Using Excel to Plot Stream Data Captured with ZTI Spectrum Display software

Transcription

1 Using Excel to Plot Stream Data Captured with ZTI Spectrum Display software Z Technology Application Note No: 22 Introduction: Z Technology Spectrum Display software used with the R-507 meter has the capability to record RF measurements at high speed. This high speed measurement mode is called Streaming. This is Spectrum Display Option STR. It gets its name from the method the data is gathered. The Spectrum Display software sends a command to the meter via it s RS-232 port to set a single frequency, and IF bandwidth (NB for 15 khz, WB for 150 khz), then a command to stream measurement data to the connected PC at the fastest rate possible. In this mode measurement data is sent to the PC at a rate of about 4.5 milliseconds per measurement or a about 230 measurements per second. The Spectrum Display software displays the measured data in the Stream tab as a graph of RF field strength vs time. The graph is updated each second, or user programmed time. Spectrum Display also calculates Maximum, Average, Minimum, and Standard Deviation statistics about the data. The user may elect to record the just the statistics data or both the statistics data and the streamed data to a comma delimited Text file. Each second or user defined time period the chosen data will be recorded to a file as a single line in the file, a record. The maximum streaming time for one record is 10 seconds. This application note will describe: Setting up Spectrum Display to record data Choosing which stream data to record Open a Data File Start Recording Stream Data Field Definition Example Stream data Import of Stream data into Excel Graph of Stream data with Excel. To use Excel to plot spectrum data from the Spectrum Display application, use this same procedure, except record data with the Spectrum tab, instead of the Stream tab within the Spectrum Display application. Then import the Sweep Points into excel instead of importing the Stream Points.

2 Setting up Spectrum Display to record data Before recording data first you need to choose what data will be recorded. There are several options. Choosing which stream data to record If the Spectrum Tab is active when recording then Spectrum Data is recorded. The data recorded may be the Standard data and the Statistics, or the Standard data, Statistics, and Spectrum Points. (See Field Definitions later in this document.) The Standard data are the first 8 fields, Statistics is the next 4 fields, Spectrum Points are the next 500 (or 1000) measurements that make up the spectrum. If the Stream Tab is active when recording then Stream Data is recorded. The recorded data may be just the Statistics data, or the Statistics data and the Stream Points.. (See Field Definitions later in this document.) The Statistics are the first 12 fields, The Stream points are the following ~230 measurements per second. If the Stream tab is set up to stream for one second ~230 measurements would be included in that measurement record. If the Stream tab is set up to stream for 10 seconds, then about ~2300 measurements would be in that measurement record. 1. Start the Spectrum Display software application. 2. From the Spectrum Display Tools menu select Options. The Spectrum Display Options screen appears. Select the Data Records tab. Notice that none of the boxes are checked. We must check the appropriate boxes to record the data we want. Note also that the data record fields are accumulative. You may not select the last fields without selecting the preceding fields. 3. In the Data Records section, check the Spectrum Data box then check it s Standard data and Spectrum Points box. Check the Stream Data box and it s Stream Points Box. 2

3 Open a Data File 1. From the File Menu select New Data File. The Spectrum Display application defaults to put the new file in C:\My Documents\Spectrum Display folder. The Open screen appears. Type a file name (example: test ). Then click Open 3

4 Start Recording 1. From the File Menu select Record Data. The status line at the bottom of the Spectrum Display screen will display RECORDING 2. To Stop Recording, from the File Menu select Stop Recording 3. To close the data file, from the File Menu select Close data file. 4

5 Stream Data Field Definition Stream Record - Statistics Date Time Frequency MHz Blank Power Units Latitude Longitude Blank Blank Blank Blank Stream Record (cont) Statistics $st:version Stream Type Threshold Time On Time Off Measurement Time Max Average Min Standard Deviation Range Stream Record (cont) - Stream Data Points Number of Pre-trigger Points Total Number of Points Stream Data Points Latitude (WGS_1984 Decimal Degrees) Longitude (WGS_1984 Decimal Degrees) Stream Type: 0=Non-pulsed signal (threshold field left blank) 1=Pulsed Signal Threshold = Threshold in power units for the pulsed signal (left blank for stream type=0) Sweep Data Records Sweep Record - Standard Data Date Time Frequency MHz Integrated Power Power Units Latitude Longitude Standard Deviation Hi-Low Difference Tilt Peak Sweep Record (cont.) - Spectrum Statictics $sw:version Sweep Type Sweep Width Outer Marker Width Inner Marker Width Noise Floor Max Average Min Sweep Record (cont) - Spectrum Data Number of Spectrum Spectrum Data Points Points Latitude (WGS_1984 Decimal Degrees) Longitude (WGS_1984 Decimal Degrees) Sweep Type: 0 = 15 khz IF, 5 MHz wide 500 points 1 = 15 KHz IF, 10 MHz wide 1000 points 2 = 150 khz IF, 10 MHz wide 500 points 3= 150 khz IF, 20 MHz wide 500 points 5

6 Example Stream data Below is an example of one record of streaming data. It follows the format described above in the Stream Data Field Definition In the data file it is all one line or record. For the purposes of displaying it here the line wraps to subsequent lines. Notice the definition for field #25 is Total Number of Points In the example below field #25 is 232. That means that the following two hundred thirty two points are the streamed measurements. These are the points that we will want to graph in excel for this record. 6/16/2004,11:33:12 PM, ,MHz,,dBm, , ,,,,,$st:1.0,1,-90.0,0.000,1.021, ,-49.9,- 50.7,-51.5,0.3,1.6,0,232,-50.4,-50.8,-51.0,-50.4,-50.4,-50.2,- 50.6,-50.4,-50.7,-50.3,-50.7,-50.9,-50.5,-50.8,-50.4,-50.9,- 50.6,-50.9,-50.3,-50.5,-50.4,-50.5,-50.8,-50.3,-50.7,-50.4,- 50.9,-50.0,-50.2,-50.3,-50.5,-50.3,-49.9,-50.8,-50.7,-51.0,- 50.9,-50.4,-50.3,-50.8,-50.2,-50.3,-50.8,-50.2,-50.7,-50.4,- 50.5,-50.3,-51.0,-50.4,-50.1,-50.8,-50.3,-50.2,-50.3,-49.9,- 50.3,-51.0,-50.2,-50.3,-50.8,-50.2,-50.1,-50.8,-50.0,-50.5,- 50.7,-50.7,-50.3,-50.3,-50.4,-50.3,-51.1,-50.2,-50.5,-50.5,- 50.5,-50.3,-50.7,-50.5,-50.4,-51.1,-50.3,-50.9,-50.5,-50.5,- 50.0,-50.5,-50.6,-50.8,-50.9,-50.2,-50.9,-50.8,-50.9,-50.5,- 50.7,-51.0,-50.8,-50.7,-51.1,-50.7,-50.2,-50.5,-50.5,-50.4,- 49.9,-50.7,-50.7,-50.9,-50.3,-50.3,-50.5,-50.5,-50.4,-51.0,- 50.8,-51.0,-51.2,-50.7,-50.5,-50.7,-50.3,-50.3,-50.9,-50.3,- 51.0,-50.9,-50.8,-50.8,-50.7,-50.3,-50.5,-50.3,-50.5,-50.7,- 50.7,-50.7,-50.2,-50.4,-50.2,-50.3,-50.7,-50.2,-50.8,-50.7,- 50.8,-50.8,-50.9,-50.7,-50.9,-50.7,-50.8,-50.7,-51.5,-50.4,- 50.5,-50.8,-50.5,-50.7,-51.2,-51.0,-51.0,-51.1,-51.1,-50.9,- 50.6,-50.6,-50.7,-50.9,-50.8,-51.3,-51.2,-51.0,-51.3,-51.1,- 51.3,-50.9,-50.9,-50.8,-50.7,-50.9,-50.7,-50.4,-50.4,-50.7,- 50.9,-50.9,-50.7,-50.7,-50.8,-51.0,-50.4,-50.7,-50.7,-50.7,- 51.0,-50.7,-50.7,-50.5,-50.5,-50.7,-50.7,-50.7,-50.6,-50.4,- 50.4,-50.2,-50.9,-50.8,-50.3,-50.5,-50.9,-50.8,-50.7,-51.1,- 50.9,-51.0,-51.5,-50.8,-50.9,-51.2,-50.7,-51.1,-50.9,-51.4,- 51.2,-51.5,-51.2,-50.8,-51.1,

7 Import of Stream data into Excel Given the records to be imported into Excel are in a file C:\My Documents\Spectrum Display\Test.txt 1. Open Excel 2. Click the File menu the click Open, an Open screen appears. 3. Browse to C:\My Documents\Spectrum Display\ 4. Under the Files of Type pull down box, select Text Files (*.prn, *.txt, *.scv) 5. In the Open window you now see the Test.txt text file. Double click on it to open it. 7

8 6. A Text Import Wizard Step 1 or 3 screen appears. Click the Delimited button then Click Next 7. Text Import Wizard Step 2 of 3 screen appears. In the Delimiters section Un- Check the Tab Box, Check the Comma box, then Click Next. 8

9 8. Text Import Wizard Step 3 of 3 screen appears. Click Finish 9. An Excel screen appears with the data from Spectrum Display Test.txt file imported, with the comma separated values each in a column. 9

10 Graph of Stream data with Excel 1. Remember that the 25 th field was the total number of stream points for the first data record. If we scroll over to column Y we see the number 232, the total number of stream points in the first record. Column Z begins the first stream point. Note also that subsequent records have about the same number of stream points per record. 2. Use the horizontal scroll bar to scroll to the right to see where the 232 nd data point is. It is in Column IU. Therefore in order to graph the stream data for this record, we want to highlight all the cells from Z1 to IU1 10

11 Highlighted cells: 3. Once the Cells are highlighted then click on the Chart Wizard button on the tool bar. The Chart Wizard - Step 1 of 4 Chart Type screen appears. Click on the Line type chart icon, then click Next 11

12 4. The Chart Wizard Step 2 of 4 Chart Source Data screen appears. Click Next 5. The Chart Wizard Step 3 of 4 - Chart Options screen appears. If you d like to label the chart or label the chart axis fill in the appropriate fields with your chosen labels, then click Next. 12

13 6. The Chart Wizard Step 4 of 4 Chart Location screen appears. Click As new sheet then click Finish 7. The graphed Stream data points appear as a chart on a new sheet in Excel. Save the file to a name of your liking for later analysis. 13