Most of the analyses of direct sequence-code division multiple access (DS-CDMA) protocol for centralized packet radio networks are based on the assumption that each system user has a unique spread spectrum code and there is a receiver for each user at the central station. For a system with a very large number of users, this implies a very complex central station. In this paper, we will develop a more efficient DS-CDMA protocol for centralized packet radio networks, which reduces the central station complexity in terms of the required number of receivers, while maintaining the channel throughput at an acceptable level. To reduce the central station complexity, we group all system users into cells and assume that all users in a given cell use the same spread spectrum code. It is found that the central station complexity reduction can be obtained at the price of throughput reduction. However, with an appropriate choice of system parameters, the throughput reduction can be made insignificant compared to the reduction achieved with the required number of receivers.