引入Volterra级数自适应混沌预报方法,实现了高频通信最大可用频率的自适应预报.基于青岛至新乡2007年3月和2012年3月最大可用频率观测数据,通过不同太阳活动期单步预报、不同步长短期预报和不同训练样本长度预报结果的统计,分析验证了方法的精确性、适应性和有效性.分析结果表明,采用Volterra级数自适应混沌预报方法进行超短期预测可以取得较好的预报结果,适用于不同太阳活动期;预测步长不大于1/12周期时,预报均方根误差均小于0.79MHz,与基于最大Lyapunov指数预报方法的结果对比表明,该方法在观测数据少和信道时变特性强等情形下仍具有较高精度且应用简便.其为高频频率预报技术的深入研究提供了基础.
In order to realize the adaptive prediction of maximum usable frequency in high-frequency communication, Volterra adaptive method is introduced. Based on the oblique sounding data of chain from Qingdao to Xinxiang in March 2007 and 2012, single-step prediction in different solar activ- ity years and short-term prediction of different steps and training samples length are conducted to validate accurateness, adaptability and validity of this method. Results indicate that the super short- term prediction adopting Volterra adaptive method has good agreement with oblique sounding data and this method is suitable for different solar activity periods. When the prediction step is not more than 1/12 period, RMSE is less than 0.79MHz. Comparison with prediction results of Lyapunov exponent method shows that Volterra adaptive method can gain upper precision in the situation of less data, time-varying channel etc., and the practical application is more convenient. The method provides a basis for in-depth study of high frequency prediction technology.