  Telecommunication service providers have to guarantee acceptable speech
quality during a phone call to avoid a negative impact on the users' quality of
experience. Currently, there are different speech quality assessment methods.
ITU-T Recommendation G.107 describes the E-model algorithm, which is a
computational model developed for network planning purposes focused on
narrowband (NB) networks. Later, ITU-T Recommendations G.107.1 and G.107.2 were
developed for wideband (WB) and fullband (FB) networks. These algorithms use
different impairment factors, each one related to different speech
communication steps. However, the NB, WB, and FB E-model algorithms do not
consider wireless techniques used in these networks, such as
Multiple-Input-Multiple-Output (MIMO) systems, which are used to improve the
communication system robustness in the presence of different types of wireless
channel degradation. In this context, the main objective of this study is to
propose a general methodology to incorporate wireless network parameters into
the NB and WB E-model algorithms. To accomplish this goal, MIMO and wireless
channel parameters are incorporated into the E-model algorithms, specifically
into the $I_{e,eff}$ and $I_{e,eff,WB}$ impairment factors. For performance
validation, subjective tests were carried out, and the proposed methodology
reached a Pearson correlation coefficient (PCC) and a root mean square error
(RMSE) of $0.9732$ and $0.2351$, respectively. It is noteworthy that our
proposed methodology does not affect the rest of the E-model input parameters,
and it intends to be useful for wireless network planning in speech
communication services.
