There are some commercially made body antennas that hang on your body like armor and they work very well over the 30 to 512MHz range but cost a fortune. Lots of engineering in those.
However, there is a POS body worn antenna thought up by a so called military commo guy that is a length of RG-58 coax with the braid removed from about 3/4 of its length and shorted at the far end. Then its woven through a pack or vest in a zig-zag pattern that is not conducive to good RF radiation. This thing is not an antenna, its a cluster fuk thunk up by an idiot who has no clue what an antenna is or how it works.
The "inventor" claims its a "full wave" antenna and he obviously has no clue what that is. It might be a full wavelength at some frequency but not over the 30 to 512MHz range of the MBITR for which is was "invented", or thunk up for.
The antennas supplied with the MBITR have broad band matching circuits that provide a reasonable match across the entire operating range of the radio, where the cluster fuk antenna is just a length of wire woven through a pack or vest and provides a horrific match on most frequencies the MBITR operates on. What a terrible thing to do to a nice radio like the MBITR.
I've tested the TCI style remote mount and when placed high on the body or pack or vest with the stock 1m blade antenna and used with a dangling counterpoise wire it provides quite a bit of gain over the same antenna attached directly to the radio. I have a gain plot over 30 to 512MHZ for both configurations somewhere around here and will post if I can find it.
I have ran pretty much every antenna on the planet at one time or another for my kit. I have spent more money on combo crap than any other kind of kit. I am not a huge fan of mast antennas nor the blade antennas both of the seem to hang on very thing. Blade antennas want to unfold at un opportune times and hit you in the face. I also don't like running my radio on my team radio on my back. most teams hop freaks, casevac freaks are or different freaks than you are on, you support is on another freq, change power settings to minimize signature or raise it to get further out act. So my radio stays on my front. My preferred antenna is a body antenna. I am not sure on the specifics of them or if you can buy them. mine was made buy a 18E buddy of mine. i just wrap it around my neck and tuck it in my shirt very small and non-obstructive. works great. but that is just my pinion