Automated CTM testing platform


Introducing the next generation of network test equipment

The DSPGenie offers a highly flexible platform for all your testing and connectivity requirements

 

Introduction

The DSPGenie CTM tester is a multiple DSP based testing solution offering a highly flexible input / output interface that is controlled entirely from software. The wide range of I/O options allows the DSPGenie to be used in virtually any test environment, and bespoke customisation can be done to tailor the platform for any requirements. The I/O options include:

  • Mobile 2.5 mm TSB 121 compliant

  • 2 -wire analogue

  • Optional 4 –wire analogue

  • Optional VoIP (H.323 / SIP)

  • Optional E1/T1

The Instrument can be completely controlled via a separate client application (communicating via TCP/IP) which allows for remote testing.

 

 

Benefits of the DSPGenie CTM Tester

  • Automated testing using DSP based “soft modems”

  • Minimal user input required

  • Fast / accurate character error rate determination

  • Allows for remote testing

  • Host of other testing suites available

  • Optional textphone testing

  • Eliminates the need for two laptops and Gallaudet/ DSPG testing software

  • Future-proof (software upgradeable)

DSPGenie CTM Tester Description

The Tester eliminates the need for two textphones such as TexLink 9100 MT, two laptops and Gallaudet testing suite required for mobile tests. All that is compressed into the small unit that can fit into the briefcase. The testing process can be fully automated including dialling and call set-up if mobile phone can be controlled via AT commands over RS232 connection.

Mobile CTM testing

  • The CTM modem implementation conforms to 3GPP specification and has been fully verified by Ericsson and other manufacturers.

  • Specially designed “Mobile Baudot” mode allows the DSPGenie to operate with all types of CDMA, TDMA and analogue mobile handsets.

  • Successfully tested with Ericsson, Moto rola, Nokia and Samsung handsets.

  • Can be used on mobile or wire-line networks.

  • The use of V.18 automode in the wire-line connection allows automatic connection to virtually any textphone.

 

Optional PSTN textphone testing

Optionally DSPGenie can be configured for 2-wire operation with two built in DAA modules allowing the Tester to emulate two textphones that can be connected directly to PSTN Network. Dialling, Ringing and other Network call progress signalling are implemented in the Tester.

The Figure below depicts the internal DSP/DAA configuration when 2-wire interfaces are used.

 

 

In the configuration shown above the Tester can be used either as two independent textphones or working in the tandem one sending the reference data file (test sequence) the other receiving it and making calculation of Character Error Rate.

 

The following textphones can be emulated in the DSPGenie CTM tester:

  • V.21

  • V.23

  • Baudot 45.5

  • Baudot 50

  • Bell 103

  • DTMF

  • EDT

  • CTM (PSTN mode)

Tester operation

Using the built-in multi-test mode the DSPGenie can be pre-configured and any number of test may be run sequentially without any user interaction. Figure 4 depicts the main GUI where multiple tests can be queued. For every test, a range of parameters (similar to Figure 5) can be configured.

 

The DSPGenie transmits a modulated reference test sequence via selected interfaces (such as mobile CTM or 2-wire PSTN), and the received characters are demodulated and recorded. The received test sequence is compared with a stored reference and the character error rate (CER) is easily calculated.

Over multiple test runs the DSPGenie is also able to produce an average histogram of the error distribution over time and place. This is a useful tool in diagnosing network performance.

 

Figure 4

 

Figure 5