中文摘要：

为保护稀疏环境下的用户身份和位置信息，提出一种基于位置服务（LBS）的隐私保护方法，通过确定访问的LBS服务是否为匿名服务决定增加虚拟用户还是虚拟位置。根据空间区域的时延特点模拟生成真实用户位置信息及其分布，保证虚拟信息的拟真性。通过增加虚拟用户信息或位置信息及其关联映射复杂度，实现用户匿名性。实验结果表明，与随机生成虚拟信息的隐私保护方法相比，该方法生成的虚拟信息更符合真实场景，具有更好的隐私保护效果。

英文摘要：

In order to protect the user＇ s identity and location information in sparse environment, this paper proposes a privacy-preserving method of Location Based Service（LBS）, by determining whether or not the accessed LBS service is anonymous to add the virtual user or virtual location. According to the characteristics of time delay, the real user location information and distribution are simulated to ensure the fidelity of virtual information. Virtual user information or location information and their relevance mapping complexity are added to achieve user anonymity. Experimental results show that compared with privacy-preserving method of randomly generated virtual information, the virtual information generated by this method is more consistent with the real scene and has better privacy-preserving effect.