Description: 1）最大似然方法联合实现符号定时同步和载波同步仿真
2）泊松分布
3）贝叶斯估计
4）RANSAC方法-1) The maximum likelihood method of the joint realization of Symbol Timing and Carrier Synchronization in simulation 2) Poisson distribution 3) Bayesian estimation 4) RANSAC method Platform: |
Size: 4096 |
Author:平凡 |
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Description: ：LTE(Long Term Evolution，长期演进)系统中的小区初始搜索过程通过分别检测主同步信号(Primary Synchronization Signal，PSS)和辅同步信号(Secondary Synchronization Signal，SSS)来完成，搜
索结果包括小区组ID、符号定时、频偏估计、组内小区ID以及帧定时[1]。然而，若接收信号 1IDN 2IDN
中存在整数倍频偏，则由于时域的相位旋转，主同步信号将很难用传统的相关算法检测到。提出一种主同步信号与整数倍频偏联合检测的方法，即使存在整数倍频偏，也能得到正确的符号定时。辅同步信号采用的是非相干的差分相关检测[2]，仿真表明，与传统的匹配滤波算法相比，可以有效的对抗信道时延扩展和载波频偏，适用于高速场景下时分双工(Time Division Duplex，TDD)LTE系统的同步。-In LTE systems, the initial cell search process is completed by detecting the primary synchroniza-tion signal and the secondary synchronization signal. The searching results include cell ID group, symbol timing, frequency offset estimation, intra group cell ID and frame timing[1]. However, if integer frequency offset presents in the received signal, due to time-domain phase rotation, the primary synchronization signal will be difficult to detected using the conventional correlation algorithm. A new joint detection method for integer frequency offset and primary synchronization signal is proposed, which can get the correct symbol timing even if the presence of integer frequency offset. Secondary synchronization signal is processed using the differential non-coherent correlation detection method[2]. Simulations show that compared with the tradi-tional matched filtering algorithms, it can effectively combat the channel delay spread and carrier frequency offset and especially suitable for Platform: |
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Author:imc_lte |
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Description: One of the major challenges which prevents the coordinated multipoint (CoMP) communications concept from being widely deployed in new cellular systems is timing synchronization. In order to achieve the gains promised by CoMP systems, the user equipments’ (UEs) signals in uplink (UL) or the base stations’ (BSs) signals in downlink (DL) should be synchronized such that the time difference of arrivals (TDOAs) do not exceed the cyclic prefix (CP) length of the transmitted signals; Otherwise the system suffers from unavoidable integer time offsets. These offsets lead to asynchronous interference in terms of inter-carrier, inter-block and inter-symbol interference (ISI). This limits the percentage of area within a cell which can be covered by cooperation and imposes an upper bound on this area. In this paper, we investigate this problem in the UL and by using geometrical and semi-analytical approaches, we define this upper bound. Also, by characterizing an accurate mathematical model for the asynchronous interference in Rayleigh fading channels, we were be able to employ a standard MMSE-based receiver that mitigates this interference. Furthermore, a typical joint channel and delay estimation block is incorporated into the receiver to examine its performance with estimation errors. Platform: |
Size: 1869319 |
Author:ahamza |
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Search - Joint estimation of carrier and symbol timing