tailieunhanh - Bài giảng Xử lý tín hiệu số: Chương 4 - TS. Hà Hoàng Kha

Bài giảng "Xử lý tín hiệu số - Chapter 4: FIR filtering and convolution" gồm có những nội dung chính sau: Block processing methods, overlap-add block convolution method, sample processing methods, FIR filtering in direct form. Mời các bạn cùng tham khảo. | Chapter p 4 FIR filtering and Convolution Ha Hoang Kha to edit Master subtitle style Ho Chi Minh City University of Technology @ Email hhkha@ https tailieudientucntt Content Block p processingg methods Convolution direct form convolution table Convolution LTI form LTI table Matrix form Flip-and-slide form Overlap-add block convolution method Sample processing methods FIR filtering in direct form Ha H. Kha 2 FIR Filtering and Convolution https tailieudientucntt Introduction Block processing methods data are collected and processed in blocks. FIR filtering of finite finite-duration duration signals by convolution Fast convolution of long signals which are broken up in short segments DFT FFT spectrum computations Speech analysis and synthesis Image processing Sample processing methods the data are processed one at a time- with each input sample being subject to a DSP algorithm which transforms it into an output sample. Real-time applications Digitall audio d effects ff processing Digital control systems Adaptive signal processing Ha H. Kha 3 FIR Filtering and Convolution https tailieudientucntt 1. Block Processing method The collected signal samples x n n 0 1 L-1 can be thought as a block x x 0 x1 xL-1 The duration of the data record in second TL LT Consider a casual FIR filter of order M with impulse response h h0 h1 hM The length the number of filter coefficients Lh M 1 Ha H. Kha 4 FIR Filtering and Convolution https tailieudientucntt . Direct form The convolution in the direct form y n h m x n m m For DSP implementation p we must determine The range of values of the output index n The precise range of summation in m Find index n index of h m Æ 0 m M x n m Æ 0 n-m L-1 index of x n-m 0 n m L 1 Æ 0 m n m L-1 M L-1 0 n M L 1 Lx L input samples which is processed by the filter with order M yield the output signal y n of length L y L