Even if massive multiple-input multiple-output (MIMO) can theoretically bring huge benefits, it incurs substantial hardware complexity and expensive hardware costs. To address these issues while maintaining the system performance simultaneously, we develop an asymmetrical transceiver architecture for massive MIMO systems in this paper by releasing the shackles on radio frequency (RF) chains. Specifically, we first develop the architecture for the asymmetrical transceiver where the number of receive RF chains is different from that of the transmit RF chains. Due to this unequal number of RF chains, channel inconsistency appears. To overcome the channel inconsistency and thus fully harness the system's downlink data transmission capability, we propose two uplink-to-downlink channel transfer algorithms. The cost and power consumption models for the asymmetrical transceiver are also developed and the uplink signal-to-noise loss due to the channel inconsistency is investigated. Through analyzing system spectral, cost, and energy efficiency, we demonstrate that the proposed asymmetrical transceiver-based massive MIMO system can achieve excellent downlink spectral efficiency while maintaining a reasonable energy efficiency.
翻译:即使大规模多投入多重产出(MIMO)理论上能够带来巨大的效益,但从理论上说它也会产生巨大的硬件复杂性和昂贵的硬件成本。为了在同时保持系统性能的同时解决这些问题,我们通过在无线电频率链上释放枷锁,在本文中为大型MIMO系统开发一个不对称的收发机结构。具体地说,我们首先为不对称的收发机设计一个结构,接收RF链的数目与传输RF链的数目不同。由于RF链条的数目不同,频道似乎不一致。为了克服频道不一致,从而充分利用系统的数据下链接传输能力,我们提出了两个上链到下链路传输算法。对不对称的收发机的成本和电耗模式也得到了开发,并调查了因频道不协调而造成的信号到噪音损失的上链。通过分析系统光谱、成本和能源效率,我们证明拟议的基于对称的移动器大型MIMO系统可以在保持合理的能源效率的同时实现极好的下链路光效率。