Upgraded data readout and transmission electronics for the Resistive Plate Chambers of the ATLAS Muon Trigger System for the High Luminosity LHC

The Muon Spectrometer of the ATLAS detector will be significantly modified during the Phase-II upgrade in order to mantain low-momentum trigger thresholds at an acceptable trigger rate also in the increased particle rates, integrated radiation and pile-up of the High Luminosity LHC runs. The new requirements for trigger rate and latency impose the replacement of the current trigger and readout electronics of the Resistive Plate Chambers (RPCs). New Data Collector and Transmitter (DCT) boards will be installed to collect and digitize the RPC data. This paper presents the new trigger and readout scheme of the RPCs and the results of a test bench developed to evaluate the data transmission between the DCT and its back-end counterpart. The communication test bench has been performed using evaluation boards implementing an emulator of the lpGBT ASIC.