Research On High-efficiency And High-isolation Packaged Millimeter-wave Phased Array Antenna

The popularity of the fifth generation mobile communication technology(5G)has posed new challenges to the information throughput and latency levels of communication systems.Traditional mobile communication antennas are difficult to meet the three major application scenarios proposed by 5G,however,millimeter wave phased array antennas,as one of the key technologies for 5G,have various advantages such as wide frequency band and adjustable beam,and have become the focus of research in the industry.However,the current millimeter wave phased array antenna still has disadvantages,such as low array efficiency and dramatic scan gain attenuation.For this reason,this thesis carries out systematic research works on low-loss feed networks,array coupling suppression methods and package integration of millimeter wave phased arrays.The main contents are as follows.1.Research on high efficiency and high isolation phased array antenna based on simplified feed network: For the problem of low efficiency of millimeter wave phased array antenna,high-efficiency meta-surface phased array antenna based on simplified feed network is proposed,i.e.,using series feed and series-parallel hybrid feed to simplify the feed network,which solves the problems of complexity and high loss of the traditional parallel feed network and improves the antenna efficiency.Meanwhile,by analyzing the coupling distribution of the two antenna elements in the sub-array,it is determined that the coupling in its array is mainly surface wave coupling,so by loading the soft surface between the array elements,it effectively improves the isolation between antenna elements.2.Research on broadband high-efficiency phased array antenna based on the tapering feed network: To address the problem of narrow operating bandwidth of phased array antenna due to series feed network,a broadband high-efficiency phased array antenna based on the tapering feed network is proposed.At the same time,by analyzing the different coupling changes of antenna elements in the E-plane and H-plane,a spatial coupling offset decoupling method is proposed for the H-plane coupling suppression,i.e.a decoupling dielectric layer is loaded above the antenna array,and the inter-array coupling is offset by the partial reflection of electromagnetic waves from the dielectric layer,which effectively improves the coupling between the antenna elements.3.Research on broadband dual-polarized phased array antenna integrated in a package: In view of the design process limitation in the interconnection of millimeter wave phased array antenna and chip,this thesis proposes a dual-polarized low-profile broadband phased array antenna.That is,the bandwidth is extended by using stacked meta-surface units under the restriction of low profile;meanwhile,through accurate modelling analysis of the stripline transfer and coaxial transition structure in the package,the consistency of energy amplitude and phase in the interconnection process is realized to ensure the overall system performance.