In this paper, the performance of hybrid precoding is investigated for mmWave massive MIMO systems with different antenna arrays. The hybrid precoding with partially connected architecture (PCA) is adopted. The spectr...In this paper, the performance of hybrid precoding is investigated for mmWave massive MIMO systems with different antenna arrays. The hybrid precoding with partially connected architecture (PCA) is adopted. The spectral efficiency (SE) and received energy efficiency (EE) are investigated by considering four types of antenna arrays, including uniform linear array (ULA), uniform rectangular planar array (URPA), uniform hexagonal planar array (UHPA), and uniform circular planar array (UCPA), respectively. We focus on analysis at the antenna response vector and utilize the idea of orthogonal matching pursuit algorithm to seek the optimal hybrid precoder. Furthermore, the trade-off of precoding architectures is studied between SE and received EE. Simulation results show that if the uniform planar array antenna is more concentrated, the SE and receive EE will be higher. Considering SE and received EE, the performance of planar arrays outperform linear array. There exist different optimal radio-frequency chain numbers to maximize the SE for planar array and linear array. In addition, the PCA can achieve relatively higher received EE while the SE is close to the fully connected architecture and the full digital architecture.展开更多
Structural colors with high saturation,large gamut,high resolution,and tunable color are expected in practical applications.This work explores the generation of tunable structural color based on transmission metasurfa...Structural colors with high saturation,large gamut,high resolution,and tunable color are expected in practical applications.This work explores the generation of tunable structural color based on transmission metasurfaces.The designed metasurfaces consist of rectangular nanoholes etched in silver film,which is deposited on the stretchable polydimethylsiloxane(PDMS)substrate.The smaller separation of adjacent nanoholes makes the resolution of metasurface reach 63,500 dpi.The color gamut of the nanostructures reaches 146.9%sRGB.We also perform a comparison with the case on the glass substrate and analyze the incident polarization condition and the coating film of polymethyl methacrylate(PMMA).The ultra-thin structure,high resolution,highperformance structural colors,and convenient transmission mode provide broad application prospects for metasurfaces in color displaying,color printing,and color holographic imaging.展开更多
基金supported by the National Natural Science Foundation of China (No.61961018)the Jiangxi Province Foundation for Distinguished Young Scholar (No.20192BCB23013)+1 种基金the Jiangxi Province Natural Science Foundation of China (No.20171BAB202001, 20192ACB21003)the Science Program of Jiangxi Educational Committee (No.GJJ180307)
文摘In this paper, the performance of hybrid precoding is investigated for mmWave massive MIMO systems with different antenna arrays. The hybrid precoding with partially connected architecture (PCA) is adopted. The spectral efficiency (SE) and received energy efficiency (EE) are investigated by considering four types of antenna arrays, including uniform linear array (ULA), uniform rectangular planar array (URPA), uniform hexagonal planar array (UHPA), and uniform circular planar array (UCPA), respectively. We focus on analysis at the antenna response vector and utilize the idea of orthogonal matching pursuit algorithm to seek the optimal hybrid precoder. Furthermore, the trade-off of precoding architectures is studied between SE and received EE. Simulation results show that if the uniform planar array antenna is more concentrated, the SE and receive EE will be higher. Considering SE and received EE, the performance of planar arrays outperform linear array. There exist different optimal radio-frequency chain numbers to maximize the SE for planar array and linear array. In addition, the PCA can achieve relatively higher received EE while the SE is close to the fully connected architecture and the full digital architecture.
基金National Natural Science Foundation of China(10874105)Natural Science Foundation of Shandong Province(ZR2020KA009)。
文摘Structural colors with high saturation,large gamut,high resolution,and tunable color are expected in practical applications.This work explores the generation of tunable structural color based on transmission metasurfaces.The designed metasurfaces consist of rectangular nanoholes etched in silver film,which is deposited on the stretchable polydimethylsiloxane(PDMS)substrate.The smaller separation of adjacent nanoholes makes the resolution of metasurface reach 63,500 dpi.The color gamut of the nanostructures reaches 146.9%sRGB.We also perform a comparison with the case on the glass substrate and analyze the incident polarization condition and the coating film of polymethyl methacrylate(PMMA).The ultra-thin structure,high resolution,highperformance structural colors,and convenient transmission mode provide broad application prospects for metasurfaces in color displaying,color printing,and color holographic imaging.
