Page 136 - Fundamentals of Radar Signal Processing

Source: Adapted from Currie (2010).

TABLE 2.6 GTRI Land Clutter Model Parameters for X Band

0
Models of a similar spirit exist for sea clutter σ . Important parameters for
sea clutter reflectivity in addition to frequency, grazing angle, and polarization
include wind speed and direction relative to the radar boresight, wave height,
and multipath. Details of one representative model developed at GTRI are given
in Currie (2010).

2.3.2 Signal-to-Clutter Ratio

In many scenarios, the dominant interference is not noise, but clutter.
Consequently, the signal-to-clutter ratio (SCR) is often of more importance
than the signal-to-noise ratio (SNR). The SCR is easily obtained as the ratio of
the received target power, given by Eq. (2.11) to the received clutter power,
given by Eq. (2.25), (2.30), or (2.32) for the volume clutter, beam-limited area
clutter, and pulse-limited area clutter cases, respectively. The resulting
equations are

(2.66)

In each case, such system parameters as the transmitted power and the
antenna gain cancel out. This occurs because both the clutter and target signals
are echoes of the radar pulse; increasing power or antenna gain increases the

strength of both types of echoes equally. Thus, the SCR just becomes the ratio of
the target RCS to the total RCS of the contributing clutter.

2.3.3 Temporal and Spatial Correlation of Clutter
Clutter decorrelation in time is induced by internal motion for clutter, such as