| With the rapid development of the Micro- Electro-Mechanical System technologies, The Radio Frequency Micro -Electronic -Mechanical System will advance enormously micromation, integration and intelligentize. The researchers have focused on the RF-MEMS technology at present. It has quite wide application prospect and market.Micromachined RF-MEMS antenna is one of the key devices in RF-MEMS. It will become an inevitable development trend of its micromation and broadband, multi-band, intelligentize and integration. It is more and more complexity of its structure and electromagnetic surroundings, it is difficult to solve these problems adopting traditional theories. Therefore, we must depend on advance time-domain simulation methods. Under the support of the Major State Basic Research Development Program ("973"Program) on "Study of Relevant Issues of Micrometer- Scale RF Components" of "Study of Integrated Micro- Optical-Electronic-Mechanical System" (Subject No. G1999033105), this thesis studies the theory of time-domain modeling and simulation of the micromachined antenna. Design and fabricate novel micromachined antennas. The novel theories of time-domain simulation are used for modeling and analyzing the novel micromachined patch antenna for the first time, it saves more than 60% CPU time or computer memory. The thesis achieve breakthrough on the theory of time-domain simulation and characteristic parameter optimization of micromachined antennas, it has great theoretical signification and practical value.A uniform system of FDTD(m,n) based on matrix theory is founded, and its key technologies, such as numeric stability and accuracy, dispersion and absorbing boundary conditions, etc. are studied. The stability condition of FDTD(4,4) has been proved for the first time. The transformative algorithms of FDTD (ADI-FDTD(4,4) and MRTD) are studied. ADI-FDTD(2,2) algorithm is extended to ADI-FDTD(4,4) for the first time. It has been proved that ADI-FDTD(4,4) algorithm is still unconditional stability. Therefore, the time-step size can be arbitrarily set within the limitation of numerical errors. It can economize 2/3 CPU computation time, and improve computational efficiency. The difficult problem that traditional FDTD cannot be applied to quite thin object is solved. Based on scale functions and wavelet functions synchronously, the MRTD formula of electromagnetic components in PML medium is outspreaded for the first time. Applying ADI technology into MRTD method, and deriving ADI-MRTDalgorithm formula in PML medium for the first time. Applying the time-domain simulation theories to micromachined antenna, it demonstrates the incomparable superiority of the innovative algorithm. The innovative algorithm has not only raised the simulation ability of the complicated structure, and expanded the range of application of FDTD algorithm for other MEMS elememts, but also economized resources of the computer effectively.Through adding probe, shorted-wall, additional microstrip line or parasitic patch, and adopting stacked structure, photonic band gap or slot-loaded, the novel micromachined antennas are designed and fabricated, and succeeded in realizing miniaturization, broadband or dual-band performance characteristics. The bandwidth reaches 23% of the novel micromachined antenna. The size of novel antenna minish to λ/16, it is only 1/8 times of traditional half wavelength patch antenna. The methods of measurement and error control and adjust of measure course about scattering parameter, impedance, radiation pattern, power, efficiency and gain, etc. are given. The time-domain near field measure method that develops fast in recent years is researched, expatiating the importance of time-domain near field measure method for micro-scale RF-MEMS antenna. Discussing the errors modeling and manufacture process and putting forward the methods reducing or eliminating the errors.The research of the theories of tradition FDTD and the theories of radiation and coupling, miniaturization, broadband and multi-band work of micromachined antenna in mi...
|
PDF Full Text Request