【摘要】 为改进第3代移动通信标准WCDMA中基于时分复用导频符号辅助的信道估计问题,将分形理论引入多径衰落信道的描述.在多径衰落的分数布朗运动模型的基础上,提出一种利用两个连续时隙的导频符号估计出的信道参数进行分形内插的信道估计方法.与传统方法相比,该算法充分考虑了在高速运动及深度衰落的情况下信道参数快速变化的因素,使系统能更准确地估计衰落信道的参数,其性能在高速信道下优于原有算法,且可以自适应地跟踪信道衰落的变化.仿真结果验证了采用该方法的Rake接收机性能.与传统的随机模型相比,新的分形信道模型能更好地刻画出多径衰落的行为.更多还原

【Abstract】 The fractal theory is applied to the description of multipath fading channels in order to improve the channel estimation using time multiplexed pilot symbols in wideband code division multiple access (WCDMA) systems. Based on the fractional Brownian motion model of multipath fading, a novel channel estimation scheme using fractal interpolation between the instantaneous channel estimation of two successive slots is presented. Because the fast varying effect of channel parameters in fast terminal moving cases is considered, the proposed method can estimate the channel parameters more accurately than that of the existing schemes and selfadaptively track the channel changes in different terminal moving speeds. Computer simulations demonstrate the performance of the Rake combiner is improved notably. Additionally,the results show that the fractal model can describe multipath fading more effectively compared to the conventional statistical models. 更多还原