I am setting up a Radial basis Neural Network (RBNN). Most applications have used gaussian radial basis function. However I plotted the distribution of my output and noticed it to be bimodal. Will this have an effect?
In case you mean that the input to the NN is multimodal, this should be unproblematic for RBNNs. The idea is that the weighted sum of a high number of RBF kernels can resemble any (multimodal or not) distribution function. Illustratively, this is similar to resembling a unknown distribution function as a sum of e.g. Gaussians in Kernel density estimation (the samples in KDE would correspond to neurons in RBNN, if there was no weighting).