Weather Balloon Wireless Mesh Networking
I understand I am replying to an old post, and that the OP has not been on this site for a while. I am replying to share info which may be useful for others.

It seems that in the RC, FPV, and drone-enthusiasts communities a "cloverleaf" antenna is very popular for life-streaming applications in flight.



Information, design plans, as well as shops, can be found plenty using your favorite search engine.

Some information here and here
(I have no affiliation with any product, commercially or otherwise)

There are various benefits of this antenna.

It is circular polarized, meaning that you do not have to exactly "line up" the receiving antenna as you would with a linear (H or V) polarized antenna. Best is to receive with a circular polarized antenna of course.

The circular polarized signals has the advantage that it has "better penetration properties" compared to linear polarized signals. Thus improves your reception even when objects, trees, buildings (to some extend) are in the signal path. It is probably this, which makes the antenna popular for applications such as posted here.

HTH.