LitePoint IQdebugUser’s GuideCopyright © 2008, LitePoint CorporationAll rights reservedRESTRICTED RIGHTS LEGENDNo part of this document may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language or computer language, in any form or by any means, electronic, mechanical, magnetic, optical, chemical, manual, or otherwise, without the prior written permission of LitePoint Corporation.DISCLAIMERLitePoint Corporation makes no representations or warranties with respect to the contents of this manual or of the associated LitePoint Corporation products, and specifically disclaims any implied warranties of merchantability or fitness for any particular purpose. LitePoint Corporation shall under no circumstances be liable for incidental or consequential damages or related expenses resulting from the use of this product, even if it has been notified of the possibility of such damages.If you find errors or problems with this documentation, please notify LitePoint Corporation at the address listed below. LitePoint Corporation does not guarantee that this document is error-free. LitePoint Corporation reserves the right to make changes in specifications and other information contained in this document without prior notice.TRADEMARKSLitePoint and the LitePoint logo, IQview IQflex, IQnxn, and IQmax are registered trademarks and IQsignal, IQwave, IQfact, IQcheck, IQdebug, IQmeasure, IQtest, IQexpress, IQturbo, IQultra, TrueChannel, and TrueCable are trademarks of LitePoint Corporation. Microsoft Windows is a registered trademark of Microsoft Corporation in the United States and/or other countries. All trademarks or registered trademarks are owned by their respective owners.CONTACT INFORMATIONLitePoint Corporation575 Maude CourtSunnyvale, CA 94085-2803United States of AmericaTelephone: +1.408.456.5000Facsimile: +1.408.456.0106LITEPOINT TECHNICAL SUPPORT/supportTelephone: +1.408.456.5000Available: weekdays 8am to 6pm, Pacific Standard Time.E-mail: support@Part Number: 1075-5102-004July 2008Table of ContentsPreface (3)Who Should Use This Guide (3)Getting Product Updates (3)Conventions Used in This Manual (3)IQdebug Application (5)Launching IQdebug (6)IQdebug Menu Bar (7)File Menu (7)Edit Menu (8)Wave Menu (8)Analyze Menu (8)Update Menu (9)Help Menu (9)Connecting to a Test System (9)Selecting the Operating Mode (11)Monitor Mode (11)Control Mode (12)Controlling the Test Instrument (13)Changing VSA Settings in Control Mode (13)VSG Settings in Control Mode (16)Using VSG Wave Files in Control Mode (17)Screen Background Color (17)Performing Data Captures in Control Mode (18)Automatic Gain Control in Control Mode (20)Power Versus Time Display (21)Zoom (21)Analysis (21)PrefaceThe LitePoint IQdebug ™ User’s Guide describes how to use the LitePoint IQdebug application to monitor the status of the test instrument.The preface includes the following topics:∙ Who should use this guide ∙ Getting product updates ∙Conventions used in this manualWho Should Use This GuideThe LitePoint IQdebug User’s Guide is intended for test engineers, IT administrators and sales engineers who use the LitePoint test instruments to monitor the status of the instruments.Getting Product UpdatesLitePoint makes product updates available on its website at . In order to download these updates, you must be a valid, registered user of the Client Center and have a current software maintenance agreement with LitePoint for the product or products you wish to download.Conventions Used in This ManualThis document uses the typographic conventions listed in the table below.BoldIndicates text the user must enter or select, such as, menu items, buttons andcommands.Example: In the VSA window system menu, choose Setup > Parameters .Italics Indicates emphasisExample: For detailed information about expanding the frames, refer to the topic Expanded Viewing .Monospace Represents filename, code, function name, variable name, argument name,program examples etc.Example: The lp_gps_api.h contains the error structure as shown below.Indicates that it is a tip. Provides users with useful tips.Example: If there are multiple signal streams present in the captured/loadedwaveform, a separate spectrogram plot can be displayed for each stream.Indicates that the user must take note. Provides users with helpful suggestions.Example: This menu option only works if a valid LTE analysis has occurredon the current data capture.LitePoint IQdebug User’s GuideUsed for warning the user of potential loss of some sort. The user must be careful not to perform something that results in equipment damage or loss of data.Example: Changing the IP address or the subnet mask may affect the Network Address and the Broadcast Address.Indicates potential danger in operating the equipment. Users must use caution while operating the equipment.Example: This application must be used only by administrators who are highly technical and who have experience using such systems.Used for identifying important features or instructions.Example: You can attach the IP address label provided with the unit and attach it to the front of the unit after you have decided on the correct IP address for the instrument.IQdebug ApplicationThe IQdebug application is a software tool to be used in conjunction with one of LitePoint's WLAN and WiMAX test instruments. It provides an easy-to-use graphical user interface to monitor the status of the test instrument.The graphical user interface also gives access to the basic control and measurement capabilities of the WLAN test instruments. Figure 1 shows the main IQdebug Application window.The application provides the following operating modes:∙Monitor mode∙Control modeThe Monitor mode, which is the default mode, provides an overview of the test system status while running other applications. This mode allows you to debug applications that are being developed with the IQview, IQmax or IQflex tester. For example, it allows you to debug an application while single-stepping through the application code. Using this mode, you can monitor data captures, RF and power levels.The Control mode is used to manipulate basic settings of the connected test system. This includes controlling the settings for the VSG and VSA, such as RF frequencies, RF input amplitude, RF output power level, loading waveforms to the VSG and performing data captures using the VSA.Figure 1. IQdebug User InterfaceLaunching IQdebugTo launch the IQdebug application, go to Start>All Programs><LitePoint Application>>IQdebug<LitePoint Application>represents either the IQmax, IQflex or IQview application.When you launch the IQdebug application, the main screen displays. Figure 2 shows the IQdebug main screen.ABCDEFGHIJFigure 2. Description of IQdebug User InterfaceThe legend for Figure 2 is as follows:A.Menu barB.Dialog box to enter IP address of the test systemC.Operating modesD.VSA controlsE.VSG controlsF.Main output windowG.Data capture outputH.Tester monitor update modesI.Time/spectrum output windowJ.Time/spectrum analysisIQdebug Menu BarThe IQdebug menu bar has the following menus:∙File∙Edit∙Wave∙Analyze∙Update∙HelpFile MenuThe File menu allows you to view the default setup and load, save and print configurations. Figure 3 displays the submenus from the File menu.Figure 3. File MenuThe submenus in the File menu and the description for each submenu are as follows:∙Default Setup—returns to default test system settings; used only in Control mode∙Load Setup—allows you to load previous settings of the test system that have been saved using File>SaveSetup; used only in Control mode∙Save Setup—allows you to save current settings of the test system; you can retrieve the settings using Load>Setup ∙Save Wave—allows you to save the wave data from the most recent capture in *.mat format∙Save Wave ASCII—allows you to save captured data in a *.csv (Comma Separated Value) format to be imported intoa spreadsheet∙Printer Setup—allows you to set printer settings∙Print—allows you to print the plots∙Exit—allows you to exit the IQdebug applicationEdit MenuThe Edit menu has only one submenu—Copy Spectrum. Figure 4 displays the submenu for the Edit menu.Figure 4. Edit MenuEdit>Copy Spectrum copies the screenshot of the main application window to the clipboard for use in other applications. Wave MenuThe Wave menu allows you to open a stored wave file or a predefined wave file. Figure 5 displays the submenu items for the Wave menu. To open a stored wave file, go to Wave>Open any wave file, navigate to the directory where the wave files are stored and select a file you wish to open. The available file formats are *.mod or *.mat. To open a predefined wave file, go to Wave and select one of the predefined wave files from the drop-down list.Figure 5. Wave MenuAnalyze MenuThe Analyze menu allows you to analyze wave information in time and spectrum domain. Figure 6 displays the submenu items for the Analyze menu.Figure 6. Analyze MenuTo receive basic waveform power measurements in time domain, go to Analyze>Basic wave info.To analyze spectral wave information, go to Analyze>Spectrum.Update MenuThe update menu allows you to copy the calibration file to the host PC. Figure 7 displays the submenu items for the Update menu. To copy the calibration file to the host PC, go to Update>Copy Calibration file to PC.Figure 7. Update MenuHelp MenuThe Help menu provides information about the IQdebug software. Figure 8 displays the submenu items for the Help menu. To obtain information about the IQdebug software, go to Help>About.Figure 8. Help MenuConnecting to a Test SystemYou must connect the IQdebug application to the test system in order to use it to capture data. To connect to a test system, enter the IP address of the test system, select the desired mode of operation and click Connect. Figure 9 shows the controls needed for this operation.Figure 9. Controls for Connecting to a TesterBy default, the IP address of the test system is set to 192.168.100.254. The IP address of the test system can be changed using the administration tool supplied with the test system.Perform the following actions to connect to the test system:1.Turn the test system on and make sure the LED is green.2.Enter the IP address of the test system, select the operating mode and click Connect.∙Refer to the Selecting the Operating Mode section to select an operating mode.∙In a local network, the IP addresses of the test system and the host PC should both be in the same range. For instance, if the IP address of the tester is 192.168.100.23, and the IP address of the hosting PC is 10.10.241.1, then a connectioncannot be made. However, if the IP address of the tester is 192.168.100.23, and the IP address of the hosting PC is192.168.100.24, then a connection will be made if the test system is accessible via the network connection and if it ispowered on.Figure 10 shows an established connection between the host PC and the test system.Figure 10. Connecting to a TesterIf the test system is not accessible via the network connection or is not powered on, the connection cannot be made. This is represented in Figure 11.Figure 11. Host PC Not Connected to TesterIf the host PC cannot make a connection to the test system, the main output window indicates that the host PC could not connect to the test system. This is represented in Figure 12.Figure 12. Connection Status WindowReset is used to get the test system and the IQdebug application into a known state after a connection has been established. If you attempt to connect to a different test system using the IQdebug application, you must reset the test system. This refreshes the test system calibration. Reset works only in Control mode.Refer to the Selecting the Operating Mode section for information on the two different operating modes.During a reset, the VSG window displays a red status bar indicating that the application is busy. Figure 13 shows a representation of a system being reset.Figure 13. VSG Control status bar during resetWhen you connect to a different test system, you can use the calibration data of the test system you are connected to by selecting Update>Copy Calibration file to PC in the menu bar. After you make this selection, the calibration file of the test system you are connected to is used for calibration.Selecting the Operating ModeThe IQdebug application allows you to select one of two operating modes:∙Monitor (default)∙ControlMonitor ModeWhen a LitePoint IQview, IQmax or IQflex application is connected to a test system, the Monitor mode allows you to monitor the status of the following items in the test system:∙VSA Setup Information∙VSG Setup Information∙Test System Data Capture BufferFor example, if you are using IQapi to modify the settings on the test system, you can use the IQdebug application in Monitor mode to view the status of the test system. Figure 14 shows the Monitor mode selection.Figure 14. Selecting Monitor ModeThe Update Tester Monitor controls can only be used in Monitor mode and are used to specify if update of information in the main output window is performed once or continuously. Figure 15 shows the Update Tester Monitor controls. Click Once to update the data and receive it once and click Continuous to receive a continuous stream of updated data.If the IQdebug application is set to Continuous mode for a long time, it will impact the test system execution speed and willadd description of the information in the output window.Figure 15. Updating Tester MonitorControl ModeThis mode allows you to take control of the tester settings, change the VSG and the VSA settings, as well as perform data captures. Figure 16 shows the Control mode selection.Figure 16. Selecting Control ModeWhen you actively monitor a tester, the output information is displayed in the main output window and in the data capture output window. This is represented in Figure 17 and Figure 18.Figure 17. Debug Information for Connected tester Figure 18. Data Capture Output WindowControlling the Test InstrumentThe IQdebug application allows you to set the various VSA and VSG parameters in control mode.Changing VSA Settings in Control ModeYou can set the following parameters from the VSA Control section:∙VSA RF Port∙VSA Frequency∙VSA Input Amplitude∙VSA Baseband Gain∙VSA Trigger Mode∙VSA Amplitude Mode∙VSA Input SelectionYou can also perform an Automatic Gain Control (AGC) operation. Refer to the section on Automatic Gain Control for more information on how to set the parameter.The IQflex test system does not support baseband operations.Figure 19. VSA Control SettingsVSA RF PortThe VSA RF port drop-down menu is used to select the RF port to which the VSA is connected.The VSA RF port drop-down menu contains the following items:VSA OFF—indicates that RF port is turned offVSA on 1—indicates the left RF portVSA on 2—indicates the right RF portThe VSA can be connected to either the left or the right RF port. If the VSA is connected to the left RF port, then the VSG is connected to the right RF port.Figure 20. Selecting VSA RF portVSA FrequencyEnter the valid input carrier frequency for the VSA in the VSA Frequency dialog box.Make sure that the baseband input checkbox is not selected.The frequency can be set in the 2.4 GHz, 3 GHz (IQmax only) and 5 GHz bands. Refer to the instrument’s documentation for valid ranges.VSA Input AmplitudeEnter the valid input amplitude, in dBm, to manually set the VSA RF input amplitude. Refer to the instrument’s documentation for valid ranges.VSA Baseband GainUse the VSA baseband gain to adjust the variable-gain amplifier input gain when using the baseband input selection. The variable-gain amplifier input gain is fixed when you use the RF input selection.Make sure that the baseband input checkbox is selected.VSA Trigger ModeThe VSA Trigger Mode is used to select the desired trigger mode. In RF input mode, all available selections are valid. In baseband input mode, only Free Run and External trigger selections are valid.The following figure shows the Trigger Mode Selection menu.Figure 21. Trigger Mode SelectionsThe descriptions for the trigger modes are as follows:Free Run—no trigger handling is applied and data is captured immediately after being initiatedExternal Trigger—data is captured when a trigger signal is applied to the external trigger input portNot all test systems have the external trigger ports.IF level—signal-level variations at the RF input port are used for triggering. In this mode, internal trigger circuitry of the test system is calibrated on every data capture. This will affect the speed of data capture.IF level NoCal—signals applied to the RF input port are used for triggering. In this mode, the internal trigger circuitry of the test system is not calibrated unless gain-stage adjustments are performed in the tester.For the IF level and IF level NoCal modes, the amplitude of the input signal must match the amplitude setting of the signal source. This, for instance, can be achieved by applying the AGC in Free Run trigger mode prior to performing the data capture in the IF level trigger mode.VSA Amplitude ModeThe VSA Amplitude Mode selection is used to switch between two modes that affect the reported VSA amplitude level. The actual gain settings in the VSA are not affected.The two VSA amplitude modes are as follows:∙Average Amplitude Mode∙Peak Amplitude ModeFigure 22. VSA Amplitude Mode SelectionsAverage Amplitude mode—the reported amplitude is the average signal powerPeak Amplitude mode—the reported amplitude is the peak power of the input signal, assuming that the input signal is an OFDM signalVSA Input SelectionWhen you select the VSA Baseband Input check box, the application allows you to select the input source either from the RF ports or from the baseband ports. When you select the check box, the application captures the data from the baseband input ports; if you do not select the checkbox, the application captures the data from the RF input ports.If the VSA frequency settings are valid, the color of the screen does not change. If the VSA frequency settings are notvalid, the screen background color changes to red, as shown in the figure below.Figure 23a. VSA Settings with No Error Figure 23b. VSA Settings with ErrorVSG Settings in Control ModeYou can set the following parameters from the VSG control section: ∙VSG RF Port∙VSG Frequency∙VSG Tx Power∙VSG Sine Wave Generator Frequency∙VSG Sine Wave Generator Enable∙VSG Output SelectionBaseband operation does not apply to the IQflex test system.Figure 24. VSG Control settings VSG RF portThe VSG RF port drop-down menu contains the following items:VSG OFF—indicates that RF port is turned offVSG on 1—indicates the left RF portVSG on 2—indicates the right RF portFigure 25. Selecting VSG RF portVSG FrequencyEnter the valid input carrier frequency for the VSG in the VSG Frequency dialog box.Make sure that the baseband output checkbox is not selected.The frequency can be set in the 2.4 and 5 GHz bands at a resolution of 1 MHz. Refer to the instrument’s documentation for valid ranges.VSG PowerEnter a valid RF transmit output power level, in dBm, in the VSG Tx Power dialog box. The assumed load is 50Ω. R efer to the instrument’s documentation for valid ranges.VSG Sine Wave Generator FrequencySelect the Sine Wave check box to enable the sine-wave signal generator. The generated sine wave will be modulated on to the output signal. The VSG generator frequency is used to set the modulation frequency in MHz. When the Sine Wave check box has not been checked, a signal that is generated from a modulation file will be used.VSG Sine Wave Generator EnableThe VSG output can either be an RF output or a baseband output. For modulation using baseband output, select the Baseband Output checkbox. For modulation using RF output, make sure that the Baseband Output checkbox is not selected.Using VSG Wave Files in Control ModeThe IQdebug application allows you to modulate data from wave files onto the output signal at the transmitter port. The Wave menu allows you to open a stored wave file or predefined wave files.To open a stored wave file, in the menu bar, go to Wave>Open any wave fileTo open a predefined wave file, in the menu bar, go to Wave and select a wave file.Make sure that the VSG Sine Wave checkbox is not selected when you open a stored wave file or select a predefined wave file.Screen Background ColorThe VSG screen background color differs based on the VSG settings.The screen colors displayed and the description are as follows:Gray—if all VSG settings are correctRed—if the VSG frequency is set outside the valid range, or if the VSG output power level is too high. If the VSG output power is too high, the signal may get compressed.Yellow—if the VSG output power level is too low. If the VSG output level is too low, the signal to noise ratio would decrease.Figure 26a. Correct Settings Figure 26b. Frequency Not Valid Figure 26c. Low Output PowerPerforming Data Captures in Control ModeIn Control Mode, you can perform data captures by clicking either one of the three buttons shown in the figure below.Figure 27. Buttons for Performing Data CapturesThe three buttons allow you to capture different amounts of samples:0.200 ms—captures 200 μsec of samples1.000 ms—captures 1 msec of samples10.000 ms—captures 10 msec of samplesThe figure below shows the Data Capture Output window for the I and the Q channels plotted against time. The blue plot represents the I channel, and the green plot represents the Q channel.Figure 28. Data for I and Q channelThe color of the status bar indicates the following:Gray—successful data capture.Red—data is being captured; application is busyYellow—clipping has occurred in the digital domain of the VSAOrange—trigger time-out has occurred or the application has been disconnected from the test system before performing the data captureFigure 29a. Successful Data Capture Figure 29b. Application is BusyFigure 29c. Clipping in VSA Figure 29d. Trigger Time-OutAutomatic Gain Control in Control ModeThe AGC button allows you to apply Automatic Gain Control. This button allows you to automatically set the optimum gain for the present input signal, and performs data capture. AGC is performed by taking several measurements, and then adjusting the individual gain stages of the test system. After the gain stages have been adjusted, the system performs the actual data capture.Figure 30a. AGC Operation Successful Figure 30b. AGC in Operation Figure 30c. AGC Fails Gray—AGC operation was successfulRed—AGC is being performedOrange—One of the following reasons:- AGC fails- input signal is too low and AGC is out of range- trigger times out; for example, if the external trigger has been enabled and no trigger signal is present- if the connection to the test system is disrupted before performing AGCPower Versus Time DisplayYou can toggle between showing the I and Q channel data in the data capture output window and showing the data as power versus time using the dB button. The I channel data is shown in blue, and the Q channel data is shown in green.Figure 31. Showing the Power Versus Time of the Captured DataZoomYou can zoom in the data capture output window by dragging the mouse. Figure 32 shows the process of zooming in on the data capture.Figure 32. Zooming in on Captured DataAnalysisThe data can be analyzed in one of two ways:∙Wave Information in the Time domain∙Spectrum InformationWave Information in the Time DomainThis analysis type shows basic power measurements in the time domain.To analyze wave information in the time domain, you can do one of the following:∙In the main menu, go to Analyze>Basic Wave Info∙Click Time in the left pane. See Figure 33.∙Click Time in the right pane. See Figure 34.Figure 33. Selecting Analysis Type from Left Pane to Perform AnalysisFigure 34. Selecting Analysis Type from Right Pane to Show Analysis ResultsThe analysis data displays in the main output window. An example of the output window is shown in Figure 35.The descriptions of parameters in the figure below are as follows:DC—DC level for I and Q signalsrms—Root Mean Square (rms) voltage for I and Q and combined signalmin—minimum voltage levelmax—maximum voltage levelFigure 35. Sine Wave Information in Time DomainSpectrum InformationSpectral analysis shows the measured frequency spectrum. The X-axis indicates the frequency offset from center frequency and the Y-axis indicates the signal power. If the RF ports are used for input, then the signal power is measured in dBm; if the Baseband port is used for input, then the signal power is measured in dBV. An example of the spectrum analysis of an OFDM signal is shown in Figure 36.Baseband operation is not applicable for the IQflex tester.To select spectral analysis, you can do one of the following:∙In the main menu, go to Analyze>Spectrum∙Click Spectrum in the left pane. See Figure 36.∙Click Spectrum in the right pane. See Figure 37.Figure 36. Spectrum of CW SignalAn example of the spectrum analysis of a Continuous Wave (CW) signal is shown in Figure 38.When analyzing an OFDM package, you can zoom the preamble portion. An example of this is shown in Figure 37.Figure 37. Preamble of OFDM SignalAn analysis has to be performed first using left pane buttons, before valid results are shown on the right pane using buttons in the right pane.DisclaimerLitePoint Corporation reserves the right to make this product available for sale and make changes in specifications and other information contained in this document without prior notice! LitePoint Corporation makes no warranty of any kind with regards to this material, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. LitePoint shall not be liable for errors contained herein or for material or consequential damages in connection with the furnishing, performance, or use of this material.No part of this manual may be reproduced or transmitted in any form or by any means without the written permission of LitePoint Corporation. Contact your local sales representative for latest information and availability. The information furnished by LitePoint Corporation is believed to be accurate and reliable. However, no responsibility is assumed by LitePoint for its use. LitePoint reserves the right to change specifications and documentation at any time without notice.LitePoint and the LitePoint logo, IQview IQflex, IQnxn, and IQmax are registered trademarks and IQsignal, IQwave, IQfact, IQcheck, IQdebug, IQmeasure, IQtest, IQexpress, IQturbo, IQultra, TrueChannel, and TrueCable are trademarks of LitePoint Corporation. Microsoft Windows is a registered trademark of Microsoft Corporation in the United States and/or other countries. All trademarks or registered trademarks are owned by their respective owners. © 2008 LitePoint Corporation.LitePoint Corporation - Corporate Headquarters。