The ultimate test for a developer or quality test engineer is one that perfectly captures the user experience in a controlled, repeatable, and cost-effective way, where devices and systems are guaranteed to work as designed when delivered to the consumer. In wireless product testing, this is a huge challenge. As a user device moves throughout a network, over-the-air, real-world conditions change frequently. In addition, the device may be affected by many factors that seem impossible to replicate.

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“Recreating air” or modeling the effects of typical over-the-air transmission phenomena has long been performed using channel emulation and modeling tools. Now, there’s another option that combines channel modeling with data collected in the field in real-world deployments. It has proven effective in both pre-deployment device and infrastructure performance testing as well as in post-deployment troubleshooting and field problem resoluiton.

Armed with drive test data collected in the field, this field-to-lab test methodology can more accurately recreate additional elements that are important in lab-based network testing and that have never before factored into the testing. These variables include rapid variation of signal strength; the fact that multiple sectors are visible to the user in most real deployments; and the fluctuating speed of the device or the rate of change of air-effect phenomena.  Until now, lab testing typically ignored these parameters.

George Reed is the vice president of marketing and product management atAzimuth Systems Inc. He holds a BSEE from the University of Illinois, an MSEE from Columbia University, and an MBA from Fairleigh Dickinson University. He can be reached at george_reed@azimuthsystems.com.

Combining this important information from drive test logs with an effective channel emulation environment creates a test solution that’s closer than ever to the “real world” for existing 2G, 3G, and emerging 4G radio technologies.

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