利用我国2011年1月和7月10条斜测电路的F2层基本最高可用频率（MUF）月中值数据，与ITU-RP．434方法计算的F2层基本MUF进行了比较，分析了该方法在中国地区的适用性。结果表明：ITU—RP．434方法在中国地区具有较好的适用性，但在某些电路的个别时段偏差较大。其中，1月份在中纬地区日出时段，该方法给出的基本MUF与月中值相比偏低209／6～30％，在日落时段则偏高20％～30％；低纬地区夜间时段两者的相对偏差较大，最大值达到40％．7月份，该方法的结果与各条电路的实测结果基本一致，相对偏差在～10％～20％之间。上述结果对短波通信的选频等具有一定的指导意义。%The F2 layer basic maximum usable frequency (MUF) value calculated by the ITU-R P. 434 method is compared with the median of measurement for 10 oblique circuits in China during January and July, 2011, and then the applicability of ITU-R P. 434 inChina area is analyzed. It is shown that the method has good applicability in China, except that sometimes there are certain error in some circuits. In January, MUF value calculated by ITU-R P. 434 is less than the median of meas- urement by 20%-30% in mid-latitude during sunrise, while it is larger by 20%- 30% during sunset. The relative difference between these two values at low-latitude is larger during mid-night, reaching about 400/00. In July, the two values agree with each other quite well in all circuits, and the relative differences are among about -10%-20%. This result is valuable to HF applications such as the frequency selection.
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