ATLAS Level-1 Endcap Muon Trigger for Run-3

The LHC is expected to increase its center-of-mass energy to 14 GeV and an instantaneous luminosity to $2.4×10^{34} cm^{-2}s^{-1}$ for Run 3 scheduled from 2021 to 2023. In order to cope with the high event rate, an upgrade of the ATLAS trigger system is required. The Level-1 Endcap Muon trigger system identifies muons with high transverse momentum by combining data from a fast muon trigger detector, TGC. In the ongoing Phase-I upgrade, new detectors called the New-Small-Wheel (NSW) and RPC-BIS78, will be installed in the inner station region for the endcap muon trigger. Finer track information from the NSW and RPC-BIS78 can be used as part of the muon trigger logic to enhance performance significantly. In order to handle data from both TGC and NSW, some new electronics have been developed, including the trigger processor board known as Sector Logic (SL). The SL board has a modern FPGA and huge resource of the FPGA make it possible to implement new trigger algorithms. As a new trigger algorithm, charge identification algorithm has been developed and the accuracy is estimated by simulation. Also, algorithm with NSW has been developed to reject the fake trggers and improve the transverse momentum(pT) resolution. It was tested and the trigger rate was estimated by real data in Run-2