Calibration of the EDGES High-Band Receiver to Observe the Global 21-cm
  Signature from the Epoch of Reionization
  The EDGES High-Band experiment aims to detect the sky-average brightness
temperature of the $21$-cm signal from the Epoch of Reionization (EoR) in the
redshift range $14.8 \gtrsim z \gtrsim 6.5$. To probe this redshifted signal,
EDGES High-Band conducts single-antenna measurements in the frequency range
$90-190$ MHz from the Murchison Radio-astronomy Observatory in Western
Australia. In this paper, we describe the current strategy for calibration of
the EDGES High-Band receiver and report calibration results for the instrument
used in the $2015-2016$ observational campaign. We propagate uncertainties in
the receiver calibration measurements to the antenna temperature using a Monte
Carlo approach. We define a performance objective of $1$~mK residual RMS after
modeling foreground subtraction from a fiducial temperature spectrum using a
five-term polynomial. Most of the calibration uncertainties yield residuals of
$1$~mK or less at $95\%$ confidence. However, current uncertainties in the
antenna and receiver reflection coefficients can lead to residuals of up to
$20$ mK even in low-foreground sky regions. These dominant residuals could be
reduced by 1) improving the accuracy in reflection measurements, especially
their phase 2) improving the impedance match at the antenna-receiver interface,
and 3) decreasing the changes with frequency of the antenna reflection phase.
