  This paper describes a high-fidelity sonar model and a simulation environment
that implements the model. The model and simulation environment have been
developed to aid in the design of a forward looking sonar for autonomous
underwater vehicles (AUVs). The simulator achieves real-time visualization
through ray tracing and approximation. The simulator facilitates the assessment
of sonar design choices, such as beam pattern and beam location, and assessment
of obstacle detection and tracking algorithms. An obstacle detection model is
proposed for which the null hypothesis is estimated from the environmental
model. Sonar data is generated from the simulator and compared to the expected
results from the detection model demonstrating the benefits and limitations of
the proposed approach.
