摘要:
A plurality of acoustic transfer functions for a plurality of sets of different positions of a loudspeaker and a microphone in an acoustic system are measured by an acoustic transfer function measuring part. The plurality of measured acoustic transfer functions are used to estimate poles of the acoustic system by a pole estimation part, and a fixed AR filter is provided with the estimated poles as fixed values. A variable MA filter is connected in series to the fixed AR filter and the acoustic transfer function of the acoustic system is simulated by the two filters. The filter coefficients of the variable MA filter are modified with a change in the acoustic transfer function of the acoustic system.
摘要:
In an adaptive estimation of an acoustic transfer function of an unknown system, a forward linear prediction coefficient vector a(k) of an input signal x(k), the sum of forward a posteriori prediction-error squares F(k), a backward linear prediction coefficient vector b(k) of the input signal x(k) and the sum of backward a posteriori prediction-error squares B(k) are computed. Letting a step size and a pre-filter deriving coefficient vector be represented by .mu. and f(k), respectively, a pre-filter coefficient vector g(k) is calculated by a recursion formula for the pre-filter coefficient vector g(h), which is composed of the following first and second equations: ##EQU1##
摘要:
In an echo cancelling method of a p-order fast projection algorithm which subtracts an estimated echo signal y(k) from a microphone output signal u(k) to obtain an error signal e(k), adaptively calculates a pre-filter coefficient .beta.(k) from the auto-correlation of a received speech signal x(k) and the error signal, generating an intermediate variable z(k) updated by a coefficient s(k) obtained by smoothing the pre-filter coefficient, convolutes the received speech signal x(k) and the intermediate variable z(k), calculates the inner product of the auto-correlation of the received speech signal and the smoothed pre-filter coefficient s(k) and adding the inner product and the convoluted output to obtain the estimated echo signal, the magnitudes of the received speech signal x(k) and the error signal e(k) are compared and when the result of comparison satisfies a predetermined condition, a reset signal is generated to set the pre-filter coefficient .beta.(k) to zero for at least a period of time p, thereby preventing the accuracy of estimated echo characteristics from lowering during double-talk or send single-talk.
摘要翻译:在从麦克风输出信号u(k)中减去估计回波信号+ E,cir y + EE(k)以获得误差信号e(k)的p阶快速投影算法的回波消除方法中,自适应地计算 来自接收到的语音信号x(k)的自相关的预滤波器系数β(k)和误差信号,生成由通过平滑预处理得到的系数s(k)更新的中间变量z(k) 滤波器系数,对接收到的语音信号x(k)和中间变量z(k)进行卷积,计算接收的语音信号的自相关和平滑的预滤波器系数s(k)的内积, 产品和卷积输出以获得估计的回波信号,接收到的语音信号x(k)和误差信号e(k)的大小进行比较,并且当比较结果满足预定条件时,产生复位信号 将预滤波器系数β(k)设置为零 一段时间p,从而防止估计的回波特性的精度在双向通话或发送单通话期间降低。
摘要:
Even if received signals are highly cross-correlated, echoes can be effectively cancelled and no psychoacoustical problems arise. A received signal xi(k) (where i=1, 2, . . . , N) and an additive signal ai(k) are added together, and the added output is used to drive a speaker i and input into an echo cancellation filter 405i. The received signal xi(k) and the additive signal ai(k) are input into adaptive filters 401i and 402i, respectively. The difference between the sum of the outputs from all the filters 401i and all the filters 402i and an echo ym(k) is detected as an error em(k). The coefficients of all the filters 401i and 402i are updated to reduce the error em(k). When the error em(k) is made sufficiently small, the coefficients of the filters 402i are transferred to the filters 405i. The sum of the outputs from all the filters 405i is detected as an echo replica, and the difference between the echo replica and the echo ym(k) is output.
摘要:
A received signal vector x(n), a coefficient error covariance matrix P(n) from a memory part 12 and a forgetting factor .nu. from a memory part 13 are provided to a gain calculating part 14 to obtain a gain vector k(n). The thus obtained gain vector k(n) and an error e(n) between an echo and an echo replica are multiplied in a multiplying part 16. The multiplied output and a filter coefficient h(n) from a memory part 18 are added together to update the latter. The thus updated filter coefficient is used as the filter coefficient of an estimated echo path (an FIR filter, for example). The coefficient error covariance matrix P(n), the gain vector k(n), the received signal vector x(n) and the forgetting factor .nu. are provided to an updating part 19 to update the coefficient error covariance matrix P(n), and an adjustment matrix A representing an expectation of an impulse response variation of an echo path is added to the updated coefficient error covariance matrix P(n) and the added value is used as a new coefficient error covariance matrix P(n).
摘要:
Wiring circuit boards with bumps can be manufactured such that stable bump connections are possible and plating pre-treatments or other difficult operations are rendered unnecessary. By utilizing a technique whereby a bump-formation etching mask 7 is formed on a bump-forming surface 3a of a metal foil 3 which has a thickness that is the sum of the thickness t1 of the wiring circuit 1 and the height t2 of the bumps 2 which are to be formed on the wiring circuit 1 (t1+t2), and then the bumps 2 are formed by half-etching the metal foil 3 to a depth corresponding to the desired bump height t2 from the bump-formation etching mask 7 side, wiring circuit boards with bumps can be manufactured such that stable bump connections are possible and plating pre-treatments or other complex processes are rendered unnecessary.
摘要:
A semiconductor element mounting interposer is produced by (A) forming a conducting circuit that comprises motherboard connecting electrodes 2 and plated leads 3 on an insulating base film 1; (B) forming a patterning resin layer 5 over the conducting circuit 4; (C) etching patterning resin layer 5 so as to expose the motherboard connecting electrodes 2 and plated leads 3; (D) masking plated leads 3 with an electroplating resist layer 6; (E) depositing an electroplated metal layer 7 over the exposed motherboard connecting electrodes 2; (F) removing the electroplating resist layer 6; (G) removing the exposed plated leads 3 through etching; and (H) where the patterning resin layer 5 is a polyimide precursor layer, bringing about complete imidation of the polyimide precursor layer.
摘要:
The present invention relates to a block copolymer (A) including a (meth)acrylic polymer block (a) and an acrylic polymer block (b). The (meth)acrylic polymer block (a) is preferably copolymerized with a monomer having a functional group having high cohesive force, such as a carboxyl group, so that the 5%-weight-loss temperature is 300° C. or more or the tensile strength is 3 MPa or more, and the hardness measured by a type A durometer according to JIS K6253 is 50 or less, and a compression set measured after 22 hours at 70° C. is 45% or less. The block copolymer (A) exhibits excellent thermal decomposition resistance and low compression set at high temperatures. The block copolymer (A) can be used as a soft material for automobile, and has low hardness, high adhesion, high oil resistance, high weather resistance, high heat resistance, high recycling property, high tensile properties, and high wax remover resistance.
摘要:
The present invention provides a novel acrylic block copolymer rich in flexibility and excellent in mechanical strength, moldability, oil resistance, heat resistance, thermal decomposition resistance, weather resistance, and compression set, and further rich in reactivity. The present invention also provides compositions, seal products, and automobile, electric, and electronic parts, all of which include the acrylic block copolymer. The acrylic block copolymer includes a methacrylic polymer block (a) and an acrylic polymer block (b), at least one of the polymer blocks containing, in its main chain, at least one acid anhydride group (c) represented by formula (1): (wherein R1s each represent hydrogen or a methyl group and may be the same or different, n represents an integer of 0 to 3, and m represents an integer of 0 or 1).
摘要:
The present invention relates to a block copolymer (A) including a (meth)acrylic polymer block (a) and an acrylic polymer block (b). The (meth)acrylic polymer block (a) is preferably copolymerized with a monomer having a functional group having high cohesive force, such as a carboxyl group, so that the 5%-weight-loss temperature is 300° C. or more or the tensile strength is 3 MPa or more, and the hardness measured by a type A durometer according to JIS K6253 is 50 or less, and a compression set measured after 22 hours at 70° C. is 45% or less. The block copolymer (A) exhibits excellent thermal decomposition resistance and low compression set at high temperatures. The block copolymer (A) can be used as a soft material for automobile, and has low hardness, high adhesion, high oil resistance, high weather resistance, high heat resistance, high recycling property, high tensile properties, and high wax remover resistance.