In order to solve the problem of broadband field probes calibration with only selected discrete frequencies above 1 GHz, a sweep-frequency calibration technology based on a coaxial conical（co-conical） cell is resear...In order to solve the problem of broadband field probes calibration with only selected discrete frequencies above 1 GHz, a sweep-frequency calibration technology based on a coaxial conical（co-conical） cell is researched. Existing research is only qualitative because of the complexity of theoretical calculations. For designing a high performance cell, a mathematic model of high-order modes transmission is built according to the geometrical construction of co-conical. The associated Legendre control functions of high-order modes are calculated by using recursion methodology and the numerical calculation roots are presented with different half angles of inner and outer conductor. Relationship between roots and high-order modes transmission is analyzed, when the half angles of inner conductor and outer conductor are θ1=1.5136° and θ2=8° respectively, the co-conical cell has better performance for fewer transmitting high-order modes. The propagation process of the first three transmitting modes wave is simulated in CST-MWS software from the same structured co-conical. The simulation plots show that transmission of high-order modes appears with electromagnetic wave reflection, then different high-order mode transmission has different cut-off region and each cut-off region is determined by its cut-off wavelength. This paper presents numerical calculation data and theoretical analysis to design key structural parameters for the co-conical transverse electromagnetic wave cell（co-conical TEM cell）.展开更多
基金Supported by State Administration of Science Technology and Industry for National Defense,China(Grant No.JSJC2013204B301)
文摘In order to solve the problem of broadband field probes calibration with only selected discrete frequencies above 1 GHz, a sweep-frequency calibration technology based on a coaxial conical（co-conical） cell is researched. Existing research is only qualitative because of the complexity of theoretical calculations. For designing a high performance cell, a mathematic model of high-order modes transmission is built according to the geometrical construction of co-conical. The associated Legendre control functions of high-order modes are calculated by using recursion methodology and the numerical calculation roots are presented with different half angles of inner and outer conductor. Relationship between roots and high-order modes transmission is analyzed, when the half angles of inner conductor and outer conductor are θ1=1.5136° and θ2=8° respectively, the co-conical cell has better performance for fewer transmitting high-order modes. The propagation process of the first three transmitting modes wave is simulated in CST-MWS software from the same structured co-conical. The simulation plots show that transmission of high-order modes appears with electromagnetic wave reflection, then different high-order mode transmission has different cut-off region and each cut-off region is determined by its cut-off wavelength. This paper presents numerical calculation data and theoretical analysis to design key structural parameters for the co-conical transverse electromagnetic wave cell（co-conical TEM cell）.
