Analysis and experiments of self-injection magnetron

Magnetrons are widely used in microwave-based industrial applications, which are rapidly developing. However, the coupling between their output frequency and power as well as their wideband spectra restricts their further application. In this work, the output frequency and power of a magnetron are decoupled by self-injection. Moreover, the spectral bandwidth is narrowed, and the phase noise is reduced for most loop phase values. In order to predict the frequency variation with loop phase and injection ratio, a theoretical model based on a circuit equivalent to the magnetron is developed. Furthermore,the developed model also shows that the self-injection magnetron is stabler than the free-running magnetron and that the magnetron's phase noise can be reduced significantly for most loop phase values. Experimental results confirm the conclusions obtained using the proposed model.     

微波加热中物料实时温度测量无线传感器及其网络

微波作为新型的清洁能源在工业生产中得到广泛应用.然而,微波选择性加热导致的加热不均匀和微波场中温度难以准确实时测量的问题限制了微波工业设备的高效设计与应用.针对以上问题,本文设计了一种基于无线传感器网络和单片机技术的微波加热温度测量系统,该系统以STM32作为微控制器、CC1101作为无线收发器组成星型无线传感器网络,...     

Modeling and experimental studies of a side band power re-injection locked magnetron

A side band power re-injection locked(SBPRIL) magnetron is presented in this paper. A tuning stub is placed between the external injection locked(EIL) magnetron and the circulator. Side band power of the EIL magnetron is reflected back to the magnetron. The reflected side band power is reused and pulled back to the central frequency. A phase-locking model is developed from circuit theory to explain the process of reuse of side band power in SBPRIL magnetron. Theoretical analysis proves that the side band power is pulled back to the central frequency of the SBPRIL magnetron, then the amplitude of the RF voltage increases and the phase noise performance is improved. Particle-in-cell(PIC) simulation of a 10-vane continuous wave(CW) magnetron model is presented. Computer simulation predicts that the frequency spectrum's peak of the SBPRIL magnetron has an increase of 3.25 d B compared with the free running magnetron. The phase noise performance at the side band offset reduces 12.05 d B for the SBPRIL magnetron. Besides, the SBPRIL magnetron experiment is presented. Experimental results show that the spectrum peak rises by 14.29% for SBPRIL magnetron compared with the free running magnetron. The phase noise reduces more than 25 d B at 45-k Hz offset compared with the free running magnetron.