The concept of Delay/Doppler Radar Altimeter (DDA) was proposed by R.K Raney<sup></sup> to improve the spatial resolution in the along-track direction, for rougher surfaces more irregular than open oceans. DDA also has many new advantages when it is used for open oceans, such as stronger response, being less sensitive to off-nadir angle errors, and being more sensitive to significant wave height (SWH) than Conventional Radar Altimeters (CRA). These new features and advantages will be validated by simulations in this paper.
Echo tracking is always an important part in the design of radar altimeter, which is required in many ways. But above all, the essential requirement for the tracking is to avoid track losing, furthermore, the tracking precision and algorithm operation scale also are need to be optimized. So all the factors mentioned above have to be considered comprehensively. Till today, various tracking algorithms have been developed for different applications, but the common shortage of them is that they depend on some specific target modes strongly, which leads to poor adaptability to different targets and easily losing tracking. As to this problem, OCOG will be introduced in this paper, which is a good robust tracking algorithm and will be applied into a new type of satellite altimeter, tridimensional imaging radar altimeter, which will be applied in complex environments including sea, seaice and coast.