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TAYLORWIN

Purpose:

Multiplies a series with a Taylor Window.

Syntax:

TAYLORWIN(series, ampflag, nbar, attn)

Alternate Syntax:

TAYLORWIN(N, ampflag, nbar, attn)

Returns:

A series.

Example:

W1: gsin(1000, 0.001, 45)

W2: taylorwin(w1)

W1 contains a 1000 point sinewave with a frequency of 45 Hz. W2 multiplies the sinewave with a Taylor window.

Example:

W1: gsin(1000, 0.001, 45)

W2: taylorwin(w1, 5, -35)

Same as the first example except the number of approximately constant sidelobes is 5 and the sidelobe attenuation is -35 dB.

Example:

W1: taylorwin(100, 5, -35)

Creates a 100 point Taylor window where the number of approximately constant level sidelobes is 5 and the sidelobe attenuation is -35 dB.

Remarks:

Taylor windows are similar to Dolph-Chebyshev windows. The Taylor window approximates the minimization of the main lobe width in the Dolph-Chebyshev window, but allows the sidelobe levels to decrease beyond a certain frequency.

Because the Taylor distribution avoids edge discontinuities, the window sidelobes decrease monotonically.

The Taylor window coefficients are not normalized.

Taylor windows are typically used in radar applications, such as weighting synthetic aperture radar images, circular array antennas and antenna design.

nbar is the number of approximately equal sidelobes adjacent to the mainlobe and should satisfy:

nbar ≥ 2 A² + 0.5

where:

A = acosh(10 ^attn/20 ) / π

otherwise the sidelobe level specified is not guaranteed.

The attn parameter specifies the maximum sidelobe level in dB relative to the mainlobe level.

If the input is an integer with a value of N, an N point Taylor window is returned.

See GTAYLORWIN to also create an N point Taylor window.

See CHEBWIN to multiply a series with a Dolph-Chebyshev window.

See Also:

CHEBWIN

FFT

GHAMMING

GKAISER

GTAYLORWIN

PSD

SPECTRUM

WINFUNC