The Miniaturization and Electrical Performance Improvement of Base Station Array Antenna with Artificial Magnetic Conductor

摘要

As a wireless communication system is continuously evolving to support various services, many researches on improving the performance of antennas have been conducted. To satisfy the demand for miniaturization and multifunctional of terminals, intennas and multi-band antennas have been introduced. Recently, a research on smart antennas which can affect frequency usage and radiation pattern has been progressed. Specially, these researches have actively conducted in base station antenna [1]. A base station array antenna consists of a dipole array and a reflector to obtain high gain up to 13dBi. However, there are some drawbacks in conventional base station array antenna. Generally, a conductive surface is used as a reflector in conventional base station array antenna and its reflection phase is 180° on the surface. In that case, a quarter-wavelength distance between the dipole array and the conductive surface is required to prevent the destructive interaction of forward/backward waves. In addition, a secondary radiation caused at the corner of conductive surface can reduce total gain of the conventional base station array antenna. Therefore, an alternative of the conductive surface is needed to overcome the limitation of the conventional base station array antenna [2], [3].Artificial magnetic conductor (AMC) has been investigated by focusing on the low profile, radiation pattern of dipole antennas. Due to its 0° reflection phase, the base station array antenna can be designed in low profile. In addition, the front back ratio (FBR) of base station array antenna can be improved by the high impedance of AMC. Therefore, a base station array antenna with AMC in PCS frequency band is proposed.