Real-time implementation of cross-layer optimization. Multi-antenna high speed uplink packet access

We present a multi-antenna real-time implementation of a cross-layer uplink scheduler based on a recently developed framework. We outline the theory behind the stability-optimal scheduler, which achieves the entire stability region of the multiple access channel. We discuss the trade-off between theoretical optimality and real-time operation under real-world constraints, which leads to the development of an efficient fair scheduler. Finally, we evaluate the performance of the fair scheduler in experimental measurements (on state-of-the-art hardware) in a typical office scenario, which shows an increase in spectral efficiency and the possibility to guarantee a certain link quality of service threshold.