CAJ | 학술논문

针对多天线信道频偏参数的随机时变特点，建立参数化的观测模型，根据时变参数估计的克拉美-罗下界求取原理，在非线性的观测模型和序贯的观测值下，利用参数真值推导频偏估计的克拉美-罗下界。由于特征参数的真值不可知，因此将观测模型在估计值处进行二阶泰勒级数展开，通过参数估计值获得频偏参数估计的近似下界。仿真结果表明，基于参数真值和估计值的频偏估计下界具有渐近收敛性，且随信噪比和观测值个数的增加均能达到稳态。
침대다천선신도빈편삼수적수궤시변특점，건립삼수화적관측모형，근거시변삼수고계적극랍미-라하계구취원리，재비선성적관측모형화서관적관측치하，이용삼수진치추도빈편고계적극랍미-라하계。유우특정삼수적진치불가지，인차장관측모형재고계치처진행이계태륵급수전개，통과삼수고계치획득빈편삼수고계적근사하계。방진결과표명，기우삼수진치화고계치적빈편고계하계구유점근수렴성，차수신조비화관측치개수적증가균능체도은태。
According to the characteristics of random time-varying frequency offsets parameters of multiple antenna channel, this paper establishes the parametric observation model. It depends on time-varying estimation Cramer-Rao Lower Bound(CRLB) calculation principal, derives the CRLB of frequency offsets characteristics parameters under nonlinear observation model and sequential observations. The value of characteristics parameters is unknown, the observation equation is linearized at estimated values by using Taylor series expansion and then it gets the approximate CRLB of frequency offsets. Simulation results show that the method can achieve good asymptotic convergence of varying parameters’ CRLB whether the true value of the parameters are known or not. The two estimation lower bounds can reach steady state with the increment of signal to noise ratio and the number of observation value.