Methods and apparatus for acquiring diffusion-weighted images. The method comprises selecting a plurality of diffusion gradient vectors, wherein at least two of the plurality of diffusion gradient vectors correspond to different non-zero b-values. The method further comprises determining a gradient strength for each of the plurality of diffusion gradient vectors such that an echo image time (TE) remains constant when gradients corresponding to each of the plurality of diffusion gradient vectors are applied. The method further comprises acquiring the diffusion-weighted images using a gradient encoding scheme including the gradients corresponding to each of the plurality of gradient vectors.