【摘要】 本文直接用电离层的虚高计算短波传递时延,经太阳黑子11年周期变化、周年变化和周日变化的改正,得到了在1000公里以内短波时延计算的实用公式为: τ=τ_o+τ_r+τ_s+τ_d,(以ms为单位) τ_o=2.900, τ_r=+0.0010R,±0.0007 τ_s=-0.048cos(2πt_s+28°.4),±0.014 ±6°.6 τ_d=0.105cos(2πt_d-63°.7)-0.102cos(4πt d/2+77°.0)±0.039 ±9°.6 ±0.039 ±2°.1 式中τ_o为根据BIH经验公式计算的时延值;τ_r为太阳黑子相对数R对时延的影响;τ_s为周年变化对时延的影响;τ_d为周日变化对时延的影响;t_s、t_d分别表示年和日的数。以武昌时辰站的实际收时结果比对,每天接收BPV时号八次,用此公式计算全年所有的收时精度均优于用BIH经验公式所获得的收时精度。更多还原

【Abstract】 In this paper, a practical formula for calculating the time lag of short wave being suited for a distance less than 1000 km is given. This formula derived directly is based on the virtual height of ionosphere. This virtual has been corrected by the periodic variations of sunspot for 11 years, and the annual and diurnal variations. It is as follows: τ=τ₀+τ_r+τ_s+τ_d（ms） τ₀=2.900 τ_r=0.0010R ±0.0007 τ_s=-0.048cos（2πt_s+28°.4） +0.014 +6°.6 τ_d=0.105cos（2πt_d-63°.7）-0.102cos(4πt_d/2+77°.0) ±0.039 ±9.6 ±0.039 ±2°.1 where, τ₀ is time lag value calculated by BIH empirical formula, τ_r is the effect of sunspot relative numbers on time lag, r_s is the effect of annual variation on time lag, τ_d is the effect of diurnal variation on time lag, t_s and t_d expresses the fraction of year and day respectively. Finally, an example has been calculated. Using practical data of Wuchang Time Observatory of IGG and by means of the formulae of BIH and （7b）, the compared results are given. The accuracy of results calculated by this formula is better than the accuracy calculated by BIH formula.更多还原