Abstract: In order to efficiently transmit the picture data in the air traffic control system，an improved image coding algorithm，which is based on Embedded Zero-tree Wavelet（EZW），is presented.At first，the lowest frequency sub-band is coded without loss.Then，based on the human visual system，different sub-bands at the same level based on different perceptual weights are merged.In the end，Huffman coding is used for EZW result.The experiment result shows that this method is better than the original EZW algorithm.

Key words: wavelet coefficient, Embedded Zero-tree Wavelet（EZW）, Human Visual System（HVS）, Huffman coding, air traffic control system

摘要： 为了在空管系统中高效率传输景象数据，在嵌入式零树小波图像编码算法（EZW）的基础上进行了按步骤的整体优化，对低频子带进行无损编码，对同一级的不同子带根据人眼视觉特性进行加权合并，用Huffman编码对符号流进行二次编码，实验结果表明，该方法要优于传统的EZW算法。

关键词: 小波系数, 嵌入式零树小波图像编码算法（EZW）, 人类视觉特性（HVS）, Huffman编码, 空管系统