A new signal model for a wideband synthetic aperture imaging sensor

A new signal model was developed to replace the traditional one that is based on the go-stop-go assumptions (the go-stop-go model for short) for a wideband synthetic aperture imaging sensor. Using the new model, we traced the time line of the transmitted signal with a given pulse width, round trip time delay of the signal between the sensor and target, and receiving signal with a fixed pulse duration. The spatial displacement of the senor along the time line was calculated. Then, we obtained the two-dimensional spectrum of an individual target and utilized the two-dimensional joint stationary phase method to solve the spectrum. Incorporating the spectrum with available imaging algorithms, we were able to focus targets in a scene. The performance of the model was investigated by analyzing simulated wideband synthetic aperture radar and synthetic aperture sonar data. In the simulations, the imaging algorithms with the new or go-stop-go model were implemented and outputs compared. Results were very promising.