The Research On Detection Algorithm On Downlink Control Channel In Lte

In order to deal with the challenge of wireless access technology, the international standardization organization3GPP launched standardization work of LTE technology at the end of2004. As a definite Fourth Generation (4G) wireless broadband technology, Long Term Evolution (LTE) which based on Multiple Input Multiple output (MIMO) technology, adopts Orthogonal Frequency Division Multiple Access (OFDMA) technology in the downlink and Single Carrier Frequency division Multiple Access (SC-FDMA) in the uplink direction. In addition, many adaptation techniques such as fast link adaptation, Hybrid ARQ (HARQ), fully dynamic packet scheduling and so on make it possible to efficiently exploit the time-frequency resources and provide significant LTE gains at cell and user level.Closely related to resource allocation and control information scheduling for system, the reception of Physical Downlink Control Channel (PDCCH) plays a key role on the reaction speed of the whole system. In order to improve the performance of systemand reduce the delay, the paper deeply researches how to optimize the blind detection for PDCCH.In this paper, feedback scheme which based on the overlap of different search spaces is proposed at first and this scheme makes use of the results in previous step to optimize remained search space. The relation between the scope of SNR and CCE aggregation level can be deduced from the relationship between CCE aggregation level and coding efficiency, on this basis the paper puts forward SNR scheme in which UE directly skip the CCE aggregation level that cannot be decoded correctly to degrade the number of blind detection. For consideration of the two schemes above, the paper finally comes up with a integrated scheme which brings the advantsge of the two schemes above together, thereby decrease the number of blind detection.In order to validate the performance of proposed schemes for blind detection, we design and set up simulation platform, mainly simulate the blind detection of common search space and UE specific search space. Without bringing extra singaling over the air, feedback scheme decrease the number of blind detection by18%and in SNR scheme the decrease percentsge is43%, in the meanwhile the number in integrated scheme is57%.