Terscat - a Model for Prediction of Terrain Scattered Interference in Microwave Cmmunication

Prediction of multipath delay profiles in mountainous terrain

“…Each cluster was identified with the particular mountain slope for which the indirect path length from transmitter via mountain slope to receiver corresponds with the average delay of the cluster. We wish to compare the values of in the propagation model (4) and (5) with estimates obtained from the measured power in each cluster. This measured power is determined by summing the values of over the range of delays of the cluster.…”

“…Models of the propagation loss of a delayed path scattered from mountainous terrain have been presented in [4], [5], [10]- [12], [17], and [23] based on the bistatic radar equation (1) where wavelength; scattering cross section of the target; transmitted and received powers; transmitter/scatterer, scatterer/receiver, and transmitter/receiver path lengths. Furthermore, with is the relative delay between direct and delayed paths and is a time reference.…”

“…In (3), we select only those elements in a range cell for which is constant to within the distance resolution , so that is the weight of the impulse response at time delay relative to the direct path. Thus the integral becomes the sum (4) where is the normalized scattering cross section of the patch of area with area , and the patches are chosen such that . By performing the integral over different range cells, the squared magnitude of the channel impulse response is obtained as (5) where the are local mean or spatial average values.…”

“…For large distributed targets such as mountain slopes (in contrast with point targets such as isolated buildings), it is reasonable to assume that the differences in within the area of integration are smoothed out [4]. Thus a much coarser grid of areas which include complete major mountain slopes in one or two elements can be used.…”

Interference from mobile satellite systems through terrain scattering

“…Such mechanism has been proven to be dominant over the direct coupling for interference between terrestrial microwave transmission systems [2][3][4][5][6][7] and is also suspected to surpass the Shapira direct coupling in this case in many scenarios. Mitigation of this interference by adaptive canceling techniques may prove impossible, as the interference is collected over a wide angular and delay spread, and may involve more than one satellite.…”