Spirent Communications Nomad User’s Manual Spirent Communications 7340 Executive Way Suite A Frederick, MD 21704 Document Version: 3.
Nomad User’s Manual Notice: The Bluetooth word mark and logos are owned by the Bluetooth® SIG, Inc. and any use of such marks by Spirent Communications, Inc. is under license. Other trademarks and trade names are those of their respective owners. Notice: NOTE: This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules.
Nomad User’s Manual Contents 1 Introduction ..................................................................................................................................................................... 7 2 Nomad System Configuration ................................................................................................................................... 9 2.1 System Component Verification...................................................................................................
Nomad User’s Manual 5.2.2 5.2.2.1 7 Channel Settings........................................................................................................................................ 41 5.2.4 Call Campaign ............................................................................................................................................. 44 5.2.5 Auto-Level Assist .............................................................................................................................
Nomad User’s Manual 8.10 Troubleshooting Incomplete Data ........................................................................................................... 103 8.11 Offline Scoring (Voice Quality Testing) .................................................................................................. 106 8.11.1 Creating a New Logging Session Using Offline Scoring .......................................................... 107 8.11.
Nomad User’s Manual Appendix F – Nomad HD Hardware............................................................................................................................ 156 Important Safety Note ................................................................................................................................................. 156 Nomad HD LEDs ...................................................................................................................................................
Nomad User’s Manual Chapter 1 – Introduction 1 Introduction Spirent Communications Nomad provides a comprehensive and efficient measure of real-world mobile device performance by automating high-volume call control testing sequences and voice quality characterization on virtually any Bluetooth-enabled handset, regardless of wireless technology or device model.
Nomad User’s Manual Chapter 1 – Introduction The metrics available as outputs from the Nomad system include: Voice Quality (Uplink and Downlink) Voice Delay Call Initiation Performance (Mobile Originated and Mobile Terminated Calls) Call Retention Performance (Mobile Originated and Mobile Terminated Calls) Call Setup Time Loss of Network Bluetooth Voice Performance This document describes the setup and operation of the Spirent Nomad system for all voice quality, Bluetooth and call performa
Nomad User’s Manual Chapter 2 – Nomad System Configuration 2 Nomad System Configuration The Spirent Communications Nomad system contains both hardware and software for mobile performance evaluation. Prior to installing Nomad for the first time, please verify that all hardware components are present, including a laptop meeting the Nomad computing requirements. Also note that when setting up the Nomad system for the first time, the software must be installed prior to connecting the hardware.
Nomad User’s Manual Chapter 2 – Nomad System Configuration Computing Requirement Processor RAM Free Disk Space Operating System USB Drive Software Optimal Performance Intel® CoreTM i7 8 GB 20 GB Windows XP, Vista or 7 N/A N/A Dedicated High Speed Internet Connection N/A Copyright © Spirent Communications, Inc. 2013 Minimal Performance Intel® CoreTM i5 4 GB 10 GB Windows XP USB 2.0 Drive Microsoft .NET Framework 3.5 SP1 (See Section 2.1.
Nomad User’s Manual Chapter 2 – Nomad System Configuration 2.1.1 Microsoft .NET Framework 3.5 SP1 The Nomad software application requires Microsoft .NET Framework 3.5 SP1. Although the Nomad software installation includes Microsoft .NET Framework 3.5 SP1, Spirent Communications recommends performing a manual check for this component. To verify the current version of Microsoft .
Nomad User’s Manual Chapter 2 – Nomad System Configuration 2.1.2 Disable User Account Control (Windows Vista and Windows 7) The Nomad software application requires that the User Account Control (UAC) setting be disabled on Windows Vista and Windows 7 machines. To disable UAC in Windows Vista: From the Windows Start menu select Settings → Control Panel. Under User Accounts and Family Safety select Add or remove user accounts.
Nomad User’s Manual Chapter 2 – Nomad System Configuration Figure 2-3 - Make changes to your user account Deselect Use User Account Control (UAC) to help protect your computer. Figure 2-4 - User Account Control Screen Click OK to confirm your selection. When prompted, restart your computer to apply the changes. To disable UAC in Windows 7: From the Windows Start menu select Settings → Control Panel. Under User Accounts and Family Safety select Add or remove user accounts.
Nomad User’s Manual Chapter 2 – Nomad System Configuration Click the User Accounts link. Figure 2-6 - User Accounts Area In the list of user account options, select Go to the main User Accounts page Select the Change User Account Control Settings option. Figure 2-7 – Make changes to your user account Screen Lower the notification bar from Always notify to Never notify. Figure 2-8 - User Account Control Screen Click OK to confirm your selection.
Nomad User’s Manual Chapter 2 – Nomad System Configuration 2.2 Software Installation The Nomad installation file may be obtained from your Spirent Communications representative. Once you have the Nomad installation package: Unzip the package (if applicable) and click on Setup. Follow the instructions to complete the software installation.
Nomad User’s Manual Chapter 2 – Nomad System Configuration 2.3 Hardware Installation Figure 2-10 - Spirent Communications ME and HD ME Hardware Units Configure the Spirent ME or Spirent HD ME hardware by making the following connections: Plug in the AC Adapter and connect to the +12V port on the Spirent Nomad unit. Connect the GPS Receiver to the GPS port.
Nomad User’s Manual Chapter 3 – Application Workflow 3 Application Workflow This section provides an overview of the Nomad workflow: Open the program Specify Nomad settings Define the test by assigning tasks to channels and modifying task settings Initiate the test Monitor the test in progress Analyze the results The testing process is illustrated in Figure 3-1. The following sections of this document describe the detailed procedures used in working with Nomad.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings 4 Specifying Nomad Settings Prior to first use, Nomad must be configured with user preferences. Configuring the program consists of: Specifying General Settings Specifying GPS / Time Settings Specifying Call Performance Settings Specifying Voice Quality Settings Specifying Email Campaign Settings Each of these configuration options is accessible from the Nomad Settings tab.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings 4.1 Specifying General Settings To specify general settings for Nomad on the General settings tab: Choose whether to Check for updates on application startup to determine whether a newer version of Nomad is available (recommended). Choose whether to Check for new utilities on application startup to check for newer versions of installed utilities and to find new utilities (recommended).
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings 4.2 Specifying GPS/Time Settings Specify settings related to time synchronization and GPS on the GPS/Time tab. The Automatic Time Synchronization and GPS areas are discussed in detail below. Figure 4-3 - GPS/Time Settings 4.2.1 Time Synchronization The successful use of the Nomad system is strictly dependent on consistent timing between the test laptop and the Audio or Call Server.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings Check Enable automatic time synchronization to prevent time drift in synchronization between the test laptop and the Voice or Call Server. This option requires that you have access to the time synchronization source (internet or GPS) during testing. Set the period between time synchronization updates in minutes. Spirent recommends setting this to 5 minutes for frequent updates.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings 4.3 Specifying Call Performance Settings Specify settings related to Call Performance testing on the Call Performance tab. The different areas of this tab are discussed in detail below. Figure 4-4 - Call Performance Settings 4.3.1 Call Server In the Call Server area, select the geographically relevant Call Server.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings 4.3.2 Logging Session Auto-Stop Spirent provides the ability to automatically stop the entire logging session if the number of consecutive Bluetooth connection errors on any test device exceeds the provided threshold. This check ensures that a user does not conduct an extended test using a non-functioning device, possibly invalidating results for the entire test array.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings Figure 4-8 – CDR Lookup area Copyright © Spirent Communications, Inc.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings 4.3.5 Call Result Warnings Select whether or not to Enable call result warnings and to Enable audible alarms for these warnings. Warnings will occur when the consecutive number of events exceeds the user-defined threshold for each of these event types: Call Outcome Failed Attempt Definition A Mobile Originated Call was placed and an outgoing call was established followed by the phone’s return to the call placement state.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings 4.4 Specifying Voice Quality Settings Specify settings related to Voice Quality testing on the Voice Quality tab. The different areas of this tab are discussed in detail below. Figure 4-10 - Voice Quality Settings 4.4.1 MOS Thresholds Use the settings in the MOS Thresholds area to customize data views according to local performance criteria: Copyright © Spirent Communications, Inc.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings Figure 4-11 - MOS Thresholds Area Copyright © Spirent Communications, Inc.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings Use the Color Bar to set the thresholds that determine Great (green), Good (yellow) and Bad (red) voice quality performance. Check Collect X random WAV sample(s) from each MOS range above at the end of each session to set aside a random sample of audio files within each MOS performance range. This allows the audible verification of Great, Good and Bad audio samples at the conclusion of the test. See Section 8.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings 4.4.4 Audio Server The Audio Server facilitates voice quality testing by answering calls, sending and recording .WAV files, storing the recorded .WAV files and handling uplink data collection. The Audio Server is an extremely high quality Interactive Voice Response (IVR) service provided by Spirent Communications to answer calls, send and record speech, and store the recorded samples for access to uplink results.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings 4.4.7 Default Scoring Algorithm This setting controls the default scoring algorithm for each new voice quality task added to a Nomad channel. Either PESQ or POLQA may be selected. See Appendix E for an introduction to POLQA including a comparison between PESQ and POLQA. The default scoring algorithm may be overridden for any individual task when modifying the task settings. Figure 4-16 - Default Scoring Algorithm Area 4.
Nomad User’s Manual Chapter 4 – Specifying Nomad Settings Check the Override default email content box to specify the content of the body of the emails to be sent to the phone during an email campaign. If this box is left unchecked, Spirent will automatically generate the content for the messages sent in the email campaign. Copyright © Spirent Communications, Inc.
Nomad User’s Manual Chapter 5 – Defining a Test 5 Defining a Test Nomad provides testing flexibility with a fully configurable Test Setup utility. Users may customize the type of task to be performed on each test channel (per availability based on licensing) as well as task details. When defining a test it is necessary to: Assign tasks to channels Modify task settings Save test settings All test definition options are available from the Test Setup tab and are discussed in the following sections.
Nomad User’s Manual Chapter 5 – Defining a Test 5.1 Assigning Tasks to Channels Three different methods are available for assigning a new task to a channel: 1. Drag and drop any Voice Quality Task or Call Performance Task onto an available Test Channel. 2. Right-click on an individual channel and select Add Task. Then select the type of task to add from the sub-menu. 3. Right-click on a task name and select the channel(s) to apply to.
Nomad User’s Manual Chapter 5 – Defining a Test 5.1.1 Voice Quality Tasks The following voice quality task types are available for selection: Figure 5-3 - Voice Quality Task Types Mobile o The test device on a Mobile channel serves as the downlink device in the mobile communication path. This option is used for: Standard bi-directional testing using the Audio Server. (See Section 9.
Nomad User’s Manual Chapter 5 – Defining a Test Mobile Originated o The mobile test device makes calls to the Call Server for call control testing. (See Section 10.1) Mobile Terminated o The Call Server makes calls to the test mobile for call control testing. (See Section 10.2) Idle o The test device makes no calls. This type of task only reports changes in signal strength and battery level.
Nomad User’s Manual Chapter 5 – Defining a Test 5.2 Modifying Task Settings Each assigned task must be configured with specific task settings. Click any available channel to modify its configuration. Different types of settings area available for different task types.
Nomad User’s Manual Chapter 5 – Defining a Test 5.2.2 Session The fields in the Session dialog specify connection settings for a Voice Quality Task. This dialog is not used for Call Performance Tasks. Some settings available in this dialog depend on the type of Voice Quality Task to be performed: Figure 5-7 - Session Dialog Device Selection Area – Any Nomad Voice Quality Task is dependent on the transmission of speech between two communication nodes.
Nomad User’s Manual o o o Chapter 5 – Defining a Test Downlink Device – In a Base task, the test device serves as the uplink device in the mobile communication path. Select the Downlink Device to handle downlink data collection and uplink audio sourcing. Mobile Task on Remote Unit – Use this option to configure bi-directional Remote Unit testing. In this test case, the mobile on one Spirent ME unit is configured with a Mobile task while the mobile on the other unit is configured with a Base task.
Nomad User’s Manual Chapter 5 – Defining a Test Figure 5-8 – Edit Audio Server Settings Dialog o o o o o Dial the Audio Server using the handset to be connected to this channel. The handset does not need to be connected at this time. All active calls to the Audio Server will be represented in the Connection Assistant drop-down window using the {4 Digit DNIS}-{10 Digit ANI} convention: {4 Digit DNIS} –The last four digits of the Audio Server phone number called by the mobile.
Nomad User’s Manual Chapter 5 – Defining a Test Figure 5-10 – Phone Number Settings Populated by the Connection Assistant Reference file o This setting controls the reference file to be used for this voice quality task. This is an advanced setting which, when changed from the default value, will not work with any of Spirent’s default call servers, only when a corresponding ‘base’ task hase been setup up on a second Nomad unit.
Nomad User’s Manual Chapter 5 – Defining a Test Figure 5-12 – Reference file Settings IMS Server Information – The following fields are related to the server on which the Device Under Test is registered.
Nomad User’s Manual Chapter 5 – Defining a Test sampling rates per channel pairs. The channel pairs are 1&2 and 3&4. Thus, if channel 1 is set to Narrowband, channel 2 cannot be set to High Definition. Sampling Rate – The Sampling rate for audio associated with this channel. Scoring Model – The MOS scoring algorithm used to score audio.
Nomad User’s Manual Chapter 5 – Defining a Test With this configuration, a call that is dropped during testing will be redialed using the Bluetooth connection. After three cycles of silence, Nomad will then issue a command to transfer the audio from the Bluetooth to the analog connection. Copyright © Spirent Communications, Inc.
Nomad User’s Manual Chapter 5 – Defining a Test 5.2.4 Call Campaign The fields in the Call Campaign dialog are used to specify duration and sequencing of a Call Performance Task. This dialog is not used for Voice Quality Tasks. All of the fields in this dialog must be completed. Figure 5-14 - Call Campaign Dialog (Mobile Originated Task) Enter the Phone Number Settings.
Nomad User’s Manual Chapter 5 – Defining a Test Specify the values for the task parameters. In the Mobile-to-Mobile case, these parameters will be set in the Mobile-to-Mobile Originate task. o Access Timeout – A call attempt that has not connected within this amount of time will be classified as an Access Timeout event. o Duration – The length of each call in the test sequence. In a Synchronous campaign, this refers to the total attempt duration including access time and connected time.
Nomad User’s Manual Chapter 5 – Defining a Test 5.2.5 Auto-Level Assist The Auto-Level Assist Wizard provides an automatic method for determining optimal downlink and uplink volume for Voice Quality Tasks running on mobiles connected via the analog audio interface. The Auto-Level Assist Wizard has no bearing on Call Performance Tasks or on Voice Quality Tasks using a Bluetooth connection.
Nomad User’s Manual Chapter 5 – Defining a Test Note: Spirent strongly recommends that international users outside of North America use the Connection Assistant to ensure that phone numbers are entered in the correct format. Click Next to continue. o Figure 5-16 - Auto-Level Assist Phone Number Validation You will be asked whether you wish to check for uplink connectivity to verify communication with the server. Click Yes to verify.
Nomad User’s Manual Chapter 5 – Defining a Test The system will make three attempts to contact the Audio Server. When connectivity is verified, the level assist automation will begin. Figure 5-18 - Auto-Level Assist Audio Server Connectivity Verification The auto-calibration process will run for several minutes displaying MOS progress as volume is adjusted.
Nomad User’s Manual Chapter 5 – Defining a Test After the Auto-Level Assist Wizard has run its course, the Results Review dialog will appear. Examine the downlink and uplink results for each channel. Select whether to use the saved level setting or the Level Assist recommendation. Click Next to store selections.
Nomad User’s Manual Chapter 5 – Defining a Test 5.2.6 Email Campaign An Email Campaign may be launched during a Voice Quality or Call Performance task to test Multi-RAB performance. An Email Campaign tests whether email sent to the phone during a call disrupts performance as compared to phones not receiving email. An email campaign may be launched from the Email Campaign dialog.
Nomad User’s Manual Chapter 5 – Defining a Test 5.2.7 Bluetooth Connection Use the Bluetooth Connection screen to perform pairing of the test device with the Spirent ME hardware unit. The Bluetooth Connection dialog will be available for any Voice Quality Task with the Audio Interface set to Bluetooth. The Bluetooth Connection dialog will be available for all Call Performance Tasks. Figure 5-22 - Bluetooth Connection Dialog To pair a device: Click the Start Pairing button.
Nomad User’s Manual Chapter 5 – Defining a Test 5.2.8 Reconnect All Bluetooth Channels The Reconnect All Bluetooth Channels button will be available for voice quality tasks with the Audio Interface set to Bluetooth and for all Call Performance tasks. Click this button to reconnect all previously connected Bluetooth channels to the last paired handset. Copyright © Spirent Communications, Inc.
Nomad User’s Manual Chapter 5 – Defining a Test 5.3 Saving Test Settings Once tasks have been assigned to all test channels and settings for all tasks have been configured to meet testing requirements, it may be desirable to save these settings for future use.
Nomad User’s Manual Chapter 5 – Defining a Test 5.3.1 Working with Configured Tasks A Configured Task saves all of the settings for the currently selected task. A Configured Task may then be applied to any test channel in the current or future tests. This option is useful for replicating a single task across multiple test channels. To save a Configured Task: Configure all task settings as desired. Select the Save As Configured Task option on the Test Setup tab.
Nomad User’s Manual Chapter 5 – Defining a Test Two methods are available to apply the task to any specific channel or All Channels: 1. Use the Apply selected task to: drop-down at the bottom of the dialog. Then click OK to confirm the selection. 2. Right-click on the selected task and select Apply To and the channel number. The Configured Tasks dialog will close automatically. Figure 5-26 - Applying the Selected Task A Configured Task may be exported as an XML file to share with other users.
Nomad User’s Manual Chapter 5 – Defining a Test 5.3.2 Working with Profiles A Session Profile defines the tasks and settings for all available test channels. Unlike a Configured Task which defines a task type and settings for an individual task, a Session Profile defines the task type and settings applied to each test channel. To save a Session Profile: Configure all desired test channels with tasks and settings to meet testing requirements.
Nomad User’s Manual Chapter 5 – Defining a Test Figure 5-28 - Select a Saved Session Profile Click the Load Selected Session Profile button in the bottom right corner of the dialog. Each test channel configured in the Session Profile will be populated on the Test Setup tab. A Session Profile may be exported as an XML file in order to share with other users using the Export Session Profile button in the Saved Session Profiles dialog.
Nomad User’s Manual Chapter 6 – Initiating a Test 6 Initiating a Test Once a task has been assigned to each Nomad test channel and task settings have been configured, a test session may be initiated. To start a test: Click the Start Logging Session button on the Test Setup tab. The Start Logging Session Wizard will appear. The following sections describe each step in the Wizard. 6.
Nomad User’s Manual Chapter 6 – Initiating a Test Figure 6-2 - Bluetooth Module Device Control 6.3 Placing Calls on Mobile Handsets At the conclusion of the Start Logging Wizard, Nomad will automatically place test calls for: All devices running Call Performance tasks. Devices running Voice Quality tasks which are connected via Bluetooth and which have been configured for auto-dial on the Settings → Voice Quality tab (see Section 4.4.3). All other calls must be manually placed to the Audio Server.
Nomad User’s Manual Chapter 6 – Initiating a Test 6.4 Selecting the Log File Storage Location To specify the log file storage location and other session information: In the File Path area use the Browse button to select a log file location and file name. This field is required. Complete the User Name, Route/Location and Description fields as desired. This information serves as optional metadata written to the session log file. Click Next to continue.
Nomad User’s Manual Chapter 6 – Initiating a Test Figure 6-4 - Attempting to Synchronize Time If neither GPS nor internet connectivity is available, synchronization will fail. Although the Start Logging Session button becomes available on the Failed Synchronization screen, Spirent recommends troubleshooting GPS and/or internet connectivity and then retrying. Running a logging session without verifying time synchronization is not recommended and may result in invalid data.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress 7 Monitoring a Test in Progress Topics of interest while a test is in progress include: Nomad Test Window Orientation Manual Volume Adjustment (Voice Quality Testing) Event Logging and Event Detection (Voice Quality Testing) Interpreting MOS Results (Voice Quality Testing) 7.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress B. Current Time Indicator The radio button selected here is used to control the time display during testing. o Select UTC to display data collection time in UTC (Coordinated Universal Time), also known as GMT (Greenwich Mean Time). o Select Local to display data collection time according to the test laptop’s local time. The time format selected here is for display purposes only.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress D. Session Duration The elapsed time since the start of the session is displayed here. Figure 7-5 - Session Duration E. Stop Use this button to manually end a test session. Note: Losing internet connectivity during a Mobile Terminated Call Performance campaign may cause the Stop button to cease working. In this case, wait for a call to come to the phone, answer the call and dial 9999.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress Figure 7-8 - Time Sync Dialog G. Settings Figure 7-9 - Settings Button Levels – Use this tab to manually adjust uplink and downlink volume settings for each channel. See Section 7.2 for details on manual volume adjustment. Figure 7-10 - Levels Tab of Test Settings Dialog Copyright © Spirent Communications, Inc.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress Bluetooth – Use this tab to pair, adjust or view information for Bluetooth-connected test devices. See Section 5.2.7 for more information on using the Bluetooth dialog. Figure 7-11 - Bluetooth Tab of Test Settings Dialog Log – This tab provides a log of system events during a Voice Quality task. Figure 7-12 - Log Tab of Test Settings Dialog H. Help This option opens the Online Help file for Nomad.
Nomad User’s Manual I. Chapter 7 – Monitoring a Test in Progress Call Performance Task Status Window (Mobile Originated Task) Figure 7-14 - Call Performance Task Status Window (Mobile Originated Task) Call Performance test status items displayed in this area: o State – The state of the call, typically listed as Waiting, Connecting or Active Call. o Actual Wait Duration – The amount of time the phone has spent in Wait mode. o Connected Duration – The amount of time spent on the call.
Nomad User’s Manual J. Chapter 7 – Monitoring a Test in Progress Call Performance Task Status Window (Mobile Terminated Task) Figure 7-15 - Call Performance Task Status Window (Mobile Terminated Task) Call Performance test status items displayed in this area: o State – The state of the call, typically listed as Waiting for Next Call (Idle), Ringing or Active Call o Connected Duration – The amount of time spent on the call.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress K. Call Performance Statistics Window For Mobile Originated calls, this window displays the current test progress along with Call Performance statistics. For Mobile Terminated calls, only those fields for which data is available at the mobile end will be populated in this window during testing. The remaining fields will display as PENDING during the test.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress L. Voice Quality Task Status Window Status for the current Voice Quality cycle is noted here as one of the following options: o Waiting – This state indicates that the call has been placed midway through one of the Sourcing/Recording cycles. Nomad will remain idle until the start of the next full Sourcing/Recording cycle, at which point data capture will begin. o Recording – In this state, Nomad is currently recording the .
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress Figure 7-17 - Voice Quality Task Status Window M. MOS Trends Window Select Session to view the downlink or uplink measurement history for all handsets performing Voice Quality testing. Figure 7-18 - MOS Session Window Select an individual channel (Channel 1 / Channel 2 / Channel 3 / Channel 4) to view the measurement history for that handset for the current test session. Both the downlink and uplink history will be displayed here.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress Figure 7-19 - Individual MOS Trend Window Select Distribution to view the spread of downlink or uplink MOS values for all handsets in the current test session. Figure 7-20 - MOS Distribution Window The Events tab displays null MOS events automatically detected by Nomad as well as events manually recorded by the user. See Section 7.3 for details on event logging and event detection. Copyright © Spirent Communications, Inc.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress Figure 7-21 - Events Window Copyright © Spirent Communications, Inc.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress 7.2 Manual Volume Adjustment (Voice Quality Testing) Although Spirent recommends running the Auto-Level Assist Wizard (see Section 5.2.5) prior to Voice Quality testing to find optimal downlink and uplink volume settings, manual volume adjustment may be necessary to fine-tune the results. Manual volume adjustment may be used in lieu of Auto Level Assist for analog connections, and must be used in the case of a Bluetooth connection.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress 7.2.1.2 Downlink Volume Adjustment for Analog Connections To manually find the optimal downlink volume for any analog channel using the Levels dialog: For the channel of interest, move the Input Level slider to the far right such that the Overdrive light illuminates in the GUI and a red light appears for that channel on the hardware unit.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress Figure 7-24 - Events Tab Click on the cell corresponding to the cycle and channel of interest. In the Event Classification dialog, select an event to add. Figure 7-25 - Event Classification Dialog The selected event will appear in the cell. Any channel-specific event entry in the event log will replace the MOS entry for that position in the merged output (see Section 8.1).
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress To manually note an event that pertains to all channels at a given timestamp (cycle-specific event): In the Events tab of the MOS Trends Window, click on the Notes column at the timestamp of interest. Enter notes in the Cycle Notes dialog and click OK. The recorded notes will appear in the Event Window and will be added to the summary report created with the merge utility. These notes will not replace MOS values for the affected cycles.
Nomad User’s Manual Chapter 7 – Monitoring a Test in Progress 7.4 Interpreting MOS Results (Voice Quality Testing) Nomad provides audio quality scores using either PESQ P862.1 MOS or POLQA P.863 MOS as selected by the user2. Both standardized models for predictive speech quality utilize speech signals that are subjected to the communications link under test and compare the degraded speech to the original speech.
