Methods of Subframe Number Detection and Timing Offset Estimation of Non-signaling Test Based on LTE

Along with the popularization of 4G communication technology, non-signaling test technology of mobile terminals becomes increasingly important. Since it eliminates the process of signaling interaction and uplink synchronization, the measuring equipment must primarily find the starting position of a subframe in the received data to extract all data of this subframe and acquire the subframe number before performing a test. According to the connection between demodulation reference signal (DMRS) and subframe number, in this paper, we propose two blind detection methods of which the first one is the bimodal interval detection method that only exploits DMRS and the other one is the position contrastive method which exploits both DMRS and cyclic prefix (CP). Furthermore, the corresponding simulation model is established and evaluated respectively. Finally, a joint method combining the advantages of these two methods is suggested. Both real test and simulation prove the joint method is of good performance.