[Ozziewolf]

The title basically sums up what I have in mind.

The thermal target would be a deployable that when viewed through a thermal scope would look like a person off in the distance. Up close it could look like anything from a card board cut out in the shape of a person to some sort of small device that projects the heat signature on to a nearby surface.

My other idea is a heat grenade. Little to no damage the heat grenade would create a large heat radius that would obscure any one in or behind it when viewed through thermal scopes. At most when looking through the heat wave with a normal scope you'd see some wavy mirage effect that wouldn't really obscure vision.
Functionally it's a smoke grenade that is only useful at night against thermal scopes.