Arbitrary Waveform Generation of Enhanced High-Order Harmonics Based on Injection Locking

In this paper, an arbitrary waveform generation scheme of enhanced high-order harmonics based on injection locking technology is proposed. In this scheme, a series of higher and even order harmonic is enlarged and improved by injection locking technology. The high-order rectangular and triangular waves can be obtained by time domain superimposing the high-order harmonics and the first and third harmonics generated by nonlinear modulation. Also, a high-order sawtooth wave and reversed sawtooth wave can be obtained by time domain synthesizing the even-order harmonics of injection locking enhancing and the first and third harmonics generated by nonlinear modulation. In the experiments, a fifth-order triangular wave, a fifth-order rectangular wave, a third order sawtooth wave, and a third-order reversed sawtooth wave with frequency of 5 GHz were successfully generated. Hence, the theoretical and experimental results show that compared to that of the same third-order waveform that simultaneous generating, root mean square error of the fifth-order triangular wave and the rectangular wave increased by 10%-37%. Moreover, it is found that the higher-order approximation waveform can be obtained by increasing the number of injection locking branches.