Over-the-air testing on the rise

The test and measurement industry in the Netherlands is going through a transition. More and more companies are switching to wireless testing, also known as over the air (OTA) . “The great advantage of over the air is that you test the device as it actually functions,” says Matthijs Kronenburg of Accelonix, one of the first companies in the Netherlands to apply OTA test solutions. “This reduces the chance of errors.”

Kronenburg gives the example of testing a new model of mobile phone. "In the test room we place a doll with the phone next to its ear. Then a robot arm turns the doll in all directions, just as it actually does when you make a phone call. By measuring the radiation pattern three-dimensionally, it is possible to determine the direction of the radiation. beam “to be determined very precisely.”

Cost-saving

OTA testing is particularly ideal for products where beamformation is important. “You optimize the beam during testing,” Kronenburg explains. “In the test chamber, you determine the direction of the beams using a prototype. When the object goes into production, the beam pattern of all copies must be identical to that of the prototype. This must then be reproduced very accurately. Another efficient way is to follow a less accurate production process and measure each product separately. During this process, you immediately program the optimal configurations into the product. The latter is often cost-saving for the manufacturer.”

Easily scalable

The first reactions of customers on over the air testing, are positive: “It is a practical way of testing that is easily scalable. You have test rooms of tens of square meters, but there are also 'rooms' the size of a refrigerator. This makes OTA testing attractive for companies of different sizes.”

Robot arm OTA

Kronenburg shows a picture of a typical RF test chamber: a futuristic-looking room with pointed, anechoic material on the walls that absorbs the RF radiation. An antenna is attached to the wall, aimed at a positioner with a robot arm in the middle of the room. The employee sits outside the test room behind a computer and follows the progress of the test via the test software using radio protocols beam-optimization.

Rise of 5G

“Wireless technology is not new. It has been used in the United States for years,” Kronenburg explains. “Dutch test and measurement companies are not yet enthusiastic about wireless test technology. Due to the rise of 5G and other mobile communication methods, and the growing demand from customers, I expect that to change in the short term.”

A keeper

Kronenburg is ready, he says: “OTA offers us the possibility to be flexible with specific aspects that are important to the customer. We can even reuse materials and instrumentation if necessary. This flexibility makes over the air a keeper.”