A theoretical description for the multiple-signal operation of a TWT

A multiple-large-signal theory for traveling-wave tubes (TWT's) is developed. The equations associated with the growth of the signal waves along the length of the tube are integrated by means of digital computation methods. The assumptions made during the theoretical formulation are more restrictive than those made by El-Shandwily in his multiple-large-signal theory, however, by restricting the generality of the theory judiciously, the computer time normally required to make calculations of this type is substantially reduced, Calculations have been presented for only a few special cases. Computed results are presented here for the growth of up to 12 input signals and some of the more imporant intermodulation products. Agreement between theoretical predictions and experimental results are shown for the case of two input signals. In addition some important empirical relations are developed which can be used to approximately predict the large signal performance of a TWT and to further reduce the computer time.