Handover Test Systems are used to simulate the process of handover of signals from one base station to the next in cellular or WLAN networks within the controlled space of laboratories. These devices fade/attenuate the strength of RF signals using numerous variable attenuators which act as various RF paths (channels) that are available between the base station/access point to the mobile device. This helps network engineers to predict the performance of the systems in real-world situations and make necessary updates to the network design.
The eDHT digitizes the RF paths to incorporate a variety of tight FIR filters (17 filters ranging in bandwidth from 1.25MHz to 100MHz). The eDHT cellular downlink architecture is an extensive RF chain of filters, attenuators, gain blocks, mixers, ADCs/DACs and supports tuning to any frequency in the three supported cellular bands (600MHz-960MHz, 1447MHz-2690MHz and 3.3GHz to 6GHz). The tight digital filtering cannot be achieved in the analog domain, and it allows the end user to ensure their DUT only sees the desired downlink RF signal.
Our system allows testing in real-world conditions using antennas and “live off the air” environments. For example, the carrier of interest could have adjacent carriers 40 dB higher, that the DUT would not be exposed to, which is superior to the typical passive box that simply attenuates the entire composite signal. eDHT allows over-the-air testing with antennas vs a cable-based test. Control of the eDHT can be via the GUI or SCPI commands. The GUI supports CSV scripts to automate multi-day test scenarios.
1.25MHz Digital Filter Sweep
100MHz Digital Filter Sweep