中文摘要：

针对无线通信系统中利用信道特征提取密钥效率较低的问题，提出了一种利用正交频分复用（OFDM）系统无线信道相位响应的密钥提取方案，该方案首先利用相位随机化的信号对信道相位响应进行探测，并且随机选择一个合法节点对探测得到的信道相位进行量化生成初始密钥；其次，将初始密钥进行映射和预均衡处理后发送给对方节点，实现初始密钥的安全分发；最后，合法双方通过信息协商和保密增强获得安全密钥。该方案充分利用了无线信道相位响应的随机性和互易性，只需要一个合法节点来量化产生初始密钥，减少了量化处理，提升了密钥提取性能，同时由于信道相位响应对于收发端之间的距离十分敏感，保证了该方案的安全性。仿真结果表明当信噪比为 10d B 时，与已有的基于信道相位和信道幅度的密钥提取方案相比，所提方案的密钥容量分别增加 34%和 1.7 倍，密钥不一致率分别降低 37%和 63%，密钥产生速率分别提高 6.6%和 17%，同时所提方案生成的密钥通过了 NIST 随机性测试。

英文摘要：

Coal-fired boiler is a main exhaust source of greenhouse gas CO2 and air pollutants. Therefore, enhancing the research and application of technologies for energy saving and emission reduction of coal-fired boiler is very important to CO2 reduction and air quality improvement. Recent technologies and methods for energy saving and emission reduction for coal-fired utility boiler and industrial boiler are analyzed and reviewed respectively. These technologies and methods include promoting strict policy for energy saving and emission reduction, using large capacity supercritical pressure coal-fired power generation unit, using IGCC, developing coal based co-production system and CO2 capture technique, reforming industrial boiler, and using advanced cleaning apparatus of boiler exhausted gas. The research and development of the technologies are finally anticipated and suggested.