An Improved Electronic Image Motion Compensation (IMC) Method of Aerial Full-Frame-Type Area Array CCD Camera Based on the CCD Multiphase Structure and Hardware Implementation

Abstract

In this paper, the performance of the electronic conventional image motion compensation (IMC) method based on the time delay integration (TDI) mode was analyzed using the optical injection formula of charge coupled devices (CCDs). The result shows that the non-synchronous effect of charge packet transfer caused by line-by-line transfer during exposure makes the compensated image dissatisfying. Then an improved electronic IMC method based on the CCD multiphase structure was proposed. In this method, a series of proper driving clocks were applied to drive the charge packet to move electrode-by-electrode during the exposure time, which results in a minimum non-synchronous effect of charge packet transfer. The mismatch of velocity between charge packet transfer and image motion was decreased. The performance of the improved electronic IMC method was also analyzed using the optical injection formula. The modulation degrees of the two methods were compared. The average value of the modulation degree of the improved electronic IMC method was 47/96, greater than the conventional electronic IMC method, which was 1/3. To achieve the improved electronic IMC, the driver timing diagram of the improved electronic IMC method was proposed. This paper presented an improved hardware implementation method for the improved electronic IMC method. Based on the basic FTF4052M drive circuit system, an IMC pulse pattern generator that worked together with the main pulse pattern generator (SAA8103) was added to achieve the improved electronic IMC. Then, the internal structure of the IMC pulse pattern generator was given. A dual pulse pattern generator drive circuit system was proposed. After computer simulation and indoor real shot verification, the compensation effect of the improved electronic IMC method was better than the compensation effect of the conventional electronic IMC method.