Am antenna system bandwidth versus harmonic distortion

We have found that the far-field harmonic distortion is minimized when the total harmonic distortion (THD) at the final stage of the transmitter is minimized (when sideband symmetry is approached), and that it is not necessary to get especially close to symmetry to obtain excellent distortfon figures. More importantly, we have found that an improvement in far-field distortion may be accompanied by a considerable decrease in the far-field modulation index at all levels of modulation (for a single tone). We have also been reminded that a single Smith chart is not an exact model for the behavior of the sideband pair in a lumped parameter system, and that an iteration technique can overcome this problem. It has been pointed out that sideband symmetry is not a panacea for real transmitters; thus an attempt to improve the system bandwidth should also be made. Finally, we have seen that vanishing distortion, perhaps a decreased workload for the transmitter, and loudness can all be obtained by following the methods outlined in this paper.