There are two ways of using optical camera.I don't see any cameras either. I read somewhere they use other drones in the vicinity for targetting.
It's strange, even a plain optical camera would have been useful and not added much cost or weight. I imagine the Iranians struggled to integrate the electronics or datalink.
The video feed is transmitted through data link to controller. This is the cheap option, but it demands high bandwidth and the drone must fly high due to the curve of the earth if the controller is on ground. This limit the range. I guess Iran doesn't have the means of having controllers airborne although that will solve the problem of range to some extent.
The other way is optical targeting by image comparison and recognition. It is like radar. It will make the drone much more expensive though.
I don't think it is wise for any loiter munitions using datalink (via sat or aircraft) because the size limitation. On-board optical or radar homing is a choice except higher price.