A thought or two to consider: ?If you make a small 1-turn loop that is 50% efficient, then half the power you feed into it gets turned into RF that radiates.? If you make a small 2-turn loop and manage to keep the efficiency at 50%, the best it can do is radiate the same.
In order to get a better radiator, either the efficiency must go up (less losses), or the antenna can be made more directional to concentrate some of that energy in a particular direction.? I don't think you can change the directionality of an electrically small loop by using the same basic coil form.? Any electrically small round loop in air has pretty much the same directionality to it.
So the thing you need to concentrate on, is cutting the I*R losses.
Connecting the turns in parallel, rather than series, may help with that.
The different number of turns can affect the impedance seen by whatever drives the antenna, so it might affect your ability to match the antenna and get power into it.
A large loop antenna (i.e., circumference comparable to a half wavelength or more) plays by different rules than a small loop.? In a small loop where the total wire length is short, the current in each turn is the same, so their effects complement one another.? In a large loop, the currents could be out-of-phase between one turn and the next turn, resulting in rather different results (partial cancellation?).
Regards,
Andy
