Table 5.

Evaluation and observation of usage of various existing models for millimeter wave propagation.

Ref	Frequency (GHz)	Environment	Model	Observation
[29]	28 and 73	Indoor office	CI and FI	Simple CI models can be used in indoor wireless channels with the correctness even when using one or two functions that has a connection with the transmitted power.
[40]	28, 38 and 73	Indoor and outdoor	CI	It only provides data for future research.
[41]	73.5	Urban micro and macro cellular	CI and ABG	Simulation shows the accuracy of the CI model to be better than the ABG model as it offers a more stable and acceptable performance with greater level of accuracy.
[42]	2 to 73	Urban microcell and macro cell	CI, CIX and ABG	CI and CIF models show a better goodness of fit and more stable behavior of the components unlike the ABG. Inferring that CI is good for outdoor use.
[43]	1 to 100	Indoor office and shopping mall	3GPP	There is more dependency on the value of the frequency in the indoor environments as compared to the outdoor environments.
[49]	10, 20, and 26	Indoor and outdoor	KED model	It shows that the KED model fits accurately with the indoor environment as well as rounded corners in outdoor scenarios.
[51]	40	Indoor	CI and FI	Analysis of the CI and FI models shows that they have similar values for the PLE and slop line.