%0 Journal Article %T The Littlewood--Paley--Rubio de Francia property of a Banach space for the case of equal intervals %A T. P. Hyt£¿nen %A J. L. Torrea %A D. V. Yakubovich %J Mathematics %D 2008 %I arXiv %X Let $X$ be a Banach space. It is proved that an analogue of the Rubio de Francia square function estimate for partial sums of the Fourier series of $X$-valued functions holds true for all disjoint collections of subintervals of the set of integers of equal length and for all exponents $p$ greater or equal than 2 if and only if the space $X$ is a UMD space of type 2. The same criterion is obtained for the case of subintervals of the real line and Fourier integrals instead of Fourier series. %U http://arxiv.org/abs/0807.2981v1