Design Of The Interface Of Board-to-board RF Coaxial Connectors

With the rapid development of interconnection systems, the board-to-board RF coaxial connectors is finding increasingly wide applications in wireless interconnection systems. Given the current the trend for wireless devices market, the devices for the connectors requirement is smaller, lighter and cheaper. The board-to-board RF coaxial connectors are going in the direction of high tolerance, high power and miniaturization. At present, there are few board-to-board RF coaxial connectors in market of our country, so it is of great importance to study and design our own intellectual-property rights in the interface of board-to-board RF coaxial connector.The main research in this thesis can be summarized as follows:1. Several compensating methods are analyzed through simulations. These methods are aimed at the discontinuity of impedance, and in light of the simulation examples, the validity of the compensation methods is verified. According to the time domain function of HFSS, the design of printed circuited board(PCB) pad for a kind of board-to-board RF coaxial connector is presented, and the simulation results are optimized.2. On the basis of analysis and comparison of the advantages and disadvantages of the interface of existing board-to-board connectors, a brand new design of interface of board-to-board connectors is presented. According to this new interface, the lengthened SMP board-to-board RF connector is proposed in this thesis. This connector has a larger axial tolerance for parallel circuit board to circuit board. Maximum axial tolerance of the lengthened SMP connector can reach 1.2 millimeter(mm), which is 200% more than the standard SMP connector. This connector is fabricated and measured, the experimental results show that the design has a good electrical performance up to 6GHz and meet the design specific requirements.3. According to the new interface, the design of RF adapter lengthened SMP-SMA3.5 is presented. This thesis proposed a detail design procession. In this design, the impedance discontinuity of the dimensional change of inner conductor and the step surface of insulator is eliminated by displaced compensation and coplanar compensation respectively. The simulation result shows that the VSWR of the adapter is improved after compensation. The test results of the fabricated adapter show that the VSWR of adapter is below 1.2 up to 10 GHz meeting the design specifications.