In order to scan the distribution of electric field on a DUT, three parameters are needed to be known:
<ul><li><p> Dimensions of the probed (scanned) area in X and Y directions (D_PXD<sub>PX</sub>, D_PYD<sub>PY</sub>);</p></li><li><p>
The step size âX and âY that represents the spacing between points along X-axis and Y-axis, respectively;
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Probe height or the distance of the probe to the DUT surface.
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To be more precise, one needs N_(N<sub>x )ï´ N_y </sub> x N<sub>y</sub> points to scan the whole area, where N_x=D_XPD<sub>XP</sub>/âX and N_Y=D_YPD<sub>YP</sub>/âY. For instance, 4624 points (68 ï´ x 68) are needed in order to scan a 34 mm ï´ x 34 mm Patch Antenna with resolution of 0.5 mm (500 μm). The effects of the Step Size (scan resolution) and Probe Height on the 2D Amplitude near field maps for 2.349 GHz Patch Antenna are shown in Figure 4.8. <center>[[Image:neoscanfig_4_8.png|thumb|center|600px|<i><b>Figure 4.8</b>: The effects of the Step Size (scan resolution) and Probe Height on the 2D Amplitude near field maps for 2.349 GHz Patch Antenna.</i>]]</center>
To set scan parameters, press âScan Settingsâ tab in [[NeoScan]] Mapping Utility program (Figure 4.9).
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<center>[[Image:neoscanfig_4_9.png|thumb|center|600px|<i><b>Figure 4.9</b>: NeoScan Mapping Utility program: Scan Settings Tab.</i>]]</center>
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Switch ON mode enable the user to scan the three channels simultaneously using a single Lock-in Amplifier.
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Select the channel(s) you want to scan by checking the check boxes (Figure 4.10).
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<center>[[Image:neoscanfig_4_10.png|thumb|center|600px|<i><b>Figure 4.10</b>: Setting Scan Parameters in Scan Settings Tab.</i>]]</center>
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Use the Data Label text boxes to choose a name of the files the data to be written. By default the program automatically reads the current working channel. âInformationâ editor enables a user to add a text on the data file header.
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The Data Label should have a maximum of 25 characters. Do not use âEmpty Spaceâ or any of the following characters: ` ! @ " # $ % ^ & * ( ) + = \ | / { } [ ] , > < : ; ?. Note that it is allowed to use âdotâ in project name.
</p></li></ul>Â </li><li><p> Enter the number of points you want to scan in X and Y direction in entry boxes labeled âNo. Point Xâ and âNo. Point Y,â respectively (Figure 4.10).</p></li><li><p>
Set the step size in each direction in entry boxes labeled âStep Size Xâ and âStep Size Y,â respectively. These values are in mm.
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Select âWhat Axis to Scan First?â By default the program start scanning Y-axis first. In either case the scan data is written in a file in the same format, see Figure 4.11.
 <center>[[Image:neoscanfig_4_11.png|thumb|center|600px|<i><b>Figure 4.11</b>: Setting directions of scan using âWhat Axis to Scan First?â.</i>]]</center></p> <ul><li><p> The information panel will display the total number of points that has to be scanned (N_x ï´ N_xN<sub>x</sub> x N<sub>y</sub>) in the box labeled âTotal No. of Pointsâ.</p></li><li><p>
The program will also calculate the âSingle Move Timeâ for each scan point (without delay) and displays the âEstimated Scan Timeâ.
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The user can control the dwell time from âDwell Controlâ key (Figure 4.12). The Dwell Time is the amount of time spent recording the signal for one data point for a channel before moving to the next point. By default, âDwell Controlâ key is set to âAutoâ. This introduces few msec dwell time during the scan. To change the dwell time, select the âManualâ option from âDwell Controlâ button and enter the desired value in box labeled âManual Move Timeâ in âManual Move Settingâ section (Figure 4.12). You can view the new âEstimated Scan Timeâ by pressing the âUpdate Scan Timeâ button.
â</p>â</li></ul>Â <center>[[Image:neoscanfig_4_12.png|thumb|center|600px|<i><b>Figure 4.12</b>: Manual Move Settings in Scan Settings Tab.</i>]]</center>
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==== Scan Control Page====
It is assumed that the scan parameters are set and the scan measurement setup has been setup. In order to start the scan, press âScan Controlâ tab in [[NeoScan]] Mapping Utility program (Figure 4.13).