Abstract: As the basis of the tracking algor ithm, an echo model is the key to radar altimeter design. To modify thewell known BROWN model, a new altimeter echo model and its applications are provided, which is called universalalt imeter echo model. It pr evails over the former both in precision and in application scope. This new model can satisfy various requirements and will play an important role in the design of altimeter tracking algorithms.

Key words: altimeter, echo model, universality