is given in. 従って仮にダブルトーク状態が長く続いたとしても適正なエコー抑圧制御状態を維持することができる。 Thus even if a double-talk state continues longer able to maintain the proper echo suppression control state.

図4にこの発明の第3の実施例を示す。 Figure 4 shows a third embodiment of the present invention. この実施例はこの発明の請求項13で提案する通信路上の損失量制御装置の実施例に該当する。 This embodiment corresponds to an embodiment of the loss control device of the communication path to be proposed in claim 13 of the present invention. 通信路上の損失量制御器303は受話側及び送話側の双方に損失器10及び20が設けられ、これらの損失器10及20の損失量を適正に制御することによって、反響路の結合量が大きくなっても通信路上のループ利得を「1」以下に抑制し、ハウリングの発生を抑圧する。 By loss controller 303 of the communication path is loss 10 and 20 are provided on both the receiving side and the transmitting side, to properly control the amount of loss of these losses 10 及 20, binding of the echo path also inhibited the loop gain of the communications path to the "1" increases, suppressing the occurrence of howling.
この実施例でも帯域一括反響路結合量計算部800は、各帯域それぞれの反響路結合量C(m,f)のうちの最大値を全ての帯域を一括して代表した反響路結合量C(n)として出力する。 Band collective echo path coupling amount calculating unit 800 in this embodiment, echo path coupling amount the maximum value was represented collectively all band out of the band each echo path coupling amount C (m, f) C ( and outputs it as n).

損失量計算部810では、帯域一括反響路結合量c(n)の逆数を帯域一括の損失量L(n)として決定する。 In the loss amount calculation unit 810 determines the inverse of the bandwidth collective echo path coupling amount c (n) as a loss of bandwidth batch L (n). 決定した損失量L(n)を損失量制御部830に入力し、損失器10または損失器20によって、受話信号側または送話信号側の少なくともどちらか一方に損失を挿入する。 The determined loss L (n) is input to the loss controller 830, by the loss 10 or loss 20, it inserts a loss for at least one of the receiving signal side or transmission signal side. これにより、遠端と近端を一巡する通信路(ループ)の利得(一巡増幅量)が1を超えハウリングが発生することを抑制する。 Thus, the gain (round amplification amount) of the communication path to cycle the far end and near end (loop) suppresses the howling exceed 1 occurs.
帯域一括反響路結合量計算部800では帯域別反響路結合量C(m,f)の最大値を全帯域一括の反響路結合量とした理由は、一巡ループの周波数特性においてハウリングを起こす可能性のある最悪の場合(最大利得)にあわせて損失量を決定するためである。 Why the maximum value was defined as echo path coupling amount of all bands Bulk band collective echo path coupling amount calculating unit 800 in the band-by-band echo path coupling amount C (m, f) is likely to cause the howling in the frequency characteristic of the round loop in order to determine the amount of loss in accordance with the worst case (maximum gain) with a.

本発明の第4の実施例として、多チャネルエコー抑圧装置304の構成図を図5に示す。 As a fourth embodiment of the present invention, a block diagram of a multi-channel echo suppressor 304 shown in FIG. なお、図1と対応する部分については同一の符号を付す。 Incidentally, the same reference numerals are assigned for parts corresponding to those in FIG.
図5は受話手段410−1〜410−N(N個のスピーカ)と送話手段420−1〜420−M(M個のマイクロホン)を用いたNチャネル再生Mチャネル収音の多チャネルハンズフリー拡声通話を行う場合の、近端(自分側)においた多チャネルエコー抑圧装置304の処理を示している。 Figure 5 is receiving unit 410-1~410-N (N pieces of speaker) and the transmitter means 420-1~420-M (M number of microphones) multichannel Handsfree N-channel playback M-channel sound using when performing hands-free communication, it shows the processing of the multi-channel echo suppressor 304 placed at the proximal end (their side). 送話手段420−1〜420−Mには、遠端の相手(話者)から通信路を経由して受信された受話信号x1(n)〜xN(n)が、受話手段410−1〜410−N及び複数の反響路を介して反響したエコー信号y1−1(n)〜yN−M(n)もしくは送話信号s1(n)〜sM(n)のどちらか一方、もしくは両方(ダブルトーク状態)が入力(収音)されマイクロホン入力信号z1〜zM(n)となる。 The transmitter means 420-1~420-M, receiving speech signals received via a communication path from the far end of the party (speaker) x1 (n) ~xN (n), receiving means 410-1~ 410-n either one and multiple echo path echo signal echoed through y1-1 (n) ~yN-M (n) or transmission signal s1 (n) ~sM (n), or both (double talk state) is input (sound pickup) to the microphone input signal Z1 to Zm (n). 反響路結合量推定装置100−1〜100−Mはダブルトーク状態かどうかの如何に関わらず以下の処理により反響路結合量を推定する。 Echo path coupling estimation device 100-1 to 100-M estimates the echo path coupling amount by the following process regardless of whether a double-talk state.

反響路結合量推定装置100−1〜100−Mには、受話信号x1(n)〜xN(n)を加算した信号XSUM(n)及びマイクロホン入力信号z1(n)〜zM(n)をそれぞれ入力する。 The echo path coupling estimation device 100-1 to 100-M, the received signal x1 (n) to Xn (n) a sum signal Xsum (n) and the microphone input signal z1 (n) ~ZM a (n), respectively input.
反響路結合量推定装置100−1〜100−Mは、それぞれ、帯域別反響路結合量CX1(m,f)〜CXM(m,f)、帯域別受話信号パワーPX1(m,f)〜PXM(m,f)、帯域別入力信号パワーPZ1(m,f)〜PZM(m,f)、入力信号周波数係数Z1(m,f)〜ZM(m,f)を出力し、エコー抑圧部600−1〜600−Mに入力する。 Echo path coupling estimation device 100-1 to 100-M, respectively, per-band echo path coupling amount CX1 (m, f) ~CXM (m, f), the band-by-band received signal power PX1 (m, f) ~PXM (m, f), the band-by-band input signal power PZ1 (m, f) ~PZM (m, f), outputs the input signal frequency coefficient Z1 (m, f) ~ZM (m, f), the echo suppressing unit 600 input to -1~600-M. エコー抑圧部600−1〜600−M及び時間信号合成部700−1〜700−Mのそれぞれの内部処理は実施例1に等しい。 Each internal processing of the echo suppressor 600-1 to 600-M and time signal combining unit 700-1~700-M is equal to Example 1. 時間信号合成部700−1〜700−Mからそれぞれエコー信号を抑圧したMチャネル処理後の時間信号をそれぞれ出力する。 And it outputs the time signal after M-channel processing has been suppressed echo signals respectively from the time the signal combining unit 700-1~700-M.

以上説明した反響路結合量推定装置100、エコー抑圧装置301、エコーサプレッサ302、通信路上の損失量制御装置303はそれぞれコンピュータにコンピュータが解読可能なプログラム言語によって記述された反響路結合量推定プログラム、エコー抑圧プログラム、エコーサプレッサプログラム、通信路上の損失制御プログラム、多チャネルエコー抑圧プログラムをそれぞれインストールし、コンピュータに備えられたCPUと呼ばれる中央演算処理装置に解読させ、実行させることにより実現される。 Above-described echo path coupling estimation apparatus 100, the echo suppressor 301, the echo suppressor 302, the echo path coupling estimation program described computer to each loss amount control unit 303 of the communication path computer by enabling programming language decryption, echo suppressing program, the echo suppressor program, loss control program of the communication path, the multi-channel echo suppression program installed respectively, is decrypted in the central processing unit called a CPU provided in the computer are realized by executing. プログラムはコンピュータが読み取り可能な例えば磁気ディスク或はCD−ROMのような記録媒体に記録され、これらの記録媒体又は通信回線からコンピュータにインストールされ、コンピュータに備えられたCPUに解読されて上記した反響路結合量推定装置、エコー抑圧装置、エコーサプレッサ、通信路上の損失制御装置、多チャネルエコー抑圧装置等として機能させることができる。 Program is recorded in a recording medium such as a computer-readable such as a magnetic disk or a CD-ROM, is installed from these recording media or communication lines to the computer, and are decrypted to the CPU provided in the computer and the echo road coupling estimation apparatus, the echo suppressor, an echo suppressor, loss control device on the communication path can be made to function as a multi-channel echo suppressor or the like.

この発明による反響路結合量推定方法及び装置、エコー抑圧方法及び装置、エコーサプレス方法及びエコーサプレッサ、通信路上の損失量制御方法及び装置は多地点間電話会議システムのようにハンズフリー拡声通話を行う分野で活用される。 Echo path coupling estimation method and apparatus according to the present invention, the echo suppressing method and apparatus, the echo suppression process and the echo suppressor performs hands-free speaker-phone call as the loss control method and apparatus of the communication path multipoint teleconferencing system It is utilized in the field.

この発明の請求項3で提案する反響路結合量推定装置と請求項7で提案するエコー抑圧装置とを組合せた実施例を説明するためのブロック図。 Block diagram for explaining an embodiment in which a combination of a echo suppressor in which the echo path coupling amount estimating apparatus proposed in claim 3 is proposed in claim 7 of the present invention. 図1に示したエコー抑圧装置の内部の構成を説明するためのブロック図。 Block diagram for explaining the internal construction of the echo suppressor shown in FIG. この発明の請求項3で提案する反響路結合量推定装置と請求項10で提案するエコーサプレッサとを組合せた実施例を説明するためのブロック図。 Block diagram for explaining an embodiment in which a combination of an echo suppressor proposed in echo path coupling estimation apparatus as claimed in claim 10 proposed in claim 3 of the present invention. この発明の請求項3で提案する反響路結合量推定装置と請求項13で提案する通信路上の損失量制御装置とを組合せた実施例を説明するためのブロック図。 Block diagram for explaining an embodiment in which a combination of a loss amount control apparatus of a communication path that proposed echo path coupling estimation apparatus in claim 13 proposed in claim 3 of the present invention. この発明の多チャネルエコー抑圧装置の実施を説明するためのブロック図。 Block diagram for explaining an embodiment of a multi-channel echo suppressor of the present invention. 従来の技術を説明するためのブロック図。 Block diagram for explaining a conventional technology.

符号の説明 DESCRIPTION OF SYMBOLS

10,20 損失器 600 エコー抑圧部 100 反響路結合量推定装置 601 帯域別エコー信号110,120 周波数分析手段 パワー計算手段130,140 帯域別パワー計算手段 602 抑圧ゲイン計算手段 150 帯域別パワー比計算手段 603 ゲイン制御手段 160 帯域別パワー比最小値保持手段 301 エコー抑圧装置 700 時間信号合成部 302 エコーサプレッサ 800 帯域一括反響路結合 303 通信路上の損失量制御器 量計算部 330 損失量制御手段 810 損失量計算部 410 受話手段 420 送話手段 10,20 losses 600 echo suppressing unit 100 echo path coupling estimation device 601 band-by-band echo signals 110 and 120 the frequency analyzing unit power calculating means 130 and 140 per-band power calculating unit 602 suppression gain calculating unit 150 band-dependent power ratio calculating means 603 gain control unit 160 band-dependent power ratio minimum value holding means 301 echo loss controller quantity calculation unit 330 loss amount control means 810 loss of suppressor 700 hours the signal combining unit 302 the echo suppressor 800 band collectively echo path coupled 303 communication path calculator 410 receiving unit 420 transmitting unit

Claims (18)

  1. 受話端と送話端間の反響路結合量を推定する反響路結合量推定方法において、 In echo path coupling estimation method for estimating the echo path coupling amount between the transmitting end and the receiving end,
    受話信号を周波数領域に変換し、受話信号の周波数係数から各周波数帯域毎の受話信号パワーを計算する処理と、 Converts the received signal into the frequency domain, the process of calculating the received signal power for each frequency band from the frequency coefficients of the received signal,
    送話信号に反響路を経由した反響信号が加算された入力信号を周波数領域に変換し、入力信号の周波数係数から各周波数帯域毎の入力信号パワーを計算する処理と、 And processing echo signals via the echo path into transmission signal converts the input signal added to the frequency domain to calculate the input signal power for each frequency band from the frequency coefficients of an input signal,
    上記受話信号パワーに対する上記入力信号パワーのパワー比を各周波数帯域別に計算する処理と、 A process of calculating the power ratio of the input signal power for the received signal power for each frequency band,
    各周波数帯域毎に計算したパワー比の最小値を更新し、各周波数帯域毎のパワー比の更新した最小値を保持し、各周波数帯域毎に保持された最小パワー比を各周波数帯域別の反響路結合量として出力する処理と、 It updates the minimum value of the power ratio calculated for each frequency band, and holds the minimum value updated power ratios for each frequency band, echo the minimum power ratio held for each frequency band separately for each frequency band and outputting as a road coupling amount,
    を含むことを特徴とする反響路結合量推定方法。 Echo path coupling estimation method characterized by comprising a.
  2. 請求項1に記載された反響路結合量推定方法において、上記各周波数帯域別の反響路結合量の内の最大値を周波数帯域一括の反響路結合量として出力することを特徴とする反響路結合量推定方法。 In has been echo path coupling estimation method according to claim 1, the echo path coupled to and outputs the maximum value among the respective frequency bands by the echo path coupling amount as echo path coupling of the frequency bands simultaneously The amount estimation method.
  3. 受話端と送話端間の反響路結合量を推定する反響路結合量推定装置において、 In echo path coupling estimation device for estimating the echo path coupling amount between the transmitting end and the receiving end,
    受話信号を周波数係数に変換する第1周波数分析手段と、 A first frequency analysis means for converting a received signal into frequency coefficients,
    この第1周波数分析手段で分析した受話信号の周波数係数から各周波数帯域毎の受話信号パワーを計算する第1帯域別パワー計算手段と、 A first band-by-band power calculating means for calculating a received signal power for each frequency band from the frequency coefficients of the received signals analyzed by the first frequency analysis means,
    送話信号に反響路を経由した反響信号が加算された入力信号を周波数係数に変換する第2周波数分析手段と、 A second frequency analysis means for converting the frequency coefficients input signal echo signal is added passing through the echo path in the transmission signal,
    この第2周波数分析手段で分析した入力信号の周波数係数から各周波数帯域毎の入力信号のパワーを計算する第2帯域別パワー計算手段と、 A second band-by-band power calculating means for calculating the power of the input signal for each frequency band from the frequency coefficients of the input signal analyzed by the second frequency analysis means,
    上記受話信号パワーに対する上記入力信号パワーのパワー比を各周波数帯域別に計算する第2帯域別パワー比計算手段と、 A second band-dependent power ratio calculating means for calculating a power ratio of the input signal power for each frequency band for the received signal power,
    各周波数帯域別に計算したパワー比の最小値を更新し、各周波数帯域別のパワー比の更新した最小値を保持し、各周波数帯域別に保持された最小パワー比を各周波数帯域別の反響路結合量として各周波数帯域別に計算したパワー比の最小値を更新し、各周波数帯域別に保持された最小パワー比を各周波数帯域別の反響路結合量として出力する帯域別パワー比最小値保持手段と、 Update the minimum value of the power ratio calculated for each frequency band, and holds the minimum value updated for each frequency band by the power ratio, the minimum power ratio each frequency band different echo path coupling a retained for each frequency band update the minimum value of the calculated power ratio for each frequency band as the amount, and the band-by-band power ratio minimum value holding means for outputting a minimum power ratio held for each frequency band as a separate echo path coupling amount each frequency band,
    を備えることを特徴とする反響路結合量推定装置。 Echo path coupling estimation apparatus comprising: a.
  4. 請求項3記載の反響路結合量推定装置において、上記帯域別パワー比最小値保持手段が出力する各周波数帯域別のパワー比最小値の内からパワー比の最大値を抽出し、このパワー比最小値の内から抽出したパワー比の最大値を帯域一括反響路結合量として出力する帯域一括反響路結合量計算手段を備えることを特徴とする反響路結合量推定装置。 In echo path coupling estimation apparatus according to claim 3, extracts the maximum value of the power ratio from among the each frequency band of the power ratio minimum value output from the above-mentioned band-dependent power ratio minimum value holding means, the minimum the power ratio echo path coupling estimation device characterized by comprising a band collective echo path coupling amount calculating means for outputting as a band collectively echo path coupling amount the maximum value of the extracted power ratio among the values.
  5. コンピュータが解読可能なプログラム言語によって記述され、コンピュータを請求項3又は4の何れかに記載の反響路結合量推定装置として機能させる反響路結合量推定プログラム。 Computer is described by a readable programming language, echo path coupling estimation program to function as the echo path coupling estimation apparatus according to claim 3 or 4 computer.
  6. 受話信号を周波数領域に変換し、受話信号の周波数係数から各周波数帯域毎の受話信号パワーを計算する処理と、送話信号に反響路を経由した反響信号が加算された入力信号を周波数領域に変換し、入力信号の周波数係数から各周波数帯域毎の入力信号パワーを計算する処理と、上記受話信号パワーに対する上記入力信号パワーのパワー比を各周波数帯域別に計算する処理と、各周波数帯域毎に計算したパワー比の最小値を更新し、各周波数帯域毎のパワー比の更新した最小値を保持し、各周波数帯域毎に保持された最小パワー比を各周波数帯域別の反響路結合量として出力する処理とを含む反響路結合量推定方法で計算した帯域別反響路結合量に、受話信号を周波数分析して求めた帯域別受話信号パワーを重畳して帯域別エコー信号パワー Converts the received signal into the frequency domain, the process of calculating the received signal power for each frequency band from the frequency coefficients of the received signal, an input signal echo signal is added passing through the echo path in the transmission signal in the frequency domain converted from the frequency coefficients of the input signal and the process of calculating the input signal power for each frequency band, a process of calculating the power ratio of the input signal power for each frequency band for the received signal power, for each frequency band It updates the minimum value of the calculated power ratio, holding the minimum value updated power ratios for each frequency band, outputs the minimum power ratio held for each frequency band as a separate echo path coupling amount each frequency band processing the band-by-band echo path coupled amount calculated by the echo path coupling estimation method comprising the, band-by-band echo signal power by superimposing the band-by-band received signal power obtained a received signal by frequency analysis 計算し、送話信号に反響路を経由した反響信号が加算された入力信号を周波数分析して求めた帯域別入力信号パワーと上記帯域別エコー信号パワーの比により各周波数帯域別の抑圧ゲインを求め、入力信号周波数係数の振幅成分に上記抑圧ゲインを重畳し、周波数帯域別にエコー信号を抑圧し、エコー信号を抑圧処理した周波数係数を合成し、エコー信号を抑圧した時間信号を出力することを特徴とするエコー抑圧方法。 Calculated, the suppression gain Alternative each frequency band by the ratio of the band-by-band input signal power and the respective band echo signal power echo signal is determined by frequency analysis of the input signal added to via the echo path into transmission signal determined, by superimposing the suppression gain to the amplitude component of the input signal frequency coefficient, it suppresses the echo signal for each frequency band, to synthesize a frequency coefficient suppression processing the echo signals, to output a time signal which suppresses the echo signal echo suppressing method according to claim.
  7. 受話信号を周波数係数に変換する第1周波数分析手段と、この第1周波数分析手段で分析した受話信号の周波数係数から各周波数帯域毎の受話信号パワーを計算する第1帯域別パワー計算手段と、送話信号に反響路を経由した反響信号が加算された入力信号を周波数係数に変換する第2周波数分析手段と、この第2周波数分析手段で分析した入力信号の周波数係数から各周波数帯域毎の入力信号のパワーを計算する第2帯域別パワー計算手段と、上記受話信号パワーに対する上記入力信号パワーのパワー比を各周波数帯域別に計算する第2帯域別パワー比計算手段と、各周波数帯域別に計算したパワー比の最小値を更新し、各周波数帯域別のパワー比の更新した最小値を保持し、各周波数帯域別に保持された最小パワー比を各周波数帯域別の A first frequency analysis means for converting a received signal into frequency coefficients, a first band-by-band power calculating means for calculating a received signal power for each frequency band from the frequency coefficients of the received signals analyzed by the first frequency analysis means, a second frequency analysis means for converting an input signal echo signals via the echo path into transmission signal is added to the frequency coefficients from the frequency coefficients of the input signal analyzed by the second frequency analysis means for each frequency band a second band-by-band power calculating means for calculating the power of the input signal, and a second band-dependent power ratio calculating means for calculating a power ratio of the input signal power for each frequency band for the received signal power, calculated for each frequency band and updating the minimum value of the power ratio, and holds the minimum value updated for each frequency band by the power ratio, the minimum power ratio held for each frequency band separately for each frequency band 響路結合量として各周波数帯域別に計算したパワー比の最小値を更新し、各周波数帯域別に保持された最小パワー比を各周波数帯域別の反響路結合量として出力する帯域別パワー比最小値保持手段とによって構成される反響路結合量推定装置を備え、 It updates the minimum value of the power ratio calculated for each frequency band as a sound passage coupling amount, holding the band-by-band power ratio minimum value for outputting the minimum power ratio held for each frequency band as a separate echo path coupling amount each frequency band includes a echo path coupling estimation device constituted by means,
    この反響路結合量推定装置で計算した帯域別反響路結合量に、受話信号を周波数分析して求めた帯域別受話信号パワーを重畳し、帯域別エコー信号パワーを計算する帯域別エコー信号パワー計算手段と、 A band-by-band echo path coupled amount calculated in this echo path coupling estimation device superimposes the band-by-band received signal power obtained by frequency analysis of the received signal, band-by-band echo signal power calculation for calculating per-band echo signal power and means,
    送話信号に反響路を経由した反響信号が加算された入力信号を周波数領域に周波数分析して求めた帯域別入力信号パワーと、上記帯域別エコー信号パワー計算手段で計算した帯域別エコー信号との比によって周波数帯域別のエコー抑圧ゲインを求める抑圧ゲイン計算手段と、 A band-by-band input signal power to determine the input signal echo signal is added passing through the echo path in the transmission signal by frequency analysis in the frequency domain, the band-by-band echo signals calculated above respective band echo signal power calculating means and a suppression gain calculating means for calculating a frequency band different echo suppression gain by the ratio of,
    この抑圧ゲイン計算手段で計算した周波数帯域別のエコー抑圧ゲインと上記入力信号の周波数係数とを重畳し、各周波数帯域別にエコーを抑圧するエコー抑圧手段と、 An echo suppression means for superimposing the frequency coefficients of each frequency band of the echo suppression gain and said input signal, for suppressing an echo for each frequency band calculated by the suppression gain computing unit,
    エコー抑圧手段でエコーが抑圧された周波数係数を合成し、時間信号に合成する時間信号合成手段と、 A time signal synthesizing means for echo synthesizes the suppressed frequency coefficients, synthesizes the time signal in the echo suppressing unit,
    によって構成されるエコー抑圧装置。 Echo suppressor configured by.
  8. コンピュータが解読可能なプログラム言語によって記述され、コンピュータを請求項7記載のエコー抑圧装置として機能させるエコー抑圧プログラム。 Computer is described by a readable programming language, echo suppressing program for causing a computer to function as an echo suppressing apparatus according to claim 7 wherein.
  9. 受話信号のパワーを計算し、この受話信号パワーに請求項2記載の反響路結合量推定手段で計算した周波数帯域一括の反響路結合量を乗算し、その逆数を求めて損失量を求め、この損失量を送話信号に反響路を経由した反響信号が加算された入力信号に乗算し、入力信号に含まれるエコー信号を抑圧することを特徴とするエコーサプレス方法。 Calculate the power of the received signal, the received signal power by multiplying the echo path coupling of the frequency band simultaneously calculated by the echo path coupling estimation means according to claim 2, determine the loss seeking its reciprocal, the echo suppression wherein the reverberation signal via the echo path loss amount transmission signal is multiplied by the input signal added to suppress the echo signal contained in the input signal.
  10. 受話信号のパワーを計算する受話信号パワー計算手段と、 And the reception signal power calculating means for calculating a power of the reception signal,
    請求項4記載の反響路結合量推定装置で計算した周波数帯域一括の反響路結合量と上記受話信号パワー計算部で計算した受話信号パワーとを乗算し、その逆数を損失量として求める損失量計算手段と、 Multiplying the received signal power calculated in claim 4 echo path coupling of the frequency band simultaneously calculated by the echo path coupling estimation apparatus according to the above received signal power calculating portion, the amount of loss calculation for obtaining the reciprocal as loss and means,
    この損失量計算部で計数した損失量をマイクロホン入力信号に乗算してエコー信号を抑圧した信号として出力する損失手段と、 A loss means for outputting a signal obtained by suppressing the echo signal loss amount counted in this loss calculation unit by multiplying the microphone input signal,
    によって構成したエコーサプレッサ。 Echo suppressor configured by.
  11. コンピュータが解読可能なプログラム言語によって記述され、コンピュータを請求項10記載のエコーサプレッサとして機能させるエコーサプレッサプログラム。 Computer is described by a readable programming language, the echo suppressor program for causing a computer to function as an echo suppressor according to claim 10, wherein.
  12. 請求項2記載の反響路結合量推定方法で計算した帯域一括反響路結合量から通信ループに挿入すべき損失量を計算し、計算された損失量に従って通信路に挿入した損失器の損失量を制御することを特徴とする通信路上の損失量制御方法。 The claim 2 loss to be inserted from the calculated band collectively echo path coupling amount in the communication loop echo path coupling estimation method according to calculate the loss of the inserted loss device to the communication channel according to the calculated loss loss control method of a communication path, characterized by control.
  13. 請求項4記載の反響路結合量推定装置で計算された帯域一括音響結合量から通信ループに挿入すべき損失量を計算する損失量計算手段と、 A loss amount calculation means for calculating the amount of loss to be inserted into the communication loop from the band collectively acoustic coupling amount calculated by the echo path coupling estimation apparatus according to claim 4,
    この損失量計算手段で計算した損失量を受話側又は送話側に挿入すべきかを決定し、その決定に従って受話側及び送話側に挿入した損失器の何れかの損失量を制御する損失制御手段と、 The loss amount calculated in this loss amount calculation means determines to be inserted into the receiving side or the transmitting side, loss control for controlling one of loss of loss instrument inserted into the receiving side and the transmitting side according to the determined and means,
    を備えることを特徴とする通信路上の損失制御装置。 Loss control device on the communication path, characterized in that it comprises a.
  14. コンピュータが解読可能なプログラム言語によって記述され、コンピュータを請求項13記載の通信路上の損失制御装置として機能させる通話路上の損失制御プログラム。 Computer is described by a readable programming language, loss control program calls path causing a computer to function as the loss control device of the communications path of claim 13 wherein.
  15. Nチャネル(N>1)の受話信号を再生し、Mチャネル(M>1)の入力信号を収音する場合に発生する複数エコーを抑圧する多チャネルエコー抑圧方法であって、 Play the received signal of the N-channel (N> 1), a multi-channel echo suppressing method for suppressing multiple echoes occur when picking up an input signal of the M-channel (M> 1),
    Nチャネルの受話信号を加算した加算受話信号と、M個の入力信号それぞれを用いて請求項6記載のエコー抑圧方法でそれぞれMチャネル毎にエコーを抑圧することを特徴とする多チャネルエコー抑圧方法。 Multi-channel echo suppressing method for an addition reception signal obtained by adding the received signals of N channels, characterized in that for suppressing an echo every M channels each echo suppressing method according to claim 6, wherein using each M input signals .
  16. Nチャネル(N>1)の受話信号を再生し、Mチャネル(M>1)の入力信号を収音する場合に発生する複数エコーを抑圧する多チャネルエコー抑圧装置であって、 Play the received signal of the N-channel (N> 1), a multi-channel echo suppressor for suppressing multiple echoes occur when picking up an input signal of the M-channel (M> 1),
    Nチャネルの受話信号を加算する加算器と、この加算器で加算した加算受話信号とM個の入力信号それぞれを用いてMチャネル毎のそれぞれのエコーを抑圧する請求項7記載のエコー抑圧装置によって構成される多チャネルエコー抑圧装置。 An adder for adding the reception signal of the N-channel, by the echo suppressor according to claim 7, wherein for suppressing the respective echo every M channels with each sum the received signal and the M input signals added by the adder constructed multi-channel echo suppressor.
  17. コンピュータが解読可能なプログラム言語によって記述され、コンピュータを請求項16記載の多チャネルエコー抑圧装置として機能させる多チャネルエコー抑圧プログラム。 Computer is described by a readable programming language, multi-channel echo suppression program causing a computer to function as a multi-channel echo suppression device according to claim 16, wherein.
  18. コンピュータが読み取り可能な記録媒体で構成され、この記録媒体に少なくとも請求項5記載の反響路結合量推定プログラム、又は請求項8記載のエコー抑圧プログラム、或は請求項11記載のエコーサプレッサプログラム、請求項14記載の通信路上の損失制御プログラム、請求項17記載の多チャネルエコー抑圧プログラムの何れかを記録した記録媒体。 Computer is configured by a recording medium readable, at least according to claim 5 wherein the echo path coupling estimation program, or claim 8, wherein the echo suppressing program, or claim 11, wherein the echo suppressor program on this recording medium, wherein claim 14, wherein the communication path loss control program of a multi-channel echo recording medium recording any of the suppression program of claim 17.
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