Throughput of Low-Power Cellular Systems With Collaborative Base Stations and Relaying

In this correspondence, joint (cooperative) decoding at the base stations combined with collaborative transmission (relaying) is investigated as a means to improve the uplink throughput of current cellular systems over fading channels. Intracell orthogonal medium access control (e.g., TDMA, FDMA, or orthogonal CDMA) and Decode-and-Forward relaying by either a mobile terminal or a fixed relay are assumed. Moreover, the cellular system is modeled according to a simplified framework introduced by Wyner. The per-cell achievable ergodic throughput is calculated for different system configurations and then characterized in the low-power (wideband) regime in terms of minimum energy per bit required for reliable communication and slope of the spectral efficiency. The analysis allows to clearly assess the relative merits of both cooperation among base stations and at the terminal level within the considered model.