A method for identifying potential targets as far away as possible is
disclosed. In a simple background scene such as a blue sky, a target may
be recognized from a relatively long distance, but for some high clutter
situations such as mountains and cities, the detection range is severely
reduced. The background clutter may also be non-stationary further
complicating the detection of a target. To solve these problems, target
detection (recognition) of the present invention is based upon temporal
fusion (integration) of sensor data using pre-detection or post-detection
integration techniques, instead of using the prior art technique of
fusing data from only a single time frame. Also disclosed are
double-thresholding and reversed-thresholding techniques which further
enhance target detection and avoid the shortcomings of the traditional
constant false alarm rate (CFAR) thresholding technique. The present
invention further discloses improved spatial fusion techniques for target
detection (recognition) employing multiple sensors instead of employing
the more conventional single sensor techniques. If spatial fusion is
implemented with more than three sensors, then target detection can be
enhanced by also using post-detection techniques. Moreover, since the
pre-detection and the post-detection technique are complementary to each
other, a combination of these two integration techniques will further
improve target detection (recognition) performance.