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You can implement a uniform rectangular array (URA) with phased.URA. Array elements are distributed in the yz-plane with the array look direction along the positive x-axis. When you use phased.URA, you must specify these aspects of the array:
Sensor elements of the array
Number of rows and the spacing between them
Number of columns and the spacing between them
Geometry of the planar lattice, which can be rectangular or triangular
This example shows how to create a URA, get information about its element positions, response, and delays, and simulate its reception of two sine waves.
Create and view a six-element URA with two elements along the y-axis and three elements along the z-axis. Use a rectangular lattice, with the default spacing of 0.5 meters along both the row and column dimensions of the array. Each element is an isotropic antenna element, which is the default. Return the positions of the array elements.
hura = phased.URA([3 2]); viewArray(hura); pos = getElementPosition(hura);
The x-coordinate is zero for all elements in the array.
You can plot the array response using the plotResponse method.
% Plot the response in 3D figure; plotResponse(hura,1e9,physconst('LightSpeed'),'RespCut','3D')
Calculate the element delays for signals arriving from +/– 45 degrees azimuth and 0 degrees elevation.
hed = phased.ElementDelay('SensorArray',hura); ang = [45 -45]; tau = step(hed,ang);
The first column of tau contains the element delays for the signal incident on the array from +45 degrees azimuth and the second column contains the delays for the signal arriving from –45 degrees. The delays are equal in magnitude but opposite in sign as expected.
The following code simulates the reception of two sine waves arriving from far field sources. One of the signals is a 100-Hz sine wave arriving from 20 degrees azimuth and 10 degrees elevation. The other signal is a 300-Hz sine wave arriving from –30 degrees azimuth and 5 degrees elevation. Both signals have a one GHz carrier frequency.
t = linspace(0,1,1000); x = cos(2*pi*100*t)'; y = cos(2*pi*300*t)'; angx = [20; 10]; angy = [-30;5]; recsig = collectPlaneWave(hura,[x y],[angx angy],1e9);
Each column of recsig represents the received signal at the corresponding element of the URA, hura.