A convolutional weighting (CW) scheme applied to a half-wavelength spacing array was proposed for multi-user system to joint STBC (space time block ceding) and beam forming (BF). The transmitting beam is equival...A convolutional weighting (CW) scheme applied to a half-wavelength spacing array was proposed for multi-user system to joint STBC (space time block ceding) and beam forming (BF). The transmitting beam is equivalent to the product of two sub-beams. One is used to realize interference suppression, while the other is employed to form a couple of uncorrelated channels from base station (BS) to the desited user (to meet the requirement of STBC) and to maximize SINR (signal-to-interference-plus noise ratio) at the desired receiver. As an optimum combination of STBC and beam forming, the proposed scheme can achieve both full diversity order of STBC and array gain of BF. Meanwhile, it can also effec- tively restrain multi-user interference by nulling. Simulation results show that the proposed scheme can significantly improve the BER (Bit Error Rate) performance and enhance system capacity as compared with the conventional eigen-beamforming (EBF) technique applied to a half-wavelength spacing array.展开更多
The construction of a barrier-free environment is an important measure that guarantees the safety,right-of-way,and interests of the disabled,the elderly,and other mobility disadvantaged groups.It is also an indispensa...The construction of a barrier-free environment is an important measure that guarantees the safety,right-of-way,and interests of the disabled,the elderly,and other mobility disadvantaged groups.It is also an indispensable part of the low-carbon urban transportation and a necessary way to protect the rights of mobility disadvantaged groups in green travel.In this paper,the researchers conducted life log surveys on the travels of 10 wheelchair users residing in Beijing with IoT Inspector,a self-developed,wheelchairmountable intelligent sensing device.Wheelchair users’travel preferences and reasons were then analyzed using the image and textual data from the surveys.Combined with a mapping workshop,a comparative analysis was performed on the bumpiness of sidewalk paving materials.The study found that wheelchair travelers’preferred non-motor lanes over sidewalks;substandard curb ramps,unleveled tree pools,limited access widths,and bumpy pavement were the main problems faced by wheelchair users in sidewalk accessibility.In addition,the study explores the inclusive needs and challenges of non-motorized right-of-way for new transportation means at urban planning and traffic management levels.Based on multi-sourced data,this paper discusses the possibility of assessing urban barrier-free environment and representing a narrative of the needs of mobility disadvantaged groups,so as to provide practical experience and technical support to the improvement strategies of adaptive roads.展开更多
基金Supported by the National Natural Science Foundation of Chin(No. 60302020).
文摘A convolutional weighting (CW) scheme applied to a half-wavelength spacing array was proposed for multi-user system to joint STBC (space time block ceding) and beam forming (BF). The transmitting beam is equivalent to the product of two sub-beams. One is used to realize interference suppression, while the other is employed to form a couple of uncorrelated channels from base station (BS) to the desited user (to meet the requirement of STBC) and to maximize SINR (signal-to-interference-plus noise ratio) at the desired receiver. As an optimum combination of STBC and beam forming, the proposed scheme can achieve both full diversity order of STBC and array gain of BF. Meanwhile, it can also effec- tively restrain multi-user interference by nulling. Simulation results show that the proposed scheme can significantly improve the BER (Bit Error Rate) performance and enhance system capacity as compared with the conventional eigen-beamforming (EBF) technique applied to a half-wavelength spacing array.
文摘The construction of a barrier-free environment is an important measure that guarantees the safety,right-of-way,and interests of the disabled,the elderly,and other mobility disadvantaged groups.It is also an indispensable part of the low-carbon urban transportation and a necessary way to protect the rights of mobility disadvantaged groups in green travel.In this paper,the researchers conducted life log surveys on the travels of 10 wheelchair users residing in Beijing with IoT Inspector,a self-developed,wheelchairmountable intelligent sensing device.Wheelchair users’travel preferences and reasons were then analyzed using the image and textual data from the surveys.Combined with a mapping workshop,a comparative analysis was performed on the bumpiness of sidewalk paving materials.The study found that wheelchair travelers’preferred non-motor lanes over sidewalks;substandard curb ramps,unleveled tree pools,limited access widths,and bumpy pavement were the main problems faced by wheelchair users in sidewalk accessibility.In addition,the study explores the inclusive needs and challenges of non-motorized right-of-way for new transportation means at urban planning and traffic management levels.Based on multi-sourced data,this paper discusses the possibility of assessing urban barrier-free environment and representing a narrative of the needs of mobility disadvantaged groups,so as to provide practical experience and technical support to the improvement strategies of adaptive roads.