非Kolmogorov大气湍流对径向部分相干阵列光束瑞利区间和湍流距离的影响  

Influence of Non-Kolmogorov Turbulence on the Rayleigh Range and Turbulence Distance of the Radial Partially Coherent Array Beams

作　　者：柯熙政[1,2] 张雅[1] 陈炜 

机构地区：[1]西安理工大学自动化与信息工程学院,西安710048 [2]江苏海虹电子有限公司,江苏扬州225108

出　　处：《光子学报》2016年第11期17-24,共8页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.61377080;60977054)资助~~

摘　　要：基于广义的Huygens-Fresnel原理和非Kolmogorov谱模型,推导了无线光通信系统中径向分布部分相干高斯-谢尔模型阵列光束在非Kolmogorov大气湍流中传输时瑞利区间z_R和湍流距离z_T的解析表达式,对瑞利区间和湍流距离随湍流参量和光束参量的变化情况进行了数值分析.结果表明:不论是相干还是非相干合成,径向分布部分相干高斯-谢尔模型阵列光束的z_R和z_T均随湍流广义指数α的增大非单调变化,当α=3.11时,z_R和z_T取最小值,此时阵列光束扩展最大;相干合成比非相干合成的光束扩展要小,但其受湍流的影响更大;对于相干合成而言,径向分布半径r0越大,合成光束的z_R和z_T就越大,而非相干合成的z_R和z_T不受r0的影响;不论是相干还是非相干合成,阵列子光束数目对合成光束的z_R和z_T没有影响;当光束相干参量β足够小或波长λ足够大时,大气湍流对阵列光束z_R的影响可以忽略.Based on the generalized Huygens-Fresnel principle and the non-Kolmogorov spectral model, the expressions for the Rayleigh range zRand the turbulence distance zTof radial partially coherent Gaussian-Schell model array beams of the free space optics system propagating through non- Kolmogorov turbulence were derived. And the expressions were used to analyze numerically the changes of the Rayleigh range and the turbulence distance with turbulence parameters and beams parameters. The results show that for both coherent and incoherent combinations, the dependence of zRand zTof the radial partially coherent Gaussian-Schell model array beams on generalized parameter α is not monotonic. When α=3.11, zRand zTreach their minima, and this means that the beams spreading is largest. For the coherent combination of beams spreading is smaller than that for the coherent combination, but it is larger affected by turbulence; For coherent combinations, the larger the radial distribution radius r0, the larger the Rayleigh range zRand turbulence distance zTof the combined beam, but incoherent combinations is not affected; for both coherent and incoherent combinations, the number of sub-beams has no influence on the Rayleigh range and the turbulent distance of the combined beam; When beams coherent parameter β is small enough and wavelength λ is large enough, the influence of turbulence on zRcan be ignored. © 2016, Science Press. All right reserved.

关 键 词：无线光通信 径向部分相干阵列光束 非Kolmogorov湍流 相干和非相干合成 瑞利区间 湍流 距离 

分 类 号：TN929.12[电子电信—通信与信息系统]