MATLAB: Where to find the phased.URA steering vector equation

Question

after defined URA using phased.URA, using phased.SteeringVector, I can get the URA steering vector. 1. where I can find the math equation behind phased.SteeringVector function? 2. if I have a 5×5 URA, the phased.SteeringVector gives a 25-element vector of the URA, how do I link the elements in the vector to the elements in the URA, or how do I build a 5×5 matrix, its elements match 5×5 URA elements?

Answer 1

You can find the general equation here at

http://www.antenna-theory.com/arrays/arrayfactor.php

There is a one to one mapping between the elements and weights. For URA, I think the index follows the MATLAB convention of matrix indexing. You can confirm this by using viewArray and turn on ShowIndex parameter.

HTH