Study On The Characteristics Of New Device In The Structure Of Fiber Ring Resonator

With the rapid development of optical communication technology,the optical communication capacity,transmission rate and communication distance of the increasingly high demand.Optical communication filter to solve the problem of optical fiber communication frequency band utilization rate,but also improve the transmission rate and capacity of communication system.The optical filter is a wavelength division multiplexing(DWDM)is one of the key devices in optical signal control in the system,which is the most practical optical fiber ring resonator filter.The optical signal into two signals through the 3dB coupler,respectively along the ring clockwise and counterclockwise transmission,finally in the coupler due to meet between the two phase difference so the interference effect and the output of coherent signals.In the ring cavity in high birefringence fiber taper.Cascade fiber and cone structure M-Z interferometer and other new optical fiber devices,can improve the filtering characteristics of the filter.Pull cone fiber by changing the physical parameters of the optical characteristics of the optical fiber to change,thus resulting in the change of the mode of transmission,part in the core light energy to swiftly died field coupled to the cladding,forming structure instrument within the fiber Mach-Zehnder interferometer.This paper in single-mode fiber drawing two structure is exactly the same thin cone a M-Z interferometer and the structure with multi-channel comb filter properties,can be used in optical fiber communication,can also be used in the field of optical fiber sensor as temperature and humidity,stress and refractive index sensor.1.Theoretical analysis the working principle of optical fiber ring resonator,explore the characteristics of the tapered fiber,tapered fiber classification and production of tapered fiber method.At the same time,we analysis the high birefringence fiber classification and how to select the parameters of high birefringence fiber.2.Based on tapered fiber to produce cascaded thin cone structure of Mach-Zehnder(M-Z)interferometer,analyzing cascade cone structure of different types of interference principle of the interferometer.New structure of M-Z can be used in the sensing field,this paper analyzes the principle on the refractive index sensing.3.The new device is inserted into the fiber ring cavity by the tapered fiber,thehigh birefringence optical fiber and the M-Z interferometer with cascaded thin cone structure,and the characteristics of the new device are analyzed.The fiber ring cavity is positioned into the cone cascaded M-Z interferometer are studied theoretically and experimentally,the new ring resonator filter transmission spectrum by the M-Z interferometer and the ring cavity interference with non coherent superposition and tuning M-Z interferometer to achieve tunable filter.Studies have shown that,filter in60 nm free spectrum(1490nm-1550nm)range can be tuned,stable output waveform,modulation depth greater than 20 dB,the structure optimized fiber loop mirror filter characteristics.