【正文】
an University (Natural Science Edition).,Oct,2020. 4 Sun, Xu. Kuo, Sen M. Active narrowband noise control systems using cascading adaptive filters [J]. IEEE Transactions on Audio Speech and Language Processing。load refer data SUB *output+,A 。 load coefficient to coff_buffer ||MPY *input,A LMS *coeff,*input+ 。 A(*coeff+A) 16} Where Xmem points to coefficient, and Ymem points to signal. The LMS algorithm calculates the filter output and updates each coefficient in the filter in parallel. Due to TMS320VC5402 is fixedpoint DSP, so input data, refer data and stepsize need to take format , then these data must be changed fixedpoint format, respectively multiply by 152 . Circular addressing and overflow would be noted in assemble program. Fig 5 Flow chat Using MATLAB verify algorithm, and obtaining sample values of input signal and desired signal, copying these data to assemble program, pile assemble file, parts of assemble codes given by: loop: LD 0,B STM 8,BRC 。 ADC channel and a DAC channel operate synchronously, the data transfer is in2splement format。 %calculate error hh+u*e(n)*x1。 Hzeros(1,N)。 0 is called the stepsize. 3 Convergent condition of LMS algorithm is 0181。21 ??? Where W(n) is the weight value at this time, W(n+1) is the weight value at next time,181。 yzeros(1,M)。 %output signal e(n)d(n)y(n)。 onchip peripherals contain: an enhanced 8bit hostport interface (HPI8), two multichannel buffered serial ports (McBSPs), two hardware timers and so on. Fig 4 shows the structure of hardware design system. The system consists of TMS320VC5402 and other peripherals. Fig 4 Structure of system The TLC320AC01 is analog interface circuit(AIC) .This device integrates a 14bitresolution ADC and DAC, a bandpass switchedcapacitor antialiasing input filter, a lowpass switchedcapacitor outputreconstruction filter. The internal circuit configuration and performance parameters are determined by reading control information into the eight available data registers。 BB+(*coeff+ *input +)|| { ADD Xmem ,16, A 。BB+coeff*input, AA+0A16 ST A,*coeff+0% 。store the filtered output 6 LD *refer+,A 。T=u*e MAR *+input(9) 。首先,用 MATLAB 進(jìn)行了自適應(yīng) FIR 濾波器的結(jié)構(gòu)和算法的模擬實(shí)驗(yàn), 其中 自適應(yīng)濾波 器 的輸入信號(hào) 包括 高斯噪聲。仿真結(jié)果 的 均勻性和測(cè)量結(jié)果和過(guò)濾器的效果是滿 意的 關(guān)鍵詞 自適應(yīng) FIR 濾波器, TMS320VC5402, LMS 算法。自適應(yīng)濾波器 對(duì)應(yīng)于 固定系數(shù)濾波器。當(dāng)設(shè)計(jì)自適應(yīng)濾波器 時(shí) ,信號(hào)的自相關(guān)函數(shù)和噪聲不能在事先 知道 。理想的信號(hào) d(n),從過(guò)濾信號(hào) Y(n)中減去 ,以產(chǎn)生一個(gè)錯(cuò)誤的信號(hào) e(n)。 T 指 偏 移量 , n 是過(guò)濾器 的階數(shù) 。1/ max? , 其中 max? 是相關(guān)矩陣 的 輸入向量 X(n)的最大特征值。 理想 過(guò)濾器 的 輸出是 10 ? ?nxy s * n*10?? , 181。 Hzeros(1,N)。 e(n)d(n)y(n)。工作速度可達(dá)到 100MIPS。 圖 4 結(jié)構(gòu)系統(tǒng) 該 TLC320AC01 是模擬接口電路( AIC)。 EPROM 的大小為32K8bit; TMS320VC5402 的 32 KB 的引導(dǎo)地址范圍 為 8000h0ffffh 。自適應(yīng) FIR 濾波器的軟件設(shè)計(jì)使用匯編語(yǔ)言完成。使用同步串行端口初始化 AC01,并巧妙地適用于指揮閑置 1 。 BB+(*coeff+ *input +)|| { ADD Xmem ,16, A 。Au*e*x LMS *coeff,*input+ 。store final coefficient STH B,*output 。 pute u*e(n) STH A,deltau LD deltau,T 。因此,過(guò)濾效果 越 好。 2 郭森 茂 ,閆生 .數(shù)字信號(hào)處理器模式 [M].清華大學(xué)出版社, 2020 年。