In this paper, we explore the problem of processing a novel type of location based queries, named the location based top-k query, which involves both of spatial and non-spatial specifications for data objects in the wireless broadcasting system. We introduce two methods for processing location based top-k queries on the broadcast stream. In the first method, the search algorithm runs on the broadcast aggregate R-tree (aR-tree). However, the aR-tree may deteriorate the search performance, especially in terms of the tuning time. With this problem in mind, we propose a novel index structure, called the bit-vector R-tree (bR-tree), which stores additional bit-vector information to facilitate processing of location based top-k queries. The search algorithm on the broadcast bR-tree is also described. Our simulation experiments demonstrate that the bR-tree method clearly outperforms the aR-tree method in terms of the tuning time, while maintaining similar or better performance in terms of the access time.