本文发展了使用幂次式展开收敛域中含有支点的复变函数的方法.在无穷阶支点下，函数的展开式化为积分的形式，称之为洛朗变换.文章还探讨了部分典型函数的展开结果及其完备性问题，并提出了使用连续复幂次代替实幂的方法.最后，举出一例简释了该方法在信号系统中的实际应用，展望了应用前景.

This paper develops a method of expansions for complex functions in the neighborhood of its branchpoint. Its expansion turns into the form of integral when it comes to infinite-order branch points, which is named after Laurent transform. Attempt is employed to try to get the expansion of several sample functions, with judging the completeness for the expansions. Plus, to use the form of complex-power expansions instead of real-power ones is imagined. One example is employed in signal system to explain its practical application and future prospect at last.