Frequency-Locking Characteristics of Magnetron Locked by Injection Start-Up Technology

This article proposes a novel method for adjusting a magnetron’s output frequency range. Experiments demonstrate that injection start-up technology effectively expands the magnetron’s locking bandwidth, consequently increasing the adjustable range of its output frequency. We begin by deriving the phase difference between the output and injection signals over time within the injection start-up technology. We then compare the locking bandwidths achieved through injection start-up technology and injection locking technology. Numerical analysis, simulations, and experiments further validate our derived results. The findings reveal that the phase locking of magnetrons can be achieved even when Adler’s condition is not met. Additionally, the injection start-up technology allows for a wider locking bandwidth of the magnetron, thus fulfilling specific application requirements. This has the potential to benefit applications requiring precise control of microwave frequencies, such as microwave plasma chemical vapor deposition and microwave power synthesis.