Opportunistic CoMP for 5G massive MIMO Multilayer Networks

In the FP7 project METIS we investigate suitable combinations of massive MIMO, joint transmission coordinated multipoint and small cells for future 5G systems. Challenging is a tight integration over small and macro layers. Straight forward is to ensure orthogonality between small and macro cell layers by allocation to different RF frequency bands like e.g. 2.6 and 3.5GHz respectively. Here within the macro layer frequency band an opportunistic tight cooperation between macro and small cell radio stations is being proposed. This requires dual band small cell radio stations operating in a traditional local area frequency band like 3.5GHz for data off loading and simultaneously - and on a need basis - at e.g. 2.6GHz as performance booster for macro UEs. First high level evaluations indicate significant spectral efficiency, capacity and coverage gains for macro cell users benefiting from higher Rx power and rank enhancement.