To overcome the mutual coupling (MC) of multiple antennas in millimeter wave (mmWave) communication systems, a novel beam design method with low complexity is proposed in this paper. Firstly, an equivalent channel mod...To overcome the mutual coupling (MC) of multiple antennas in millimeter wave (mmWave) communication systems, a novel beam design method with low complexity is proposed in this paper. Firstly, an equivalent channel model incorporating the effect of MC is analyzed and established, and then an optimal precoding / combiner vector for beamforming is derived. On this basis, by using greedy geometric (GG) algorithm, a novel hybrid beam design method is proposed. Finally, the performance of proposed method is analyzed and compared with other traditional ones. The simulation results show that the proposed method has better suppression of the MC effect as well as lower complexity.展开更多
In this paper we present the design of a leaky wave antenna based on Substrate Integrated Waveguide (SIW) loaded by Complementary Split Ring resonator (CSRR). The proposed antenna is designed for 5G application with a...In this paper we present the design of a leaky wave antenna based on Substrate Integrated Waveguide (SIW) loaded by Complementary Split Ring resonator (CSRR). The proposed antenna is designed for 5G application with a center frequency around 28 GHz. The antenna is implemented on Roger RT/Duriod 5880. The loading CSRRs are designed to resonate at 28 GHz. The design is simulated by using both High-Frequency Simulation Software (HFSS) and Computer Simulation Technology (CST) for verification. Experimental measurements are also presented.展开更多
磁层多尺度卫星(MMS-1)在日侧06:30 MLT(磁地方时,Magnetic Local Time)外磁层大于2Re(L为7.5~10.1)的范围内观测到多达21个波包的准周期性电磁离子回旋波(EMIC)事件。超低频(ULF)波和能量质子温度各向异性准周期性增强也被同步观测到...磁层多尺度卫星(MMS-1)在日侧06:30 MLT(磁地方时,Magnetic Local Time)外磁层大于2Re(L为7.5~10.1)的范围内观测到多达21个波包的准周期性电磁离子回旋波(EMIC)事件。超低频(ULF)波和能量质子温度各向异性准周期性增强也被同步观测到。频率分析显示,ULF波的周期、质子各向异性周期和EMIC波包的周期非常接近。MMS-4卫星在约1 h后经过附近空间区域,研究发现随着ULF波的幅度减弱,EMIC波包的准周期性也逐渐减弱。研究结果为ULF波在日侧外磁层调制质子各向异性从而产生周期性EMIC波包提供了完整的观测证据链。同时,观测结果进一步证明,这种ULF波调制的EMIC波包能够在大于2Re的空间尺度内发生,且能够持续存在于几个小时以上的时间尺度。展开更多
The application scenarios of railway radio communication are complex,while the existing narrowband communication such as GSM-R and radio train dispatching system fails to meet the requirements of service application d...The application scenarios of railway radio communication are complex,while the existing narrowband communication such as GSM-R and radio train dispatching system fails to meet the requirements of service application development.The carrying capacity of railway 5G-R has been greatly improved,mainly for wide-area train-ground communication services such as dispatching communication,train control and train operation safety monitoring.However,for large passenger stations,freight yards,maintenance bases and other places with densely populated railway operators,it is unable to carry overall railway service applications limited by the spectrum bandwidth of 5G private networks,so it is necessary to consider various radio technologies for supplementation.This paper also elaborates the railway service application scenarios,analyzes the characteristics of radio communication technologies such as 5G mmWave and the 6th-generation wireless LAN technology(Wi-Fi6),and discusses the schemes of multi-technology convergence carrying railway 5G service applications.展开更多
基金supported by Aeronautical Science Foundation of China (2017ZC52021)the Major Program of National Natural Science Foundation of China (61827801)
文摘To overcome the mutual coupling (MC) of multiple antennas in millimeter wave (mmWave) communication systems, a novel beam design method with low complexity is proposed in this paper. Firstly, an equivalent channel model incorporating the effect of MC is analyzed and established, and then an optimal precoding / combiner vector for beamforming is derived. On this basis, by using greedy geometric (GG) algorithm, a novel hybrid beam design method is proposed. Finally, the performance of proposed method is analyzed and compared with other traditional ones. The simulation results show that the proposed method has better suppression of the MC effect as well as lower complexity.
文摘In this paper we present the design of a leaky wave antenna based on Substrate Integrated Waveguide (SIW) loaded by Complementary Split Ring resonator (CSRR). The proposed antenna is designed for 5G application with a center frequency around 28 GHz. The antenna is implemented on Roger RT/Duriod 5880. The loading CSRRs are designed to resonate at 28 GHz. The design is simulated by using both High-Frequency Simulation Software (HFSS) and Computer Simulation Technology (CST) for verification. Experimental measurements are also presented.
文摘磁层多尺度卫星(MMS-1)在日侧06:30 MLT(磁地方时,Magnetic Local Time)外磁层大于2Re(L为7.5~10.1)的范围内观测到多达21个波包的准周期性电磁离子回旋波(EMIC)事件。超低频(ULF)波和能量质子温度各向异性准周期性增强也被同步观测到。频率分析显示,ULF波的周期、质子各向异性周期和EMIC波包的周期非常接近。MMS-4卫星在约1 h后经过附近空间区域,研究发现随着ULF波的幅度减弱,EMIC波包的准周期性也逐渐减弱。研究结果为ULF波在日侧外磁层调制质子各向异性从而产生周期性EMIC波包提供了完整的观测证据链。同时,观测结果进一步证明,这种ULF波调制的EMIC波包能够在大于2Re的空间尺度内发生,且能够持续存在于几个小时以上的时间尺度。
文摘The application scenarios of railway radio communication are complex,while the existing narrowband communication such as GSM-R and radio train dispatching system fails to meet the requirements of service application development.The carrying capacity of railway 5G-R has been greatly improved,mainly for wide-area train-ground communication services such as dispatching communication,train control and train operation safety monitoring.However,for large passenger stations,freight yards,maintenance bases and other places with densely populated railway operators,it is unable to carry overall railway service applications limited by the spectrum bandwidth of 5G private networks,so it is necessary to consider various radio technologies for supplementation.This paper also elaborates the railway service application scenarios,analyzes the characteristics of radio communication technologies such as 5G mmWave and the 6th-generation wireless LAN technology(Wi-Fi6),and discusses the schemes of multi-technology convergence carrying railway 5G service applications.
