Construct Dolph-Chebyshev window object
sigwin.chebwin creates a handle to a Dolph–Chebyshev window object for use in spectral analysis and FIR filtering by the window method. Object methods enable workspace import and ASCII file export of the window values.
The Dolph-Chebyshev window is constructed in the frequency domain by taking samples of the window's Fourier transform:
determines the level of the sidelobe attenuation. The level of the sidelobe attenuation is equal to . For example, 100 dB of attenuation results from setting
The discrete-time Dolph-Chebyshev window is obtained by taking the inverse DFT of and scaling the result to have a peak value of 1.
H = sigwin.chebwin returns a Dolph-Chebyshev window object H of length 64 with relative sidelobe attenuation of 100 dB.
H = sigwin.chebwin(Length) returns a Dolph–Chebyshev window object H of length Length with relative sidelobe attenuation of 100 dB. Length requires a positive integer. Entering a positive noninteger value for Length rounds the length to the nearest integer. A window length of 1 results in a window with a single value equal to 1.
H = sigwin.chebwin(Length,SidelobeAtten) returns a Dolph-Chebyshev window object with relative sidelobe attenuation of atten_param dB.
Dolph-Chebyshev window length.
The attenuation parameter in dB. The attenuation parameter is a positive real number that determines the relative sidelobe attenuation of the window.
|generate||Generates Dolph-Chebyshev window|
|info||Display information about Dolph–Chebyshev window object|
|winwrite||Save Dolph-Chebyshev window object values in ASCII file|
Handle. To learn how copy semantics affect your use of the class, see Copying Objects in the MATLAB® Programming Fundamentals documentation.
Default length N=64 Dolph–Chebyshev window with 100 dB relative sidelobe attenuation:
Generate length N=128 Chebyshev window with 120 dB attenuation, return values, and write ASCII file:
H=sigwin.chebwin(128,120); % Return window with generate win=generate(H); % Write ASCII file in current directory % with window values winwrite(H,'chebwin_128_100')
Harris.F.J. "On the Use of Windows for Harmonic Analysis with the Discrete Fourier Transform." Proceedings of the IEEE®. Vol. 66, 1978, pp. 51–83.