Bluetest expanded their unique 5G offering for the RTS65 over-the-air (OTA) test system with a compact antenna test range (CATR) option addressing the 5G community’s need for directive measurements in the FR2 (mmWave) range. This original solution enables directional measurements while still supporting multipath isotropic measurements in both the FR1 (sub-6 GHz) and FR2 (mmWave) ranges. Bluetest has thereby created an exclusive combination of a reverberation chamber and a CATR in one system, creating an indispensable tool for the R&D of 5G devices.

With the introduction of higher frequency bands (FR2) in 5G also comes a need for device antennas with directivity, and beam steering, to improve coverage of the cell sites. Antenna gain and antenna pattern are typically not possible to measure in a regular reverberation chamber. Instead a CATR is preferred for these types of measurements. At the same time, the need for isotropic multipath measurements on lower frequency bands remains and can add valuable device information as well as reduce measurement time in the FR2 bands. 

John Kvarnstrand, method development manager at Bluetest explained,"We are excited to show our new solutions for 5G testing. We really have an outside-the-box thinking in order to create an inside-the-box solution to test everything from 2G to 5G FR1 and FR2 in one system. Our team pushed the cutting-edge of both reverberation chambers and CATR reflector technologies to make this possible. The RTS65 now measures mmWave antenna patterns and carrier aggregation MIMO throughput at the same time in the same system. This enables a comprehensive evaluation of UEs that is very close to how the user equipment work in the field."

A carefully designed dual reflector system made it possible to realize a very compact CATR installation with precision management of the RF radiation minimizing RF spillover to the surrounding reverberation chamber environment. The other essential component of the CATR solution is Bluetest’s unique and patented solution for frequency selective absorbers. This absorber design allows us to maintain a low absorption isotropic multipath environment in FR1 while providing sufficient attenuation of disturbing reflections in FR2 resulting in accurate antenna pattern, EIRP and EIS measurement. 

The proven ability of the Bluetest RTS65 to simultaneously support several MIMO-carriers in multiple frequency bands is maintained and becomes even more significant with 5G and dual connectivity. EN-DC combines the control plane on LTE in FR1 for reliability and user plane on 5G in FR1 or FR2 for bandwidth and higher data rates. Data throughput measurements aggregating the capacity on multiple 4G and 5G MIMO-carriers in FR1 and FR2 are still easily executed and provide valuable insight on the device performance in life-like operating conditions.