| 摘要 |
PURPOSE:To enlarge the range of an analyzable environmental condition and sonic wave frequency, by adaptably changing an environmental condition corresponding to the similar value of an inherent value desired to be calculated. CONSTITUTION:A sound field, when a sonic wave emitted from a point sound source propagates through an unhomogeneous medium (ocean), is shown as the cumulative sum of a normal mode wave and satisfies a Sommerfeld radiation condition. In calculating the inherent value of a normal mode, a proper boundary condition is set corresponding to the similar degree thereof to solve a boundary value problem. Environment information is inputted to a normal mode (NM) analytical means 2 from an environment information terminal 1 and a profile of a wave number and density is fabricated to be sent to a register group 3 while the means 2 sends the number of the axis of the channel (CH) of the NM-wave to a medium layer determining means 4 and the number of CH, upper and lower limit boundary numbers and an inherent value number are sent to an inherent value similar means 5. The means 2 calculates the inherent value and inherent vector corresponding to the similar value on the basis of these data to determine a sound field. |
