双曲余弦高斯列阵光束在湍流大气中的光束传输因子

本文推导出了双曲余弦高斯(ChG)列阵光束在湍流大气中的光束传输因子( M ^{2因子)的解析公式,并采用相对 M 2因子研究了湍流对 M 2因子的影响.研究表明,在湍流大气中 M 2因子不再是一个传输不变量,湍流使得 M 2因子增大.非相干合成情况下, M 2因子随着传输距离、光束参数、相对子光束间距和子光束数目的增大而增大.相干合成情况下, M 2因子随光束参数和相对子光束间距的增大呈现振荡上升.相干合成情况下的 M 2因子比 关键词： M2因子)')" href="#">光束传输因子(M2因子) 光束质量 双曲余弦高斯列阵光束 大气湍流}

Beam propagation factor of cosh-Gaussian array beams propagating through atmospheric turbulence

The analytical formula for the beam propagation factor ( M ^{2-factor) of cosh-Gaussian (ChG) array beams propagating through atmospheric turbulence is derived, and the influence of turbulence on the M 2-factor is studied by using the relative M 2-factor. It is shown that the M 2-factor is not a propagation invariant in turbulence, and the turbulence results in an increase of the M 2-factor. For the incoherent combination, the M 2-factor of ChG array beams increases with increasing propagation distance, beam parameter, relative beam separation distance and beam number. For the coherent combination, the M 2-factor of ChG array beams increases with oscillatory behavior as the beam parameter or the relative beam separation distance increases. For the coherent combination the M 2-factor is always smaller than that for the incoherent combination. However, for the incoherent combination the M 2-factor is always less sensitive to turbulence than that for the coherent combination. In particular, the influence of turbulence on the M 2-factor can be reduced by a suitable choice of the relative beam separation distance. With increasing beam number, the M 2-factor becomes more sensitive to turbulence for the coherent combination, while for the incoherent combination the M 2-factor becomes less sensitive to turbulence.}