Overview |
Automatic Echo Canceller Test Software |
Screenshots |
Automatic Echo Canceller Test Viewer Software |
For Voice Enhancement and Voice Quality Testing |
Buyer's Guide
Overview
The Auto EC Test Software (XX067) is a GL Communications' feature rich application used to perform echo cancellation testing
automatically. Auto EC Test Viewer (AEC001) supplements AutoEC Test software using which the EC test results are analyzed and
graphically viewed.
Automatic Echo Canceller Test Software (Application item# XX067)
The Auto EC Test Software is a feature rich application that uses GL Communications' T1/E1 Analyzer products and the customers EC hardware to perform Automated Echo Canceller testing in accordance with G.168 (01/2007), G.168 (08/2004), G.168 (06/2002), and G.168 (04/2000) ITU test requirements. It can also be used to test development EC software, for which the customer's EC hardware is not required.
Features
- MS-Windows OS (WIN 2000 or XP) with User-Friendly Graphical User Interface
- Compatible with GL's T1/E1 HD Cards and USB portable T1/E1 units
- Real-time as well as off-line analysis
- Simulates an actual echo loop with echo path delay, hybrid filter, and attenuation
- Simulates long haul delay
- Auto analysis of the response according to G.168 (01/2007), G.168 (08/2004), G.168 (06/2002), and G.168 (04/2000) requirement
- Auto or Manual control of the EC during testing
- Tabular Pass/Fail Results
- Simulation of echo path with various delay, attenuation, hybrid filters, noise level, etc.
- Detailed graphical results for individual overall test.
Theory of operation
There are two methods for automated testing of echo cancellers, they are:
File Based Approach - This method transmits files to Sin and Rin of the EC and captures responses at Sout
and Rout. With this method, the Sin (echo signal) is pre-created from the Rin signal. This method assumes that Rout is identical to
Rin. This works perfectly for TDM based Line Echo Cancellers. This could also be used to test ECs within Gateways in VoIP or VoATM
environments as long as the delay between gateways is constant and Rout=Rin is valid. When testing ECs within Gateways, a
configuration of back-to-back Gateways is necessary to access the TDM side of each Gateway.
AutoEC Testing through file based Tx/Rx Utility
Real-Time Approach - This method creates Sin in real-time from the Rout. It is applicable to TDM, VoIP, and
VoATM Networks. Windows Client Server (WCS) Software is used to perform real-time functions. Diagram for real-time approach is
depicted below.
AutoEC Testing through real-time approach
As discussed above, two methods may be used to generate/capture stimulus and response signals from the EC. In the File
Based approach, Rin and Sin files (stimulus and echo) are prepared by Auto EC Test software and then applied to the EC. In the
Real-Time approach, the Sin signal is created in real-time from Rout. In either case, users are permitted to set:
Test # 1 to 15 of G.168(01/2007), G.168 (08/2004), G.168 (06/2002), and G.168 (04/2000) (Test 14 is optional)
- Framing format (D4 and ESF for T1, CAS and CCS for E1)
- Timeslots
- Levels for pseudo speech/noise
- Levels for noise
- Hybrid filter types including multiple echo paths
- Echo path delays and ERL
The software applies the Rin and captures the Sout (the output of the Echo Canceller) Sin may be pre-passed (file based) or
generated in real-time (WCS approach). During the application of Rin and Sin, the Echo Canceller is manually or automatically
controlled for
- Zeroing the contents of the echo canceller's H-register.
- Enabling and inhibiting echo canceller convergence.
- Enabling and disabling the non-linear processor.
- If the echo canceller has a comfort noise feature, enabling and disabling the comfort noise generator.
Rout and Sout files are captured and automatically assessed. Graphical and tabular data is provided for all tests for easy
interpretation. Objective test results are displayed and user can easily identify passed or failed tests. Users can zoom-in on any
test result to further investigate. The detailed graphical analysis of tests is also a click away to gauge overall performance of the
echo canceller.
Using AutoECTest Software (Basic setup without customer's EC hardware)
The AutoECTest Software (xx067) is intended to work with GL hardware (T1 or E1 dual cards) and the customers EC hardware.
But it can also be used to test development EC software, that is, the customer's EC hardware is not required. For more information,
please click here
Test Cases supported
Test 1: Steady state residual and returned echo level test (G.168 version 04/2000 only)
Test 2A : Convergence Test with NLP Enabled
Test 2A Part b: Re-convergence test with NLP enabled (G.168 version 01/2007)
Test 2B: Convergence Test with NLP Disabled
Test 2B Part b: Re-convergence test with NLP disabled (G.168 version 01/2007)
Test 2C: Convergence Test in the Presence of Background Noise
Test 2C-c: Convergence test with NLP disabled (G.168 version 01/2007)
Test 3: Performance under Conditions of Double Talk
Test 3A: Double Talk Test with Low Near End Levels
Test 3B: Double Talk Test with High Near End Levels
Test 3B Part b: Double talk stability test with low cancelled-end levels (G.168 version 01/2007)
Test 3C:Double Talk Test under Simulated Conversation
Test 4: Leak Rate Test
Test 5: Infinite Return Loss Convergence Test
Test 6: Non-Divergence on Narrow-Band Signals
Test 7: Stability Test
Test 8: Non-convergence of Echo Cancellers
Test 9: Comfort Noise Test
Test 10A: Canceller operation on the calling station side
Test 10B: Canceller operation on the called station side
Test 14: Low speed modem test (Optional)
Test 15A and 15B: PCM offset test (G.168 version 2002/2004/2007)
For the G.168 – version 01/2007, the Test cases are as shown in the figure below.
Screen Shot of Setting EC test parameters per G.168 - version 01/2007
For the G.168 – version 08/2004, the Test cases are as shown in the figure below.
Screen Shot of Setting EC test parameters per G.168 - version 08/2004
For the G.168 – version 06/2002, the Test cases are as shown in the figure below.
Screen Shot of Setting EC test parameters per G.168 - version 06/2002
For the G.168 – version 04/2000, the Test is from Test1~Test10B as shown in the figure below.
Screen Shot of Setting EC test parameters per G.168 - version 04/2000
Screenshots
Automatic Echo Canceller Test Viewer Software (Application item# AEC001)
AutoEC Test results can be analyzed and graphically viewed in the GL's AutoECTest Viewer (Automatic Echo Canceller Test Viewer) application AutoECTestViewer can view the results from either T1 or E1 version of AutoECTest.
AutoECTest Test software has been designed to automatically test EC (echo cancellers) compliance with ITU-T G.168 Specification, G.168 (01/2007), G.168 (08/2004), G.168 (06/2002), and G.168 (04/2000)
There are three (3) core functions of AutoEC Test applications:
- Test EC for G.168 compliance
- Analyze the result files, formally named as Sout PCM data files, and save the results into a MAT file contains the complex binary
data format
- Present the test results in graphical, CSV, or text formats
Core functionalities 2 & 3 distinguish AutoECTest Viewer from AutoEC Test application.
The MAT file contains a complex data structure, which has one record for each test case. For each test case, the corresponding
record contains the test parameters (such as Test name, CSS level, ERL, delay, filter type, and so on), analysis results (such as
pass/fail flag, residual values and locations, G.168 requirements, and so on), and pointers to the Sout file names and locations.
If the Sout files are available and stored in the location specified, then, the offline analysis function is activated. In addition,
the graphical presentation of the AutoECTest results is repeatable.
If the Sout files are not available, then, AutoEC Viewer can only generate the AutoECTest result reports in both text and CSV
formats. The screen below depicts the passed test cases:
Features
- Supports *.csv and *.xls format files for AutoEC Test results analysis
- Results can be saved in *.txt format files
- Graphical view of the Sout PCM data file (if it is available), including the G.168 requirement masks
- Offline analyze of the Sout PCM data files (if available)
Analysis of Test Cases using AutoECTest Viewer
For offline analysis and graphical presentation of the AutoECTest application, the raw Sout PCM data files should be necessarily
stored in the location mentioned. Users may create this directory manually, and copy the raw Sout PCM data files to this directory.
'Failed' is defined as that the Sout results fail to meet one or more G.168(01/2007), G.168 (08/2004), G.168 (06/2002), and G.168 (04/2000) requirements. The screen depicts the failed test cases.
For example, the G.168(01/2007), G.168 (08/2004), G.168 (06/2002), and G.168 (04/2000) requirements for Test 2B Part A include the convergence requirements, the residual requirement and the peak value requirement.
The five G.168 requirements for Test 2B Part A are:
- The first 50 ms convergence requirement
- Convergence requirement from 50 ms to 1 sec
- Convergence requirement from 1 sec to 10 secs
- Residual requirement from 10 secs to 3 mins
- Peak value requirement from 10 secs to 3 mins
Every requirement is met for a "Pass" test case, otherwise, test cases are declared as "Failed".
AutoECTest Viewer Results
Graphical Presentation
The graphical presentation of the Sout file for any test case can be viewed with the Sout file located in the
specified "Raw PCM Sout File Location" directory.
Offline analysis of AutoECTest results is performed on the Sout PCM data. Normally, the AutoECTest result
MAT file contains the final results. "Analysis All" option allows the users to re-analyze all Sout files.
Analyzing Sout files are computational extensive as Sout files are large. For example, Test 2A or Test 2B, the
test duration is 3 minutes, which is 180 seconds by 8000 samples/second. It is of 1440000 samples, and is
calculated using double precision so the size of the data files remains around 2.88Mbytes.
After the offline analysis (individual test case analysis or all test case analysis), the result data structure values
will be changed accordingly. Generally, the new values should be the same to the old values, but marginally
differences may exist.
Save Results
"Overall result summary" option displays the complete summary of the EC Test results.
The AutoECTest results can be exported as a *.csv file. The CSV file can be imported into Excel for further processing.
The AutoECTest results can also be saved as a *.txt file. The text file screen depicts the condensed information of the
AutoECTest results. Further a simple script can be written to parse and process those data.
Screen shot of AutoECTest results in a text file
For Voice Enhancement and Voice Quality Testing
- Solution 1. Voice Enhancement and Voice Quality Testing
- This software is designed to test the functionality of the voice enhancement devices per G.160, including
- Voice quality tests per P800/P861/P862
- Noise reduction tests
- Automatic level control tests
- Noise compensation tests
- Test results are presented in easy to hear "audible" and easy to understand graphical formats
- Required software xx067 and includes xx019 Tx/Rx File Utility or xx600, xx610, and xx630 WCS components
- Also required VQT001 and VQT003. Consult with GL for design choices
- Additional recommended software xx020, xx062, and xx066
- Solution 2. Voice Enhancement Device Test Per G.160 and G.169
- This software is designed to test the functionality of the voice enhancement devices per G.160 and G.169, including
- Signaling tones tests,
- Noise reduction signal level tests,
- Noise compensation tests,
- ALC (automatic level control) tests,
- Receive path VIT (voice improvement test) tests,
- Send path EVI (enhanced voice intelligibility) tests
- Required software xx069
- Also required xx019 Tx/Rx File Utility or xx600, xx610, and xx630 WCS components,
- Also required VQT001 and VQT003,
- Consult with GL for design choices. Additional recommended software xx020, xx062, and xx066
Buyer's Guide
Please Note:
The XX in the Item No. refers to the hardware platform, listed at the bottom of the Buyer's Guide, which the software will be running on. Therefore, XX can either be HDT, HDE, or UTE depending upon the hardware.
Back to Echo Canceller Testing Solutions Main Page
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![Screen Shot of Setting EC test parameters per G.168 - version 01/2007](javascript:myOpen("images/autoectest_image13.gif")){kind=link}
![Echo Canceller Test Result Analysis Summary](javascript:myOpen("images/SA_echocancellertesting3.gif")){kind=link}
![Selection of Individual Test Case Analysis Results](javascript:myOpen("images/SA_echocancellertesting4.gif")){kind=link}
![Graph of Overall G.168 Requirements and Test 2B Results](javascript:myOpen("images/SA_echocancellertesting5.gif")){kind=link}
![Detailed Graph of Individual Test Case which Passed Test 2B](javascript:myOpen("images/SA_echocancellertesting6.gif")){kind=link}
![Detailed Graph of Individual Test Case which Failed Test 2B](javascript:myOpen("images/SA_echocancellertesting7.gif")){kind=link}
![Zoomed in Graph Showing Why Test Case Failed](javascript:myOpen("images/SA_echocancellertesting8.gif")){kind=link}
![Test 2B Convergence Time Requirements and Test Results](javascript:myOpen("images/SA_echocancellertesting9.gif")){kind=link}
![Automated Analog Echo Canceller Testing](javascript:myOpen("images/SA_echocancellertesting10.gif")){kind=link}
![Echo Canceller RS 232 Control Setup](javascript:myOpen("images/SA_echocancellertesting11.gif")){kind=link}
![Initialize GL Card Setup](javascript:myOpen("images/SA_echocancellertesting12.gif")){kind=link}
![VQT Test Scenarios](javascript:myOpen("images/SA_echocancellertesting13.gif")){kind=link}
