People spend most of their life time in indoor environments and in all of these environments, Location Service Providers (LSPs) improve users’ navigation. Preserving privacy in Location Based Services (LBSs) is vital for indoor LBSs and fingerprinting based indoor localization method is an emerging technique in indoor localization. In such systems, LSP may be curious and untrusted. Therefore, it is preferred that user estimates its location by using a Partial Radio Map (PRM) which is achieved by LSP, anonymously. In this paper, a privacy preserving method that uses Bloom filter for preserving anonymity and creating PRM during localization process, is proposed. In this method, LSP cannot recognize user identity, which is anonymized by the anonymizer. The proposed method has lower computational complexity compared with methods that use encryption or clustering concepts. The proposed method also has higher accuracy in localization compared with those that use Bloom filter with one random selected AP. Then, in order to decrease the complexity and to increase the accuracy at the same time, we introduce a method that expands the radio map by authenticated users, without compromising their privacy. We also enhance the performance of this method, using Hilbert curve for preserving the ambiguity of users’ location. After verifying the user’s data, LSP sends a certificate to the authenticated users. This certificate can increase the priority of users in LBS requests. Simulation results and measurements show that the proposed method on average improves the localization accuracy up to 16% compared with existing location privacy methods.

人们将一生的大部分时间都花在室内环境中，而在所有这些环境中，位置服务提供商（LSP）都会改善用户的导航。在基于位置的服务（LBS）中保护隐私对于室内LBS至关重要，基于指纹的室内定位方法是室内定位中的一种新兴技术。在这样的系统中，LSP可能是好奇的并且不受信任。因此，优选地，用户通过使用由LSP匿名实现的局部无线电图（PRM）来估计其位置。本文提出了一种隐私保护方法，该方法使用布隆过滤器来保留匿名性并在本地化过程中创建PRM。在这种方法中，LSP无法识别由匿名器匿名的用户身份。与使用加密或聚类概念的方法相比，所提出的方法具有较低的计算复杂度。与使用带有一个随机选择的AP的Bloom滤波器的方法相比，该方法的定位精度更高。然后，为了降低复杂度并同时提高准确性，我们引入了一种方法，该方法可以在不损害用户隐私的前提下，对经过身份验证的用户扩展无线电地图。我们还使用Hilbert曲线保留了用户位置的歧义性，从而提高了该方法的性能。验证用户数据后，LSP将证书发送给已认证的用户。该证书可以增加LBS请求中用户的优先级。