To solve the problem that the fingerprint database updating requires a huge amount of time and laboring effort, a new Received Signal Strength (RSS) estimation method was proposed in WiFi environment. Part of remeasured RSS fingerprints was used to fit RSS surface by the radial basis function interpolation, the RSSs of the unknown reference points were estimated nearby the known reference points, and then the whole fingerprint database was update. The extensive experiments prove that only a quarter of the reference points need to be remeasured, the cumulative error probability will be similar with the actual database within the positioning error of 2 m, and thus the method guarantees the satisfactory positioning accuracy.

To deal with high computing complexity and bad anti-CFO (anti-Carrier Frequency Offset) performance of conventional time synchronization algorithms for Time Division Long Term Evolution (TD-LTE) system, an improved algorithm based on Secondary Synchronization Signal (SSS) conjugate-symmetric in time domain was proposed in this paper. For the algorithm, SSS location was estimated as the peak of cross-correlation of received signal and its time reversal. And by combining SSS location with the detection of cell group ID, CP (Cyclic Prefix) type could also be judged. Analysis and simulation results demonstrate that the improved algorithm has low computing complexity, good performs on anti-CFO and better reliability compared with normal methods, especially, it also has good performs in multi-path channels. By applying to the third party TD-LTE UE detecting system, the algorithm is proved to be effective and feasible.