NVIS information:

Image from Theory, Modeling, and Practical Applications By W5JCK Copyright © 2009, by Ceburn Jack Swinden


The link will allow you to build just about any NVIS antenna there is. 
If your EMCOMM team is not deploying this antenna locally you may want to hold an awareness class for the team members. 

https://duvalaresjax.org/field-operations-manual/?fbclid=IwAR0ARjZqld_AVcNHI_TKyusTnTzrSw2dqma4Kue5hy0lQ1Mj4waWvNQF1W8