Research On Random Access Technology Of LTE Uplink

As services of UE is face to principles of IP optimization in the future mobile communication system,random access should not only provide timing synchronization,but also payload part of message bits,meanwhile,LTE has strict requirement of short time delay.So,how to save resoures of time and frequency are the points of design of random access and the communicationThis thesis mainly analyses the proceduce of non-synchronized random access. A random access design of the message bits are transmitted implicitly is proposed. The design includes three part:the structure of preamble,emission and receive method.This design can improve system effienciency and reduce the access delay by the way of preamble implicating little message bites.The time-domin cycle shift between signature sequence and signature sequence which implicating message bits is integral multiple of the cycle shift step.The message is implicited in the integral multiple location.The detetion of this special kind of preamble is almost the same as the traditional's,so the design doesn't led to extra complication.At last,in order to test the rationality and feasibility of the system design,the performance of modes in non-synchronized random access is simulated in Matlab.As simulation result shows,the proposed design modes in non-synchronized random access meet the demands of 3GPP LTE and support " one step "procedure.