  Non-orthogonal multiple access (NOMA) scheme enables serving users with the
same resource block i.e. frequency or time by multiplexing the signal of the
users. Intelligent reflecting surfaces (IRS) or reconfigurable intelligent
surfaces (RIS) is a potential approach for increasing transmission efficiency
by modifying signal propagation by tweaking typically passive reflective
components. IRS reconfigures the wireless network in this manner to improve
system performance. The research considered an IRS-assisted downlink NOMA
system. This work modified the reference model by adopting an IRS-specific
frequency-distance-dependent path loss model for IRS-NOMA downlink received
power and signal-to-interference plus noise ratio (SINR) measurement instead of
a typical or conventional distance-dependant path loss model. The incorporation
of an IRS-specific path loss model provides a more convenient and better
measurement compared to the conventional path loss model. Furthermore, this
work figures out an improvement scope in the reference model.
