文件名称:www
介绍说明--下载内容均来自于网络,请自行研究使用
使用维纳分布进行瞬时频率估计用来校正电离层非线性相位污染带来的频带展宽-High-frequency (HF) sky-wave radar
signals propagate to and from the target by means
of the ionosphere. The difficulty in obtaining very
narrow beamwidths at HF, and the long ranges
involved, mean that the signal backscattered from
the ground is often several orders of magnitude
greater than the target echo. To resolve the target,
coherent signal processing techniques are necessary,
detecting the target echo by virtue of the
Doppler shift caused by the target’s radial velocity.
Unfortunately, movement of the ionospheric
layer by which the radar signal has propagated
often causes the clutter spectrum and target to
spread in the frequency domain, rendering
extended coherent integration pointless. The
movement of the ionosphere can be regarded as
producing frequency modulation of the radar
signal, and thus if this modulation can be estimated
the radar signal may be corrected for the ionospheric
contamination. A technique using the
complex argument of the first-order mo
signals propagate to and from the target by means
of the ionosphere. The difficulty in obtaining very
narrow beamwidths at HF, and the long ranges
involved, mean that the signal backscattered from
the ground is often several orders of magnitude
greater than the target echo. To resolve the target,
coherent signal processing techniques are necessary,
detecting the target echo by virtue of the
Doppler shift caused by the target’s radial velocity.
Unfortunately, movement of the ionospheric
layer by which the radar signal has propagated
often causes the clutter spectrum and target to
spread in the frequency domain, rendering
extended coherent integration pointless. The
movement of the ionosphere can be regarded as
producing frequency modulation of the radar
signal, and thus if this modulation can be estimated
the radar signal may be corrected for the ionospheric
contamination. A technique using the
complex argument of the first-order mo
(系统自动生成,下载前可以参看下载内容)
下载文件列表
Use of theWigner-Ville distribution to compensate for ionospheric layer move.pdf