一种用于射频电路优化的腔体可调盖板

Cavity Tunable Cover for the Improving of RF Circuit Performance

用于电磁屏蔽的金属盖板,可能使原本匹配好的射频电路在腔体效应的影响下性能恶化。通过对腔体场分布图的分析,提出了一种腔体可调盖板。结合相关文献,计算出对腔体效应影响最明显的位置,在盖板上安装优化过的调谐螺钉。通过调整调谐螺钉和介质板之间的缝隙,改变腔体效应的影响。对于功率放大电路,可以改变腔体的谐振频率,提高功放的稳定系数。对于环形器电路,可以改善敏感电路的匹配,提高射频性能。微波组件的批量生产过程中,不同批次之间的元器件性能的差异,也可通过可调盖板来进行调整,降低生产过程中的调试工作量,提高产品的可靠性。

Metal shielding covers are used to prevent the radiations and provide immunity to the printed boards. But well-matched RF circuits would be interfered by the cavity effect. Here the cavity model is setup to analyze the cavity effect and the tunable cover is proposed. Calculation and simulations indicate that some locations can significantly suppress the cavity effect. After adding screws,the cavity effect can be modified by tuning the gap between screw and PCB. For the PA circuit,it could adjust the cavity resonant frequency and improve the stable factor. For circulator circuit,it could improve the match between sensitivity components. Tunable cover could also compensate the performance jitter between different batches during the long time production. It would reduce the tuning work load and increase the product reliability during volume production.