ASA 124th Meeting New Orleans 1992 October

2pUW4. High-frequency scattering in the Arctic.

Gary Steven Sammelmann

Coastal Systems Station, Panama City, FL 32407-5000

There currently exists no high-frequency model of propagation in the Arctic. This article describes a simple, fast model for computing high-frequency propagation in the Arctic. This model is a one-parameter model of scattering in the Arctic, where the free parameter of this model is the average rms slope of the small-scale surface roughness of the ice canopy. This model couples ray theory to a scattering strength formalism of scattering from a rough surface. This coupling is achieved by associating an effective area of ensonification with each ray trajectory from the source to the receiver. The average intensity at the receiver is obtained by performing an incoherent summation over all possible ray trajectories from the source to the receiver, including nonspecularly scattered rays. A comparison between model predictions and experimental measurements of forward scattering is made. The model predicts the overall shape and amplitude of the scattered signal within 5 dB depending upon the range of the source to the receiver.