Bài giảng "Xử lý tín hiệu số - Chapter 7: Frequency analysis of signals and systems" gồm có những nội dung chính sau: Discrete time fourier transform DTFT, discrete fourier transform DFT, fast fourier transform FFT, . Mời các bạn cùng tham khảo. | Chapter p 7 Frequency Analysis of Signals and Systems Ha Hoang Kha to edit Master subtitle style Ho Chi Minh City University of Technology @ Email hhkha@ https tailieudientucntt Frequency analysis of signal involves the resolution of the signal into its freq frequency enc sinusoidal sin soidal components. components The process of obtaining the spectrum of a given signal using the basic mathematical tools is knownw as frequency q y or spectral p analysis. y The term spectrum is used when referring the frequency content of a signal. g The process of determining the spectrum of a signal in practice base on actual measurements of signal is called spectrum estimation. The instruments of software programs used to obtain spectral estimate of such signals are kwon as spectrum analyzers. Ha H. Kha 2 Frequency analysis of signals and systems https tailieudientucntt The frequency analysis of signals and systems have three major uses in DSP DSP 1 The numerical computation of frequency spectrum of a signal. 2 The efficient implementation of convolution by the fast Fourier transform FFT 3 The coding of waves such as speech or pictures for efficient transmission and storage. g Ha H. Kha 3 Frequency analysis of signals and systems https tailieudientucntt Content 1. Discrete time Fourier transform DTFT 2. Discrete Fourier transform DFT 3. Fast Fourier transform FFT Ha H. Kha 4 Transfer functions and Digital Filter Realizations https tailieudientucntt 1. Discrete-time Fourier transform DTFT The Fourier transform of the finite-energy discrete-time signal x n is defined as X ω x n e jω n n where h ω 2πf fs 2 f f The spectrum X w is in general a complex-valued function of f frequency X ω X ω e jθ ω where h θ ω arg X ω with i h -π θ ω π X ω is the magnitude spectrum θ ω is the phase spectrum Ha H. Kha 5 Frequency analysis of signals and systems .
