Simulation of the correlation velocity log using a computer based acoustic model

The Correlation Velocity Log (CVL) can be used on both surface and underwater vessels to measure the velocity relative to the seabed. The CVL has distinct advantages over rival systems, such as inertial navigation and Doppler logs, at low speeds, making it especially suitable for use on autonomous underwater vehicles (AUVs). The aim of this project is to develop a new CVL which incorporates a number of innovative components that will lead to a significant increase in the system accuracy. The project includes the development of a software simulator and a hardware technology demonstrator. This paper describes the simulation part of the project. A two level simulation strategy is employed to investigate the detailed short time scale behaviour independently of the performance over a longer time scale. The detailed model is used to improve the understanding of the effect of variations in the physical environment and of transducer characteristics. A second model is used to study the effect of random and systematic errors over a long time scale and to test different operating and processing strategies. A fully functioning prototype of the system is being developed in parallel with the simulator.