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