Aiming at the problems of low gain, low efficiency in low frequency band and warping pattern in high frequency band of the existing HF broadband whip antenna, this paper introduces frequency reconfigurable antenna technology and radiation blades loading technology to redesign whip structure, loading and matching network in different bands, and designs a kind of frequency-reconfigurable whip antenna with improved gain and efficiency. The whip body structure, loading and matching network structure of the antenna in each band are optimized, and the on-off control is carried out through the radio frequency switch according to the actual needs. The results show that the standing wave ratio of the proposed antenna is all less than 3, the average value is 2.32; the gain is all greater than -2dB, the average value is 3.63dB; the total efficiency is all over 20%, the average value is 72.77%, and the pattern keeps horizontal omnidirectional in the whole short wave band without upward warping phenomenon.INDEX TERMS Frequency-reconfigurable technology, radiation blades loading, broadband antenna, lumped loading, matching network, grasshopper optimization algorithm.