Two-Ray Model

This propagation model applies to short-range and low antenna heights for the transmitter and the receiver antennas. The situation may arise where the receiving antenna may experience a destructive ground reflection besides the LOS transmission.

STK computes the Total Propagation Loss using Complex signal values and then removes the free space loss. The two-ray component and the free space loss values are reported independently under the Free Space Loss and Urban Terres Loss elements of the access Link Information data provider.

The total propagation loss (free space and two-ray destructive/constructive signal loss/gain) is computed by adding the direct ray signal complex value and the reflected ray signal complex value. The complex (real/imagery) addition of the two signals determines the total loss/gain. The free space loss component is removed to report Two-Ray loss separately.

Note that this model is intended for low transmitter/receiver altitudes and short-range situations. It is best practice to use the model under these situations. If these conditions are not satisfied, the model accuracy may be compromised.