Nokia Antenna Test Labs

When choosing a new phone, we rarely pay attention to reception quality, showing greater interest in the screen size, multimedia capabilities of the phone, and the battery - simply because we are used to good signal reception and de facto expect that there will be no problems with it. But sometimes troubles with the antenna do happen - many of you probably remember about the “antenna-gate”.


Source: npl.co.uk

To avoid such problems, each manufacturer of mobile phones conducts rigorous testing of antennas in manufactured devices. Of course, initially the antennas are designed along with other parts of the phone, and in the laboratory for testing the device already ends up in its finished form. And, thanks to painstaking and complicated preliminary calculations when designing the antenna, guaranteeing normal signal reception, the final testing may seem like a formality, without passing it, the device will never enter the market.

Occurrence of a problem

For understanding, the first mobile phones had no problems with signal reception quality, because they used external antennas. In 1999, we launched the Nokia 3210, the first phone with a built-in antenna, and from that moment the story began with a thorough testing of the antennas. Since then, a lot of time has passed, and in all phones the antennas began to be hidden inside the case. Moreover, other radio receiving modules appeared in mobile devices - GPS, Bluetooth, Wi-Fi, NFC - all of them are placed very compactly, and their work, as never before, depends on many factors, including the position of the phone in your hand.

Anechoic chambers

To test the performance of the antenna, so-called anechoic chambers are used - expensive rooms with walls with rubber spikes (the cost per square meter is more than 120 thousand rubles). In such cameras there is no echo and any interference or random signals are excluded. It is impossible to create a universal anechoic chamber suitable for all tests, therefore there are several types of them, ranging in size from huge hangars to standard rooms. All these cameras use unique high-tech equipment to simulate cell towers, WiFi networks and Bluetooth devices. To simulate the reception of all these signals in different positions, devices in anechoic chambers are tested on both static and rotating platforms.



From the story with the “Antennate,” everyone must have learned a lesson that the signal level depends on how we hold the phone in our hands. To test such situations, Nokia laboratories use models of human hands that repeat the various ways of holding the phone in the hands of users. There are many such hand models to test phones of all kinds of sizes and form factors. In addition to the models of human hands, mannequins of the human head, which completely repeat the structure of the skull and the conductivity of certain tissues, are also used to test the effectiveness of the antenna.

The results of all these tests are averaged to derive the total radiation power and isotropic sensitivity — these figures reflect the criteria for normal (or abnormal) operation of the device. Our experts spend more than 150 hours to fully check each device that is manufactured - all in order to ensure that device buyers are satisfied with the signal quality of their new phone. By the way, among all tested Nokia phones, the new models, starting with Nokia N9 and ending with Nokia Lumia 900 , show better results.