The Design of UWB Antenna for Mobile Phone and the Antenna Influence on Human Head Model

In order to improve the performance of the antenna at low frequency,short circuit branch and coupling feed structure are introduced into the folded broadband single antenna in this paper,then resonant frequency is merged into the antenna using method of stagger tuning,finally,a UWB antenna is designed to w ork betw een 800 MHz ~ 2700 MHz. Analysis are conducted to determine the antenna's properties. The short-circuit w ire location,feeding point location and the length of folded strip are discussed in detail. The SAR is calculated by HFSS simulation softw are w hile the antenna is close to a 3D human head model. The research results show that the antenna can cover eight commonly used commercial frequency bands at present,and electromagnetic radiation of the antenna has tiny influence on the human head model.

基于逻辑门限值的爆胎车辆制动仿真研究

为研究汽车防抱死制动系统(ABS)在爆胎工况下的有效性,基于逻辑门限值控制设计了ABS控制系统,结合动力学软件CarSim与Simulink设计控制系统,以轮胎滑移率为控制对象,以纵向制动距离和横向偏移量为衡量标准,对正常驾驶和爆胎工况下的汽车采用不同的制动方式进行仿真研究。结果表明,在汽车正常行驶和爆胎工况下,逻辑门限值ABS控制器都能起到实时的制动效果,但不同的制动策略有着较为明显的差别;爆胎工况下,汽车的纵向制动距离较正常行驶的汽车有所延长,此时前左、右侧控制策略中的四轮独立控制策略的轮胎没有出现抱死现象,制动效果最佳。