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The next generation broadband access networks must provide high speed bidirectional data channels and support more concurrent subscribers than ever before. While mega-bits-per-second data rates have been demonstrated for the downlink channels, progress on uplink has been slow. We propose a hybrid architecture for CDMA uplink that seamlessly integrates short-range radio and WCDMA interfaces in the same network. In our scheme, mobile stations (subscribers) can operate as Relaying Mobile Terminal (RMT) to relay uplink traffic for nearby mobile stations. Our analysis and simulations show that the deployment of RMTs significantly reduces the radio transmissions in the CDMA uplink. Moreover, the scheme results in a much lower out-of-cell interference to the neighboring network cells. The problem of finding the optimum RMT set turns out to be NP-hard. Several heuristics are evaluated in terms of RMT size and out-of-cell interference. In particular, we investigated a novel vertex cover based heuristic algorithm. Our method uses mobile pilot signals and mobile location to estimate a interference function for each node. This function is then used in selecting a maximum matching for the candidate RMT set. Simulation results are somewhat surprising: the simple greedy algorithm has very close performance to that of the optimum algorithm when only the RMT size is concerned. When out-of-cell interference is considered, the proposed algorithm outperforms both greedy and 2-approximation algorithm. [ABSTRACT FROM AUTHOR]