Studies On Frequency Shifted And Swept Technique Of Multi-wavelength Fiber Laser

Frequency sweep fiber laser has widely and important application in fibersensing net, biomedicine and optical frequency domain reflection. This paper mainlystudies the multi-wavelength frequency sweep fiber laser which is based on frequencyshift by using IQ modulator, especially aim at optimizing multi-wavelength based onSOA. The research makes the number of output multi-wavelength which powerdifference in1.5dBincrease and make the line width of multi-wavelength outputnarrowing. The research study using IQ modulator realize multi-wavelength entirelyfrequency shift with different frequency RF signal, and measuring the precision offrequency shift. This paper proposes the scheme of multi-wavelength frequencysweep fiber laser and dose predictive analysis. The main content of this paper asfollow:1. The optimizing research of multi-wavelength fiber laser(1) Structuring multi-wavelength fiber laser by employing F-P comb filter with50GHz channel space and fineness of14. Research acquired80multi-wavelengthoutput which power difference in1.5dBwhen the injection current of SOA is250mA. We compare the result with the multi-wavelength output by employing F-Pcomb filter with100GHz channel space and fineness of7.(2) Using un-pumped EDF make the line width of multi-wavelength outputnarrowing and measured the line width after narrowing is485MHz. Employing SMFas the secondary cavity of composite cavity to make the line width ofmulti-wavelength output narrowing and measured the line width after narrowing is1.152GHz.2. Realizing multi-wavelength entirely frequency shift by using IQ modulatormodulating outside cavity(1) Analyzing the theory of using IQ modulator realizing single wavelength laserfrequency shift and proposes the scheme of employing IQ modulator make singlewavelength laser frequency shift.(2) Using IQ modulator makes the single wavelength output of DFB laserfrequency shift, acquire the result of which amount of frequency shift is8GHz,10GHz and12GHz. (3) Proposing the scheme of using IQ modulator modulate outside cavity andmake the multi-wavelength entirely frequency shift. Analyzing the process offrequency shift with10GHz RF modulate signal. Acquire result of multi-wavelengthfrequency shift with4GHz，6GHz,8GHz and12GHz amount of frequency shift.(4) Study using heterodyne method to measure the precision of multi-wavelengthfrequency shift which is realizing by IQ modulator and get the precision is150MHz.3. Study of multi-wavelength frequency sweep fiber laser(1) Studying single wavelength frequency sweep fiber laser based on singlewavelength laser frequency shift by using IQ modulator, then proposing the scheme ofsingle wavelength frequency sweep fiber laser. Acquire the output of singlewavelength frequency sweep with10GHz RF modulate.(2) Designing the multi-wavelength frequency sweep laser based onmulti-wavelength entirely frequency shift and predictive analysis the result.