The development of single‐mode lasers with a high side‐mode suppression ratio (SMSR) is challenging but highly desirable for integrated photonics devices and long‐distance communications due to their high spectral purity and stability. There are various types of optical transceivers: SFP, QSFP, 200GbE, 400GbE, and other network standards. It not only works as an OSA module, but also as SMSR analyzer to provide a cost-effective solution to characterizing DFB lasers and transmitters. The OSA-family product is designed and. SMSR is the ratio of the average optical power of the main mode to the optical power of the most significant side mode under the worst transmission conditions. What Is Side Mode? Under ideal conditions, all signals transmitted by optical modules are optical signals of a specified wavelength. Extremely compact, cost-effective optical spectrum analyzers designed for streamlined testing and. This video demonstrates side mode suppression ratio (SMSR) analysis using an AQ6370E optical spectrum analyzer from Yokogawa Test&Measurement and explains how to adjust the signal span to capture side modes and execute SMSR analysis to detect and locate the closest peaks fr.