Initital Upgrade of the ATLAS Level-1 Calorimeter Trigger

The Level-1 calorimeter trigger (L1Calo) of the ATLAS experiment has been operating well since the start of LHC data taking and played a major role in the Higgs boson discovery. To face the new challenges posed by the upcoming increases of the LHC proton beam energy and luminosity, a series of upgrades is planned for L1Calo. This poster presents the L1Calo upgrade program for the initial upgrade phase in 2013-14. The program includes substantial improvements to the analogue and digital signal processing. Two existing digital algorithm processor subsystems will receive hardware and firmware upgrades to increase the real-time data path bandwidth, allowing topological information to be processed at level-1. An entirely new subsystem, the L1 topological processor, will receive real-time data from both the upgraded L1Calo and L1- muon trigger to perform trigger algorithms based on entire event topologies.