MIMO technology, a necessary building block for 4G and evolved wireless technologies including LTE and LTE-Advanced, integrates multiple antennas to maximize device performance. To accurately understand performance as experienced by the user, devices need to be tested in the manner in which they are actually used; over the air. This can only be accomplished by testing the entire device in an active operational state, with the actual interaction of the antennas, RF front ends and baseband processing elements.

Azimuth’s revolutionary Real World Performance Measurement (RPM) solution creates a laboratory-based environment where signals are transmitted physically “over the air” to enable the capture of the effects of device design, including antenna design and placement, in a suite of performance measurements that allows testers to accurately distinguish a good device from a poorly performing device. Azimuth provides support for both SISO and MIMO.

Based on a significant R&D effort, Azimuth’s advanced OTA test methodology combines a mobile isotropic chamber with the ACE MX MIMO channel emulator to create an environment where devices can be reliably tested in the same mode as they are used in real-world conditions.

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Azimuth’s fully automated, end-to-end over-the-air test solution is cost-effective, portable, easy-to-use, enabling users to test SISO/MIMO device performance under a multitude of varying channel conditions – accurately and repeatably.

Advanced features include:

• Automation — As one of the only solutions available to incorporate fully automated, integrated SISO/MIMO OTA device testing, The Azimuth RPM Test Solution provides more productive and repeatable testing with fewer errors. Featuring one-step, automated setup, configuration and calibration, as well as automated test execution, Azimuth’s complete automation features also allow for automation of BS/BSE, UEs and other equipment such as network analyzers. The automation scripts are even reusable across companies and product lines.
• Unparalleled Ease-of-Use — The “ready to test” Azimuth RPM Test Solution incorporates “push button” operation that simply requires a user to place a device in its chamber and then begin the test with little setup. Featuring an intuitive and user-friendly interface, the Azimuth OTA Test Solution allows both novices and experts to work with ease. Additional ease-of-use features include detailed and high-level logging, allowing multiple OEMs to run tests using the same setup as an operator, enabling the submission of results in the same format that can be archived and referred to easily.
• Flexibility — Azimuth is closely involved in the development of Figures of Merit (FOM) for MIMO OTA device test. The Azimuth RPM Test Solution currently includes support for throughput as a FOM, providing more dimensions to compare mobile devices and benchmark performance to create a more holistic view of device performance.
• Future Proof — The Azimuth RPM Test Solution has the ability to support additional FOMs that arise in the future (support for two new FOMs will be released subsequently) and to also add more dimensions of reality, such as using drive test data, so that users will rarely find themselves in a situation where they won’t be able to do something with the Azimuth test setup.

While chambers exist that are fully isotropic, they lack some important degrees of realism, namely the ability to control the delay, Doppler and correlation. Azimuth set out to create a chamber that would create a true 3D isotropic environment in a compact form factor without forsaking technical accuracy. The result of this effort is the Azimuth ACE OTA mobile isotropic chamber (MIC); approximately 1.6m x 0.9m x 1m and small enough to fit through most standard doorways! This provides a portability option that until now has not been possible with over-the-air test solutions, eliminating the logistical challenges that are experienced with using the large anechoic chambers used in some SISO/MIMO OTA test methodologies while providing much more test flexibility.

Furthermore, the addition of the award-winning ACE MX MIMO channel emulator enables testers to create real world channel conditions such as delay, Doppler and correlation, with the flexibility to add other channel effects such as shadow fading, noise,etc., and the creation of precise, repeatable channel conditions. This combination of the high fidelity ACE MX wireless channel emulation platform with a compact mobile isotropic chamber creates a truly advanced, cost-effective and portable OTA test solution that can be used to more accurately test mobile devices over the air.

Azimuth’s RPM Test Solution dramatically shortens the product delivery cycle, while improving product quality and reducing overall product costs by enabling more productive, more flexible and more accurate SISO/MIMO OTA testing prior to field testing/deployment.

Video: An Introduction to RPM