
The packet data structure for Single Return Mode is shown in
. The packet data structure for Dual Return
.
There are several key differences between the packet structures.
First, in Dual Return Mode the sensor sends a pair of data blocks for each azimuth angle firing. The odd numbered blocks
(1, 3, ..., 9, 11) contain either the strongest or second-strongest return and the even numbered blocks (0, 2, ..., 8, 10) con-
tain the last return.
If the strongest return is also the last return, then the second-strongest return is provided. If only one return was detected,
the data will be identical in the even|odd block pairs (0|1, 2|3, 4|5, 6|7, 8|9, 10|11).
Figure 9-2 VLP-16 Single Return Mode Data Structure
Chapter 9 • Sensor Data
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