Download presentation
1
CST Array Wizard User‘s Guide
User inputs will automatically be set up as parameters. Thus, it is unnecessary to manually define parameters. Please use only numbers as inputs.
2
Setup and Plot Farfield Array
If the Setup and Plot Farfield Array option is selected, a new farfield pattern will be created using the Farfield Array feature. All other inputs will be considered.
3
Construct Finite Array from Single Element
If the Construct Finite Array from Single Element option is selected, the “unit cell” (including ports, lumped elements, and wires) will be expanded to an array based on the Array Geometry settings. If Excitation Settings are specified, the appropriate values will be entered in the Excitation Selection dialog and the Simultaneous Excitation feature will be enabled.
4
Construct Finite Array from Single Element
Note, when creating large arrays, the macro execution can take some time. Please be patient.
5
Construct Finite Array from Single Element
With a non-rectangular lattice (Grid Angle ≠ 90), some array elements will fall outside the “S1*Number of Columns” bound as shown above. These elements will be referred to as “spill-over” elements.
6
Construct Finite Array from Single Element
The “spill-over” elements can be removed or retained, by respectively checking and un-checking the Remove spill-over elements option. In addition, the Shift first element by __ % specification allows the user to intentionally create “spill-over” elements in the first row(s) as shown in the picture on the right.
7
Simultaneous Excitation: Update Am/Ph Distribution
If the Simultaneous Excitation: Update Am/Ph Distribution option is selected, the values entered in the Excitation Selection dialog will be updated accordingly based on the Excitation Settings specified.
8
Simultaneous Excitation: Update Am/Ph Distribution
Binomial Scan Theta = 0 Cosine^2 Scan Theta = 30 Note, if Simultaneous Excitation: Update Am/Ph Distribution is used, the Array Geometry settings must be the same as when Construct Finite Array from Single Element was used. For convenience, these settings are automatically restored.
9
Perform Combine Results: Setup Am/Ph Distribution and Execute
If the Perform Combine Results: Setup Am/Ph Distribution and Execute option is selected, the Combine Results dialog will be updated appropriately, based on the Excitation Settings specified, and the farfield combination performed. As with Simultaneous Excitation: Update Am/Ph Distribution , the Array Geometry settings must match and thus are restored automatically.
10
User Defined Excitation Settings
Imported file format: Port # <tab> Mode # <tab> Amplitude/Phase Example: If the user has pre-calculated amplitude weights and/or port phase values, they can be loaded using User Defined and Load file… respectively. The imported file(s) should be formatted in the tab delimited manner shown above.
11
User Defined Excitation Settings
... ... ... ... 33 32 31 ... 18 17 16 ... 3 2 1 When using these features, the port numbering convention must be known. Ports are assumed to be numbered consecutively from Xmin to Xmax, and Ymin to Ymax. Thus, port 1 will be at (Xmin, Ymin) and will increment progressively until reaching (Xmax, Ymin). The next port number will be located at (Xmin, Ymin+1) and the cycle repeats until reaching (Xmax, Ymax).
12
Background Information
Binomial Amplitude weights: When this option is selected, the amplitude weights will be equal to the normalized binomial coefficients. The binomial coefficients can be calculated with: number of linear array elements Cosine and Cosine^2 Amplitude weights: When one of these options is selected, the amplitude weights will be calculated (and normalized) based on a cosine/cosine^2 distribution over the aperture of the array using: Cosine Cosine^2 Length of the linear array Distance from the array center
13
Background Information
Chevbyshev Amplitude weights: When this option is selected, the amplitude weights will be calculated based on Dolph-Chevbyshev synthesis. The amplitude weights can be calculated with: For odd and For even where Number of elements in a linear array relative sidelobe level (linear scale)
14
Background Information
Taylor Amplitude weights: When this option is selected, the amplitude weights will be calculated based on the modified sin pz/pz distribution, often referred to as the Taylor one-parameter distribution. The sampled amplitude weights can be calculated with: modified Bessel function of the first kind length of the linear array distance from the center of the array parameter to set the relative sidelobe level Since Bessel functions are not a standard VBA function, the equivalent summation is used: Since an infinite sum would take too long, the summation is truncated when the remaining terms are less than 1e-9.
15
Background Information
Scan Angles: The appropriate phasing at the ports to scan the main beam to the direction specified by Scan Theta and Scan Phi is automatically set up using: wavelength x location of the ith element y location of the jth element x direction offset of the ith element (non-rectangular lattice) desired theta scan angle desired phi scan angle array grid angle
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.