The mismatch of ill-phase and quadrature channels in quadrature receiver affects and constrains radar detection performance in coherent radar. It is necessary to keep the in-phase and quadrature branches symmetrical. ...The mismatch of ill-phase and quadrature channels in quadrature receiver affects and constrains radar detection performance in coherent radar. It is necessary to keep the in-phase and quadrature branches symmetrical. In this letter, an adaptive method t.o detect imbalance parameters is derived by means of evaluating channel errors from the received signal .sequences. No matter how the bias degree of the gain and phase errors in I/Q channels are. the proposed adaptive scheme can obtain good calibration results. And the inquired calculations are only a few multiplications and additions. No need of a special test signal, the introduced method is simple to implement and easy to operate.展开更多
Pedestrian's road-crossing model is the key part of micro-simulation for mixed traffic at signalized intersection.To reproduce the crossing behavior of pedestrians,the microscopic behaviors of the pedestrians pass...Pedestrian's road-crossing model is the key part of micro-simulation for mixed traffic at signalized intersection.To reproduce the crossing behavior of pedestrians,the microscopic behaviors of the pedestrians passing through the crosswalk at signalized intersection were analyzed.A pedestrian's decision making model based on gap acceptance theory was proposed.Based on the field data at three typical intersections in Beijing,China,the critical gaps and lags of pedestrians were calibrated.In addition,considering pedestrian's required space,a modification of the social force model that consists of a self-deceleration mechanism prevents a simulated pedestrian from continuously pushing over other pedestrians,making the simulation more realistic.After the simple change,the modified social force model is able to reproduce the fundamental diagram of pedestrian flows for densities less than 3.5 m-2 as reported in the literature.展开更多
文摘The mismatch of ill-phase and quadrature channels in quadrature receiver affects and constrains radar detection performance in coherent radar. It is necessary to keep the in-phase and quadrature branches symmetrical. In this letter, an adaptive method t.o detect imbalance parameters is derived by means of evaluating channel errors from the received signal .sequences. No matter how the bias degree of the gain and phase errors in I/Q channels are. the proposed adaptive scheme can obtain good calibration results. And the inquired calculations are only a few multiplications and additions. No need of a special test signal, the introduced method is simple to implement and easy to operate.
基金Project(70972041)supported by the National Natural Science Foundation of ChinaProject(20100009110010)supported by the PhD Programs Foundation of Ministry of Education of ChinaProject(2011YJS246)supported by Fundamental Research Funds for the Central Universities of China
文摘Pedestrian's road-crossing model is the key part of micro-simulation for mixed traffic at signalized intersection.To reproduce the crossing behavior of pedestrians,the microscopic behaviors of the pedestrians passing through the crosswalk at signalized intersection were analyzed.A pedestrian's decision making model based on gap acceptance theory was proposed.Based on the field data at three typical intersections in Beijing,China,the critical gaps and lags of pedestrians were calibrated.In addition,considering pedestrian's required space,a modification of the social force model that consists of a self-deceleration mechanism prevents a simulated pedestrian from continuously pushing over other pedestrians,making the simulation more realistic.After the simple change,the modified social force model is able to reproduce the fundamental diagram of pedestrian flows for densities less than 3.5 m-2 as reported in the literature.
