微波滤波器是无线通信、电子雷达等射频系统中的关键组件之一。硅基微波光子滤波器具有集成化、带宽大、可调谐性强、抗电磁干扰等显著优势, 近年来得到了广泛的关注与研究。文章从微波光子滤波器的工作原理出发, 分别综述了非相干型与相干型两类硅基微波光子滤波器的最新研究进展, 并分析了当前面临的问题与挑战。最后, 对硅基微波光子滤波器的发展现状进行总结, 并对下一步的研究方向进行了展望。

为了解决现有电子式电能表故障检测方法精度偏低、训练速度慢的问题, 提出一种BP-AdaBoost复合神经网络故障预测方法。首先, 在单一BP神经网络的基础上, 利用组合分类器算法AdaBoost对其进行改进, 将多个单一BP神经网络作为弱分类器, 多次迭代训练得到强分类器; 随后, 将该故障预测方法应用于电子式电能表的典型故障——整流桥故障的分类判别中; 利用Simulink搭建电子式电能表仿真模型, 选取故障注入点与观测点, 仿真运行生成的故障数据作为BP-AdaBoost算法的处理对象。仿真结果表明, BP-AdaBoost故障预测方法与单一BP神经网络故障预测方法相比, 能提高预测精度, 显著减小误差, 在实际应用中具有一定可行性。

We demonstrate the long distance transmission of single-carrier frequency division multiple address signals by directly-modulated optically injection-locked vertical-cavity surface-emitting laser. Transmission distance as long as 50 km is achieved at 5 Gb/s (2.5 Gb/s for each user) through data pattern inversion and higher frequency response gain under optical injection locking.

A 60-GHz bidirectional radio-over-fiber (RoF) system using two-carrier-injected distributed feedback (DFB) laser is proposed and demonstrated to realize optical single sideband (SSB) modulation for downlink. An injection-locked Fabry-P′erot laser is also carried out to realize wavelength reuse in uplink. Transmission of 2.5 Gb/s on a 60-GHz carrier for downlink and 622-Mb/s baseband signal for uplink are both successfully demonstrated over 50-km single mode fiber without chromatic dispersion compensation.