  The novel electron spectrometry method proposed by the PTOLEMY relic neutrino
experiment requires a real-time, non-destructive estimate of the parallel and
transverse momentum splits of tritium $\beta$-decay electrons. The
collaboration has proposed to obtain this estimate using cyclotron-radiation
emission spectroscopy (CRES), in which the kinetic energy of a charged particle
is determined by measuring the relativistic frequency shift of the cyclotron
radiation emitted by the particle in a magnetic field. However, no suitable
approach to extract this information in a non-destructive manner has been
developed to date. In this paper, we characterize the performance of a
configuration that can be feasibly integrated directly into the existing design
for the transverse drift filter proposed by the PTOLEMY collaboration. We study
a geometry incorporating a cavity resonator to enhance a ${\sim}\mathcal{O}(1)
\hspace{1mm}\mathrm{fW}$ cyclotron radiation signal and derive key features of
the expected observed radiation specific to our radio-frequency (RF) tracking
configuration. We estimate the performance of our design using electromagnetic
simulations and propose a general signal reconstruction algorithm capable of
matching an observed signal to electron kinematic parameters. The projected
signal-to-noise ratio (SNR) of this technique suggests that a non-destructive
RF tracking system based on an array of these components as building blocks is
applicable for extracting the kinematic parameters of tritium endpoint
electrons to the precision required for the PTOLEMY experiment.
