We propose a framework for Google Map aided
UAV navigation in GPS-denied environment. Geo-referenced
navigation provides drift-free localization and does not require
loop closures. The UAV position is initialized via correlation,
which is simple and efficient. We then use optical flow to
predict its position in subsequent frames. During pose tracking,
we obtain inter-frame translation either by motion field or
homography decomposition, and we use HOG features for
registration on Google Map. We employ particle filter to
conduct a coarse to fine search to localize the UAV. Offline
test using aerial images collected by our quadrotor platform
shows promising results as our approach eliminates the drift in
dead-reckoning, and the small localization error indicates the
superiority of our approach as a supplement to GPS.