Batch verification is a method for verifying digital signatures at once. Batch verification can reduce the computational cost compared to that of verifying each signature one by one, and in particular, batch verification is especially appropriate for systems which are required to verify a large amount of signatures. However, in addition to the above requirement, several types of systems might also require verifying a limited number of digital signatures more and more efficiently in real-time. For this purpose, to improve the efficiency of verifying a limited number of signatures is presumably an important matter. This paper deals with the second requirement and proposes an efficient batch verification technique suitable for verifying a limited number of signatures in real-time. Our method can only be applied to elliptic curve based signatures, and uses one of the two special families of elliptic curves.