Matlab Program For Dolph Chebyshev Array Worksheets
Antenna-Theory.com - Dolph-Chebyshef Weighting Example for Antenna Arrays Dolph-Chebyshev Example Previous: (Home) Page In the previous page on, the Dolph-Tschebysheff method was introduced. On this page, we'll run through an example. Consider a N=6 element array, with a sidelobe level to be 30 dB down from the main beam ( S=31.6223). We'll assume the array has half-wavelength spacing, and recall that the Dolph-Chebyshev method requires uniform spacing and the array to be steered towards broadside (and yes, everyone spells Chebyshef in a different way, which is why I keep changing the spelling).
Fostex Full Range Loudspeakers. The array has an even number of elements, so we'll write the array factor as: Using the, the above equation can be rewritten as: We'll calculate our parameter ( ) as: Then we'll substitute for cos(u) into the last equation for the AF as described previously: We now have a polynomial of order N-1 = 5, so we'll use the Chebyshef polynomial T5(t), and equate that to our new array factor: The above equation is valid for all values of t. Hence, the terms that multiply t must equal, the terms that multiply t cubed must be equal, and the terms that multiply t to the 5th power must be equal.
As a result, we have 3 equations and 3 unknowns, and we can easily solve for the weights: The resulting normalized AF is plotted in Figure 1. Normalized array factor for the example on this page. Note that as desired, the sidelobes are equal in magnitude and 30 dB down from the peak of the main beam. The beamwidth obtained here (approximately 60 degrees) is the minimum possible beamwidth obtainable for the specified sidelobe level using any weighting scheme. This is the Dolph-Tschebysheff method.
The basic math is all used in designing digital filters that have equal-ripple filter characteristics in the pass and stop bands. Note that if you understand digital signal processing, weight selection in antenna arrays is simple. And if you've learned something about weighting methods in antenna arrays, you've learned something about designing filters for digital systems.
The underlying mathematics is largely the same. Next: (Main) (Home) (Home).
Error in dolphchebyshev array. 180)*pi)% Finding the Dolph-Chebyshev weight matrix for the array w. Has the function definition and the code for.
Copyright (c) 2011, Amol Mahurkar All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution * Neither the name of the Pune University nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. Pokemon Black For Psp. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 'AS IS' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.