TY - JOUR
T1 - Hybrid MIMO Architectures for Millimeter Wave Communications
T2 - Phase Shifters or Switches?
AU - Mendez-Rial, Roi
AU - Rusu, Cristian
AU - Gonzalez-Prelcic, Nuria
AU - Alkhateeb, Ahmed
AU - Heath, Robert W.
N1 - Funding Information:
The work of N. González-Prelcic was supported by the Spanish Government within the European Regional Development Fund through the TACTICA Project and COMPASS Project under Grant TEC2013-47020-C2-1-R. The work of R. W. Heath, Jr., was supported in part by the National Science Foundation under Grant NSF-CCF-1319556 and in part by Nokia.
Publisher Copyright:
© 2013 IEEE.
PY - 2016
Y1 - 2016
N2 - Hybrid analog/digital multiple-input multiple-output architectures were recently proposed as an alternative for fully digital-precoding in millimeter wave wireless communication systems. This is motivated by the possible reduction in the number of RF chains and analog-to-digital converters. In these architectures, the analog processing network is usually based on variable phase shifters. In this paper, we propose hybrid architectures based on switching networks to reduce the complexity and the power consumption of the structures based on phase shifters. We define a power consumption model and use it to evaluate the energy efficiency of both structures. To estimate the complete MIMO channel, we propose an open-loop compressive channel estimation technique that is independent of the hardware used in the analog processing stage. We analyze the performance of the new estimation algorithm for hybrid architectures based on phase shifters and switches. Using the estimate, we develop two algorithms for the design of the hybrid combiner based on switches and analyze the achieved spectral efficiency. Finally, we study the tradeoffs between power consumption, hardware complexity, and spectral efficiency for hybrid architectures based on phase shifting networks and switching networks. Numerical results show that architectures based on switches obtain equal or better channel estimation performance to that obtained using phase shifters, while reducing hardware complexity and power consumption. For equal power consumption, all the hybrid architectures provide similar spectral efficiencies.
AB - Hybrid analog/digital multiple-input multiple-output architectures were recently proposed as an alternative for fully digital-precoding in millimeter wave wireless communication systems. This is motivated by the possible reduction in the number of RF chains and analog-to-digital converters. In these architectures, the analog processing network is usually based on variable phase shifters. In this paper, we propose hybrid architectures based on switching networks to reduce the complexity and the power consumption of the structures based on phase shifters. We define a power consumption model and use it to evaluate the energy efficiency of both structures. To estimate the complete MIMO channel, we propose an open-loop compressive channel estimation technique that is independent of the hardware used in the analog processing stage. We analyze the performance of the new estimation algorithm for hybrid architectures based on phase shifters and switches. Using the estimate, we develop two algorithms for the design of the hybrid combiner based on switches and analyze the achieved spectral efficiency. Finally, we study the tradeoffs between power consumption, hardware complexity, and spectral efficiency for hybrid architectures based on phase shifting networks and switching networks. Numerical results show that architectures based on switches obtain equal or better channel estimation performance to that obtained using phase shifters, while reducing hardware complexity and power consumption. For equal power consumption, all the hybrid architectures provide similar spectral efficiencies.
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U2 - 10.1109/ACCESS.2015.2514261
DO - 10.1109/ACCESS.2015.2514261
M3 - Article
AN - SCOPUS:84979849127
SN - 2169-3536
VL - 4
SP - 247
EP - 267
JO - IEEE Access
JF - IEEE Access
M1 - 7370753
ER -