| 摘要 |
<p>A method (100) of projecting into space, from a first object, a plurality of modulated lines to form a grid defining a first relative reference frame, the method (100) includes simultaneously projecting into space from the first object a horizontal grid line and a vertical grid line to form a set of grid lines (102), modulating the horizontal grid line and the vertical grid line to carry first and second grid words, respectively (104 and 106).</p> |
