We introduce the SINRk model, which is a practical version of the SINR model. In the SINRk model, in order to determine whether s’s signal is received at c, where s is a sender and c is a receiver, one only considers the k most significant senders w.r.t. to c (other than s). Assuming uniform power, these are the k closest senders to c (other than s). Under this model, we consider the well-studied scheduling problem: Given a set L of sender-receiver requests, find a partition of L into a minimum number of subsets (rounds), such that in each subset all requests can be satisfied simultaneously. We present an O(1)- approximation algorithm for the scheduling problem (under the SINRk model). For comparison, the best known approximation ratio under the SINR model is O(log n). We also present an O(1)-approximation algorithm for the maximum capacity problem (i.e., for the single round problem), obtaining a constant of approximation which is considerably better than those obtained under the SINR model. Finally, for the special case where k = 1, we present a PTAS for the maximum capacity problem. Our algorithms are based on geometric analysis of the SINRk model.