parabolic arch meaning in English

抛物线拱

A new waveguide made of changing a wide wall of a rectangular waveguide to a uniform curved wall is called conformal waveguide . a kind of expression of approximate solution for domain mode of the new waveguide , including symmetric , unsymmetric arc , parabolic arch , hyperbolic arch , elliptic arch , etc . , is constructed by using boundary condition of mental waveguide , variational method and boundary element method . by using the equivalence principle , an approximate calculating formula for equivalent resonant conductance of a narrow longitudinal halfwavelength slot cut in the curved wall of the unsymmetric arcrectangular waveguide is derived , and the result is shown . although this solution is approximate , it can solve the problem in designing the slotted antenna of such conformal waveguide
把矩形波导一个宽面外突成均匀曲面构成的新波导统称为共形波导.利用金属波导边界条件、变分法、边界元素法构造这种新波导中主模场的一种近似解表达式，包括曲面横截线为对称、非对称圆弧，抛物线弧，双曲线弧，椭圆弧等.然后根据等效原理，推导非对称圆弧矩形波导曲面上窄的纵向半波长缝隙的等效谐振电导的近似计算公式，给出计算曲线.这种解虽然是近似的，但却能解决这类共形波导缝隙天线的工程设计