ローランに於ける空間波の伝播誤差特性 : II平均値の意義(日本航海学会第17回講演会)

抄録

One of the most important cause of the errors at the Loran system is the sky wave propagation error. This error is unavoidable by any careful observation. We investigated the significance of the mean values of several Loran readings and find that the sky wave propagation errors are considerably reduced by taking the mean values instead of the observed values. For example, when the probable error of observed values is 2.18μ.s., that of the mean value of twice observations is 1.77μ.s. (corresponding to 81% of that of the observed) and that of the mean values of five times is 1.48μ.s. (corresponding to 68%). In the other hand the errors by the navigation of own ship are increased, because the more the number of observations are, the longer the time required is. These errors, however, can be avoided by suitable correction.