An infant seat includes a shell having sidewalls and a handle having arms attached to the sidewalls. The structural reinforcement includes an upper portion which defines a rear-window opening and a lower portion which extends the upper portion toward the bottom of the trunk lid. The bit error rate and accuracy of the recovery are optimized without centering of oversampling. The carrier may be detachably mounted on a cover ring, on the shield, or on the interior of the chamber sidewall.