The causes and solutions of blind area in HF communication are analyzed at first. The typical vehicle mounted halfloop antenna and its transformation called whip antenna are used for simulation to analyze the parameters such as impedance, maximum elevation angle, pattern and maximum gain with different frequencies. Then the optimum working frequency bands of halfloop antenna is obtained for NVIS communication. Finally, the NVIS communication abilities of vehicle mounted halfloop HF antenna are verified by actual measurements with frequencies, distances and effects of communication.