High Frequency (HF) oceanographic radars can measure currents, waves and winds at the surface of the coastal ocean to ranges of up to 200km from the coast. They have many potential applications e.g. for search and rescue, port and harbour management, coastal erosion modelling and management, marine renewables, offshore oil, gas and wind farm operations, ship routing, leisure boating, tsunami detection, water quality and coastal development, marine ecology. German and US radars are found around many of the coasts of the world providing surface current measurements for many of these applications. The UK has an under-exploited world class technology base in this field, this project could provide the impetus to grow UK business and turn this knowledge into a source of export revenue. This project is part of our plan to develop the next generation of these radars that will be both cheaper, and hence more competitive in this small niche market, and will provide more reliable wave measurements and thus meet the needs of marine renewable and offshore oil and gas installations, Met Offices and/or other government organisations who provide routine wave forecasts for shipping and leisure activities. This project focuses mainly on the reliability of the wave measurements with research on a new idea to exploit the fact that different radar operating frequencies have different responses to wave conditions.