基于移频环路扩频的新型宽带扫频光源

A Novel Broadened Frequency Sweeping Optical Source with Wide Linewidth Based on Optical Recirculating Frequency Shifter

扫频光源(FSOS)在光通信、光传感和光成像等领域得到广泛应用,其扫频宽度和扫频速度直接影响了这些应用的性能。提出了一种明显改善扫频激光光源扫频范围和扫频速度的新方法,在移频环路中引入单边带调制,增强扫频电光调制,产生高阶稳定的光梳,从而在保证相同线性度和窄线宽条件下,利用窄带的扫频电信号获得宽的光扫频范围。利用200 MHz的射频扫频宽度得到约11.44GHz的光扫频宽度,扩频约57倍,由于每次扫频时间相同,扫频速度也提高约57倍。

Frequency sweeping optical source（FSOS）is widely used in optical communications,optical sensing and optical imaging.Sweeping span and sweeping speed of the FSOS is critical to its performance.A new method to broaden the sweeping span and accelerate the sweeping speed of the FSOS is proposed.Single sideband modulation is adopted in a recirculating frequency shifter to enhance the frequency sweeping electric-optic modulation and generate stable high-order optical comb.So a wider optical frequency sweeping span is obtained with narrow-band electrical sweeping signal given the identical linearity and narrow linewidth.An optical frequency sweeping span of 11.44 GHz is obtained by radio frequency sweeping span of 200 MHz,the frequency is broadened approximately by 57 times.Meanwhile,the frequency sweeping speed is improved by 57 times as each sweeping period remains not changed.