  As experiments in high energy physics aims to measure increasingly rare
processes, the experiments continually strive to increase the expected signal
yields. In the case of the High Luminosity upgrade of the LHC, the luminosity
is raised by increasing the number of simultaneous proton-proton interactions,
so-called pile-up. This increases the expected yields of signal and background
processes alike. The signal is embedded in a large background of processes that
mimic that of signal events. It is therefore imperative for the experiments to
develop new triggering methods to effectively distinguish the interesting
events from the background. We present a comparison of two methods for
filtering detector hits to be used for triggering on particle tracks: one based
on a pattern matching technique using Associative Memory (AM) chips and the
other based on the Hough transform. Their efficiency and hit rejection are
evaluated for proton-proton collisions with varying amounts of pile-up using a
simulation of a generic silicon tracking detector. It is found that, while both
methods are feasible options for an efficient track trigger, the AM based
pattern matching produces a lower number of hit combinations with respect to
the Hough transform whilst keeping more of the true signal hits. We also
present the effect on the two methods when increasing the amount of support
material in the detector and introducing inefficiencies by deactivating
detector modules. The increased support material has negligible effects on the
efficiency for both methods, while dropping 5% (10%) of the available modules
decreases the efficiency to about 95% (87%) for both methods, irrespectively of
the amount of pile-up.
