A cascaded microwave photonic filter based on a lowcoherence infinite-impulse-response filter

• 来源期刊: 光电子快报(英文版)
• 学科: 工学
• 年，卷（期）: 2013,（3）
• 页码范围: 165-168
• 页数: 4页
• 分类号: TN713
• 语种: 中文

摘要

A cascaded filter combining active and passive filters is proposed. The active filter acts as a low-coherence infinite-impulse-response (IIR) filter and achieves a sharp frequency response. The low-coherence IIR filter is realized by employing the cross-gain modulation (XGM) of the amplified spontaneous emission (ASE) spectrum of the semiconductor optical amplifier (SOA). The passive filter is an n-section unbalance Mach-Zehnder (UMZ) structure, which is used to increase free spectral range (FSR) and Q factor further. The low-coherence IIR filter cascaded with one section of UMZ passive filter is experimentally demonstrated, and a Q factor of 1268 is obtained.