| The basic principle of adaptive modulation and coded(AMC) technology is to achieve the best balance between the data transfer rate and the bit error rate within the system restriction.In the conditions of the given average bit error rate,the control of the instantaneous bit error rate is less than a given bit error rate bound.Based on channel gain,the sending end is to change the coding rate and modulation constellation size to adjust the transmission data rate.Therefore,with this AMC scheme High Speed Packet Access(HSPA) system can arrive the maximum system throughput.All the research work here is based on the HSPA protocols released by 3GPP.Given AMC algorithm and system model in the Multiple Input and Multiple Output(MIMO) system,simulated average throughput and average bit error rate of the adaptive MIMO system.Simulation results show that compared with the Single Input Single Output(SISO) system,multi-antenna adaptive technology with Orthogonal Space Time Block Code(O-STBC) not only increases the average throughput of the system,but also effectively reduces the channel fading on the system performance.Firstly,research background of HSPA is illustrated.The process and commercial deployment of HSPA is briefly summarized.Compared with the 3GPP Release 99,the new HSPA transmission channel and physical channel and the corresponding frame format are introduced.Meanwhile,several key technolegies such as AMC,Hybrid Automatic Repeat Request(HARQ),Fast Check Scheduling(FCS) and MIMO are introduced.The key part of this thesis builds the flow chart of transceiver and receiver of the entire system and gives the HSPA baseband physical layer simulation of link analysis.Based on signal to noise ratio threshold switching algorithm is proposed.In the condition of ideal channel estimation,the performance gain of HSPA is simulated in adaptive MIMO diversity system.Then,consideration non-ideal channel estimation and delay system,the paper highlights the optimal threshold adjustment algorithm of the AMC,and simulates out system performance.Finally, through the summarization of the whole work, some potential directions for further study are discussed. |
