摘要
Autoregressive (AR) modeling is applied to data extrapolation of radio frequency (RF) echo signals, and Burg algorithm, which can be computed in small amount and lead to a stable prediction filter, is used to estimate the prediction parameters of AR modeling. The complex data samples are directly extrapolated to obtain the extrapolated echo data in the frequency domain. The small rotating angle data extrapolation and the large rotating angular data extrapolation are considered separately in azimuth domain. The method of data extrapolation for the small rotating angle is the same as that in frequency domain, while the amplitude samples of large rotating angle echo data are extrapolated to obtain extrapolated echo amplitude, and the complex data of large rotating angle echo samples are extrapolated to get the extrapolated echo phase respectively. The calculation results show that the extrapolated echo data obtained by the above mentioned methods are accurate.
用自回归(AR)模型对散射场数据进行外推,并用计算量小、可获得稳定预测滤波器的伯格(Burg)算法估计AR模型的预测参数。对于频域,直接对散射场回波复数据进行外推,可获得外推散射场。对于方位域,分两种情况:在小转角条件下,用与频域相同的方法获得外推散射场;在大转角条件下,用散射场回波数据的幅度进行外推,获得外推散射场的幅度,用散射场回波复数据进行外推,再提取外推散射场的相位。算例结果表明,用本文的外推方法,取得了较好的外推效果。
