基于最小容忍剩余误差松弛变量的频偏补偿

Frequency Offset Compensation Based on the Minimum Tolerated Residual Error Slack Variables

分布式蜂窝网络中支持多个射频拉远单元(radio remote unit,RRU)和多个用户设备(user equipment,UE)同时参与协作传输,但是高速运动和其他原因会导致RRU-UE间存在多普勒频偏和时延,而且由于各个RRU-UE支路之间的时频偏不均衡性导致补偿困难。创新性地在补偿过程中加入松弛变量,在满足系统最大容忍剩余频偏约束的前提下求出次优的频偏补偿值。实验结果表明所提出的方法在很好地补偿UE端时频偏的情况下也能够补偿RRU端的频率偏移且效果理想,基于此还可为多点-多用户协作组合优选提供一种良好的筛选判据。

Distributed cellular network supports multiple radio remote unit （RRU） and user equipment （UE） are participated in cooperative transmission, but the high speed movement and other reasons cause the Doppler shift and delay between RRU and UE, and the imbalance between each RRU-UE branch in time and frequency offset made compensation difficult. Innovatively added slack variables to the compensation process, then in the precondi- tion of satisfying the maximum tolerance of the residual frequency offset constraint to found the suboptimum frequen- cy offset compensation value. Experiment results indicate that the method could compensate frequency offsets on UE and RRU, based on this can also provide a screening criterion for the optimum multi-point muhi-user collaboration combination.