基于连接层的天波雷达高度估计算法研究

摘要

天波雷达具有探测距离远、覆盖范围大的优点，在对远距离目标探测方面具有显著优势，受到广泛关注。目前天波雷达主要是通过微多径模型来估计目标高度信息。其中，基于匹配场处理算法得到了较好的目标高度信息，但该算法忽略了电离层的连接层。该文注意到忽略连接层的电离层模型是不连续的，而实际的电子浓度是连续变化的，因此不考虑连接层的电离层模型与实际情况不符，会影响目标高度估计的性能。基于该考虑，提出了基于电离层连接层模型的改进的天波雷达高度估计算法。该方法首先建立了与实际相符的含连接层的电离层模型，使其电子浓度连续平滑变化，在此模型上进行高度估计，得到更好的效果。仿真结果表明，与已有方法相比，该文的高度估计精度更高，收敛速度更快，在第6个驻留周期高度估计误差就可收敛至1 km 以内，平均误差为715 m，而有关文献中的高度估计误差在第26个驻留周期才可收敛至1 km，平均误差为1456 m。%Skywave radar has advantages such as a long detection range and a large coverage and it has attrac-ted great attention because of its significant advantage in detecting distant target.Skywave radar obtains target's alti-tude mainly through micro-multipath model.Matched-field-processing algorithm can obtain more accurate altitude of target,but the algorithm ignores the joining layer of the ionosphere.The ionosphere model is not continuous if igno-ring the joining layer,but the actual electron density changes continuously.So the ionosphere model of ignoring the joining layer does not match with the actual situation and it may make the performance of altitude estimation worse. Based on this consideration,an improved skywave radar altitude estimation algorithm based on joining layer model is proposed.The algorithm establishes the ionosphere model containing joining layer to make the electron density change continuously and smoothly,which matches the real scenario.Based on this model,better performance of altitude estimation can be acquired.Simulation shows that a better altitude estimation accuracy and a faster convergence rate can be obtained with the proposed algorithm.