The Application Of Microstrip Array Antenna In Mobile Communication

With the development of communication technology, mobile communication has been closely connected with people’s life. Antenna is a very important component of the Communication system, because it can affect the quality of the whole communication system. Usually, it is difficult for an antenna to be used in the long-distance communication system for its limited gain. Therefore, an antenna array is usually needed in long-distance communication system. In this paper, application of microstrip array antenna in the navigation satellite system and cellular mobile communication system are introduced. Two array antennas for navigation satellite system and a multiband microstrip array antenna for cellular mobile communication system are proposed. The main issues discussed include the following five aspects.(1) The theory of circular polarization and the design of circular polarized microstrip antenna are presented. (2) The navigation satellite system’s element antenna design. From the theory of circular polarization and high gain which are needed for antenna of navigation satellite system, some antennas’structures and feeding models are analyzed. A stacked patch antenna with a small size and a high dielectric constant, which could work in dual band is presented. The results of simulation show that:at both bands, the antenna is right-hand circularly polarized (RHCP), the axial ratio of normal line direction are both less than1.5, the gains are both more than4.6dB,and the VSWR are both less than1.4.The element antenna’s size is100X100X6mm3.(3) The navigation satellite system’s antenna array design. Two kinds of formation are presented:the linear array and the planar array. And the structure of feeding network is studied. To illustrate the differences between linear antenna array and planar antenna array, the1×4linear antenna array and the2×2plane antenna array with the same element are designed. These two kinds of array antennas are studied by simulation software in terms of the array antennas’gain, polarization axial ratio, S parameter, size of the whole structure and so on.(4) Cellular mobile communication system’s Element antenna design. From the theory of multiband, an antenna for cellular mobile communication system is proposed. The results of simulation of HFSS show that:between1700MHz and2700MHz, The proposed antenna achieved a gain of4.5dB, a directional radiation pattern and maximum VSWR of1.92. The antenna is suitable for cellular mobile communication system.(5) Cellular mobile communication system’s antenna array design. A1×4linear antenna array is designed. And the characters of the antenna array are achieved through HFSS.Above all, the main conclusions are reached and future work is looked forward to.