Research On DRX Algorithm Based On LTE/LTE-advanced System

As one of the most important technology to optimize the energy efficiency in theMAC layer, improve the utilization ratio of energy in the LTE communicationsystem,. DRX technology (Discontinuous Reception, DRX) has become anirreplaceable important technology adopted by LTE/LTE-A system. The basic idea ofDRX is UE to monitor PDCCH channel control information in the active period, thusfor data transmission; In stage of sleeping time halted monitor the PDCCH channel,stop data reception at the same time, to reduce the UE power consumption, achievethe goal of saving energy reducing in order to decrease system power consumptionBased on the LTE/LTE-A system, this paper studies the technique ofdiscontinuous receiving under the condition of satisfying users business time delay,packet loss rate and quality of service (QoS) how to make the DRX mechanism foroptimum performance.This paper mainly engaged in the following several aspects work:The firstly,for3GPP TS36serial protocol makes a deep study and research,including the physical layer and MAC layer protocol36.211and36.212protocol36.213and36.321,in the LTE system with the framework made in-depth study,especially to the DRX behavior related in eNB side conducted in-depth study. withthe understanding of all above, we set the LTE system simulation platform of DRXsimulation module.The secondly,on the analyzed of The DRX function of the LTE system function,on the basis of MARKOV modeling for the DRX mechanism of LTE system,according to the MARKOV state transition analysis system in the relationshipbetween the number of users and packet delay, packet delay is deduced with the DRXrelations among energy saving. Simulation the three kinds of DRX extension plan forLTE-A system. summarized the advantages and disadvantages of each scheme.The third, with the analyzed and study of the fixed DRX cycle and dynamicconfiguration DRX parameters of which named Multiple-Threshold DRX,and makeimprovements for the disadvantage of in system user count increased consumptionwill increase greatly, which brings to the user data packets of large time delay,according to different business users configuration different DRX parameters, theuser depending on the type of business operation of the corresponding parameters. Simulation results show that the improved algorithm increased the number of users inthe system, the improved algorithm can well reduce the user delay, effectively reducethe system cost.The fourth, On the basis of analysis of MT-DRX algorithm and CDA-DRXalgorithm in the LTE-A system, We optimized the CDA-DRX algorithm based onuser’s QoS. First of all, Let all UE DRX cycle in the system configured to integertimes, in order to reduce the unnecessary wake up due to competition for resourcesbetween UE; Second through to choose DRX-Inactivity timer length to calculate thecalculation of UE packet loss rate, to improve the channel condition is not stable andwith unexpected users packet delay; The simulation results show that the improvedalgorithm can effectively improve the user’s QoS, reduce the delay for the user.