Department of Electrical Engineering, University of Texas at Dallas, P.O. Box 830688, Richardson, TX 75083, USA.
Sensors (Basel). 2011;11(2):1297-320. doi: 10.3390/s110201297. Epub 2011 Jan 25.
A theoretical study of RF-photonic channelizers using four architectures formed by active integrated filters with tunable gains is presented. The integrated filters are enabled by two- and four-port nano-photonic couplers (NPCs). Lossless and three individual manufacturing cases with high transmission, high reflection, and symmetric couplers are assumed in the work. NPCs behavior is dependent upon the phenomenon of frustrated total internal reflection. Experimentally, photonic channelizers are fabricated in one single semiconductor chip on multi-quantum well epitaxial InP wafers using conventional microelectronics processing techniques. A state space modeling approach is used to derive the transfer functions and analyze the stability of these filters. The ability of adapting using the gains is demonstrated. Our simulation results indicate that the characteristic bandpass and notch filter responses of each structure are the basis of channelizer architectures, and optical gain may be used to adjust filter parameters to obtain a desired frequency magnitude response, especially in the range of 1-5 GHz for the chip with a coupler separation of ∼9 mm. Preliminarily, the measurement of spectral response shows enhancement of quality factor by using higher optical gains. The present compact active filters on an InP-based integrated photonic circuit hold the potential for a variety of channelizer applications. Compared to a pure RF channelizer, photonic channelizers may perform both channelization and down-conversion in an optical domain.
本文提出了一种使用由具有可调增益的有源集成滤波器构成的四种架构的射频光子信道化器的理论研究。集成滤波器由两端口和四端口纳米光子耦合器（NPC）实现。工作中假设无损和三种单独的制造情况具有高传输、高反射和对称耦合器。NPC 的行为取决于完全内反射的受挫现象。在实验中，光子信道化器使用传统微电子加工技术在多量子阱外延 InP 晶圆上的单个半导体芯片上制造。采用状态空间建模方法推导出这些滤波器的传递函数并分析其稳定性。展示了使用增益进行自适应的能力。我们的模拟结果表明，每个结构的特征带通和陷波滤波器响应是信道化器架构的基础，并且光学增益可用于调整滤波器参数以获得所需的频率幅度响应，特别是对于具有约 9mm 耦合器分离的芯片，在 1-5GHz 的范围内。初步的光谱响应测量表明，使用更高的光学增益可以提高品质因数。基于 InP 的集成光子电路上的这种紧凑型有源滤波器具有各种信道化器应用的潜力。与纯射频信道化器相比，光子信道化器可以在光域中同时进行信道化和下变频。
