Higher order frequency multipliers-a solution for MM- and subMM-wave local oscillator signal generation

A frequency quadrupler for 140 GHz and frequency doublers for 183 GHz and 230 GHz have been analyzed both theoretically and experimentally. The generation of a 345-GHz signal using a doubler, tripler, quadrupler, or two cascaded doublers and the generation of a 460-GHz signal using a doubler, quadrupler, or two cascaded doublers have been theoretically compared. It is found that if tube oscillators are available at 170-230 GHz, the best choice for producing 345 or 460 GHz signals is a doubler. This is due to its relative simplicity, which allows a wider operational range in comparison to higher order multipliers. However, if an all-solid-state source is required, a higher order multiplier is often a more reasonable choice.<<ETX>>