Models ocean surface reflection loss using Beckmann-Spizzichino model.
Jones et. al. has shown that this model can be broken into high and low frequency components. The high frequency component is given by:
where ,
= wind speed (m/sec), and
is limited to a 0.99 value. Note that the high frequency component is frequency independent. The low frequency component is given by:
where = signal frequency (Hz). Note that the low frequency component is grazing angle independent. The total reflection loss is the sum of these two terms in dB.
reflect_loss_beckmann | ( | double | wind_speed | ) | [inline] |
Initializes ocean surface reflection loss using using Beckmann-Spizzichino model.
wind_speed | Wind_speed used to develop rough seas (m/s). |
void reflect_loss | ( | const wposition1 & | location, | |
const seq_vector & | frequencies, | |||
double | angle, | |||
vector< double > * | amplitude, | |||
vector< double > * | phase = NULL | |||
) | [virtual] |
Computes the broadband reflection loss and phase change.
location | Location at which to compute reflection loss. | |
frequencies | Frequencies over which to compute loss. (Hz). | |
angle | Grazing angle relative to the interface (radians). | |
amplitude | Change in ray intensity in dB (output). | |
phase | Change in ray phase in radians (output). Hard-coded to a value of PI for this model. Phase change not computed if this is NULL. |
Implements reflect_loss_model.
const double _wind_speed [private] |
Wind speed (m/sec).