LSLIDAR C32 - Accurate Time Calculation of Channel Data; End Time of Data Point

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to obtain the 6-byte UTC time (more than 1 second) and 4-byte nanosecond
timestamp from the data packet. The addition of the two will be the exact time
when the data packet ends.
8.2 Accurate Time Calculation of Channel Data
To obtain the accurate time of the end of the data packet, knowing that each of
the 12 data blocks contains 32-channel light-emitting moments and the light-
emitting time interval of each channel, the accurate measurement time of each
channel data can be calculated.
8.3 End Time of Data Point
Each data block of the C32 lidar contains 32-channel measurement data.
Therefore, the end time interval of each data block (single echo mode) or each
parity block pair (dual echo mode) is 50,000 ns. Assuming that the absolute time
of the end of the data packet is T
Packet_end
, the steps for calculating the end time
of the data block T
Block_end
(N) are as follows:
Single Echo Mode
Each packet contains 384 data. The end time interval of each packet is the time
of the last point. Assume that the absolute time of the end of the packet is
T
Packet_end
and the end time of the previous packet is T
Packet_end_last
.
The end time interval of each packet is:
(T
interval
= T
Packet_end
- T
Packet_end_last
) / 384
Each packet contains 384 data points, the end time of each data point is:
T
Point_end
(N) = (T
Packet_end
- T
interval
*(384-N)), (N = 1,2,...,384)
Dual Echo Mode
Each packet contains 6 group of odd and even data blocks. As the timestamp of
the odd block is the same as the timestamp of the even block, each packet has
a total of 384 / 2 = 192 groups of odd and even data. As the time interval
between the end of each packet is the time of the last point, assuming that the
absolute time of the end of the packet is T
Packet_end
, the end time of the previous
packet is T
Packet_end_last
.
The end time interval of each packet is:
(T
interval
= T
Packet_end
- T
Packet_end_last
) / 192
Each packet contains 192 data points, the end time of each data point is:
T
Point_end
(N) = (T
Packet_end
- T
interval
*(192-N)), (N = 1,2,...,192)