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  • Lizhong Song
  • 2010
This paper discussed a kind of conformal equiangular spiral antenna on the surface of the circular truncated cone and evaluated its radiation performances. Firstly, a planar equiangular spiral antenna is modeled, then it is projected onto a surface of a circular truncated cone and the conformal equiangular spiral antenna is formed. The discussed antenna has(More)
A compact fractal planar inverted F antenna (PIFA) for personal communication handset applications is proposed. The antenna covers GSM (0.89-0.96GHz), DCS (1.71-1.88GHz) and WLAN (2.445-2.455GHz) frequency bands. Overall size of the antenna is less than 48mm*21mm*1.5mm (1.51 cm3) makes it suitable for 4G handsets and can be easily designed and optimized by(More)
This paper presents a new approach to the discrete-time sliding mode control design based on the reaching law approach. A new discrete reaching law, which is stable at the origin, is proposed. Also, an algorithm for uncertainty estimation is developed. The proposed algorithm is applied to the control of a DC servo system. Simulation results show that the(More)
In order to save the space of aerocraft, the conformal antennas can be adopted, which also donpsilat affect the dynamics performance. This paper discusses a kind of cylindrical conformal Yagi-Uda antenna and estimates its radiation characteristics. The proposed cylindrical conformal Yagi-Uda antenna is composed of five conformal dipoles, which is mounted on(More)
An extremely low profile (0.022&#x03BB;<sub>c</sub>, &#x03BB;<sub>c</sub> is the wavelength of the central frequency) microstrip antenna with two H-shaped serial coupling slots for bandwidth enhancement is proposed in this paper. Compared with one coupling slot, a broader impedance bandwidth is available by employing two serial slots. Two coupling slots(More)
This paper researched a kind of cylindrically conformai microstrip patch antenna array with series feed network for the telemetry application on missile. The design procedure of feed network of the conformal microstrip patch antenna is simple, which suitable for the research and development of the large scale conformal antenna array. The required amplitude(More)
A global sliding-mode controller is developed for position and velocity control of AC servo system based on exponential acceleration/deceleration algorithm. The problem of position and velocity control in the system is analyzed first. On this foundation the exponential acceleration/deceleration algorithm is used to plan the velocity profile. At the same(More)