Research On Transmission Array Based On Broadband Microstrip Unit

Wireless emergency communication,electronic countermeasures,satellite communication,remote sensing detection and intelligent vehicle technologies are developing rapidly with the development of wireless communication.As an important subsystem of these equipment,antenna plays an important role.Modern wireless communication system not only requires the antenna to have high gain,but also needs its working broadband,simple structure,low cost and wide beam scanning characteristics.Array antenna is one of the important methods to realizes the above idea.In this context,the design method of wideband microstrip transmitarray based on quasi yagi antenna unit cell and vivaldi antenna unit cell as well as the characteristics of wideband width,wide beam scanning and filtering are studied in this paper.The research results of this paper are as follows:1.Research on transmitarray antenna based on quasi yagi antenna unit cell.In this paper,a transmitarray based on quasi yagi antenna unit cell is implemented by a receive-transmit structure.The unit of the transmitarray is composed of two quasi yagi antennas which connect their feeding line and grounding boards together in a back-to-back structure.The feed of the transmitarray is a single end-fire quasi-yagi antenna.The wideband and wide-beam scanning characteristics are realized by optimizing the size of the unit cell and the focal diameter ratio of the transmitarray,the 1-dB bandwidth reaches 13.81%and the scan angle in E-Plane reaches±56°.The filtering characteristics of the transmitarray are further extended on the original broadband characteristics,and the filtering characteristics of the transmitarray are realized by replacing the original end-fire yagi antenna feeding with the feeding with filtering characteristics,the out-band-rejection of the 3-dB side frequency point within the range of 0.3GHz can reach about 24.2dB.2.Research on transmitarray antenna based on vivaldi antenna unit cell.In this paper,a transmitarray based on vivaldi antenna unit cell is implemented with a receive-transmit structure.The unit of the transmitarray is composed of two vivaldi antennas which connect their feeding line and grounding boards together in a back-to-back structure.The feed of the transmitarray is a vivaldi antenna with a single end-fire.The wideband and wide-beam scanning characteristics are realized by optimizing the size of the unit cell and the focal diameter ratio of the transmitarray,the 1-dB bandwidth reaches 21.42%and the scan angle in H-Plane reaches ±44°.The filtering characteristics of the transmitarray are further extended on the original broadband characteristics,and the filtering characteristics of the transmitarray are realized by replacing the original end-fire yagi antenna feeding with the feeding with filtering characteristics,the out-band-rejection of the 3-dB side frequency point within the range of 0.3GHz can reach about 24.8dB.