Drive Testing / Benchmarking

Overview

Quality benchmark is not the same as field testing as viewed by engineers in network troubleshooting and tuning; it is a comparison of multiple networks with the intention of finding out how they rank performance wise. It is an increasing priority throughout the mobile telecoms industry. Quality parameters are measured from the scribers perspective, but the engineering values also provide information needed to identify and resolve problems that can degrade network quality. Operators want to know their own and their competitors' weaknesses and if prospective customers are really finding better service elsewhere so changes can be made before it is too late.

Benchmarking reports reflect the mobile phone users’ experience and can relate to voice or data services. According to a recent Yankee Group study, the single most important factor affecting subscriber attitude is network reliability. Accordingly, Key Performance Indicators (KPI's) have been identified that gage how the subscriber perceives the network.

Drive tests are part of the quality equation and can assess quality performance data over large area. Indoor and pedestrian areas are equally important to benchmarking studies as customers want to use their mobile phone anywhere and should always be included in a QoS management plan.

There are several other applications - besides benchmarking and trend analysis where drive tests are often deployed. These include network optimization, acceptance testing expansions, and new technology implementation evaluation as well as scan drives for engineering maintenance. Even at the early stage of network construction, drive test is a major way to evaluate network condition.

QoS Measurements

Drive test and Indoor Quality of Services (QoS) parameters are a true representation of what the subscriber experiences in the network. With QVoice results of QoS measurements made on competitors' or own network can viewed in real time during the drive (or indoor) test or in QVP - a comprehensive post-processing and reporting system.

An important advantage of QVoice is that the QoS measurements can be made almost on any air interface technology, simultaneously. For example, the same speech call tests can be made on GSM, WCDMA and give the drop call / failed call rates as well as determining real comparative speech quality. Similarly, mobile data test like FTP, UDP and Email can be made on GSM, GPRS, HSCSD, WCDMA, HSDPA and give invaluable results for each network/technology.

Mobile Speech Call Tests

QVoice allows the user to define the test call parameters, which can be MOC, MTC, MOC/MTC mixed or mobile-mobile. The speech signal direction can be uplink, downlink and half-duplex. Call duration, retry interval, pauses and other criteria can also be pre-programmed.

The most important voice benchmarking KPIs are as follows:

• Service Coverage - percentage of call attempts that fail due to no service
• Retainability - how often are subscribers interrupted by dropped calls
• Voice Quality - a value of voice scores as classified to a vast majority of user (MOS)
• Access Time - delay time before a call starts ringing
• Throughput - the average rate to download or upload a file

Mobile IP-Data Tests

These tests measure the performance o the network with respect to transferring data and messages. There are suite of test protocols available for QVoice systems including the most popular FTP, UDP, SMS/MMS, PING and Email.