Research On3GPP LTE Uplink Random Access

In order to meet the needs of new service and the requirements of high transmission rate of mobile terminal, the third generation partnership project(3GPP) initialized technology standardization work named Long Term Evolution(LTE) by the end of2004. Random access technology is a key technology in a communication system, and random access is a critical step. Random access is the only way to access network for termnals, and its performance is directly related to the merits of the entire system.The paper studied LTE uplink random access, and the main work is reflected in:(1)I analysed the role of CP and GT in the time domain structure and the scene which several formats can apply in, including frequency domain structure of the preamble sequence and resource mapping. On this basis I gived a detailed analysis of generation for random access preamble sequence, in particular, I focused on the analysis of the cyclic shift values in the limit mode and the process of baseband signal.(2)I estblished a transmitter model in random access. According to the model, I presented traditional receiver algorithm design in random access. Based on the analysis of computation I presented improvement from two points in order to reduce the computation.(3)I used MATLAB software to build link simulation platform and program for the transmission and reception. Accordingly I used MATLAB to verify the performance of the algorithm after improvement in random access. Simulation results showed that the detection performance of algorithm after improvement can meet the protocol. On the premise of this the computation burden of algorithm after improvement can reduce to ten percents even one percent of the algorithm before improvement in an operation cycle. Accordingly it can improve the operational effiency.