Rohde & Schwarz at Mobile Antenna Systems 2012 in Denver
The list of speakers includes Thorsten Hertel, who has a PhD from the Georgia Institute of Technology and is OTA Product Specialist at Rohde & Schwarz USA. He will discuss the MIMO OTA decomposition approach.
Over-the-air (OTA) testing is an established technique used to measure the wireless system performance of mobile devices in addition to characterizing the antenna subsystem. 3D radiation patterns of transmit power and receive sensitivity are used to determine a figure of merit (FOM) for transmitter and receiver performance, i.e. total radiated power (TRP) and total isotropic sensitivity (TIS), respectively. For LTE, attention is mainly focused on the MIMO receiver chain evaluation. There have been ongoing discussions for quite some time on how OTA testing can be updated to support LTE MIMO. The LTE MIMO OTA decomposition approach determines separate FOMs for the key MIMO receiver chain subsystems. The conducted MIMO test utilizes a fading simulator to introduce dynamic fading and is used to determine a FOM for MIMO receiver performance. The radiated test is performed without the introduction of fading profiles inside the anechoic chamber and is used to determine a FOM for the MIMO receive antenna pair with the device under test in the OLSM transmission scheme. The FOM for the overall MIMO performance of the DUT is a combination of the FOMs from each test (conducted and radiated). Splitting up MIMO wireless system performance testing into two straightforward and cost-effective tests provides more information about the DUT’s performance than a complex single test. The radiated tests take realistic angles of arrival (AoAs) for the MIMO streams into account and provide sufficient control over the AoAs in 3D by defining the origins and the polarizations of the MIMO streams. In addition to providing an antenna-specific FOM, the radiated test can be used to provide a FOM for device performance with the DUT exposed to basic MIMO conditions, since device-level performance metrics are captured by default.
Do you want to learn more? Don’t miss this lecture at Mobile Antenna Systems 2012.
Antenna Systems 2012