Bug 1073 - Matlab lidar reader not properly computing signal
Summary: Matlab lidar reader not properly computing signal
Status: RESOLVED FIXED
Alias: None
Product: DIRSIG4
Classification: Unclassified
Component: LIDAR (show other bugs)
Version: 4.5.2-release
Hardware: Other Other
: P5 normal
Assignee: Scott D. Brown
URL:
Depends on:
Blocks:
 
Reported: 2013-11-18 01:28 EST by Paul Romanczyk
Modified: 2014-01-02 08:11 EST (History)
1 user (show)

See Also:


Attachments

Note You need to log in before you can comment on or make changes to this bug.
Description Paul Romanczyk 2013-11-18 01:28:10 EST
The MATLAB readProtoLidar function improperly combines the active and passive parts of the signal. The active part of the signal has units of photons and the passive term has units of photons/sec. 

Line 39 of extra/matlab-lidar/readProtoLidar.m should read:
realReturn = pulseData(2:end,detIdx) + pulseData(1,detIdx) * timeBinWidth;

where timeBinWidth should be previously defined as:
if pulseHeader.timeGateBinCount == 1
   % avoid those pesky divide by zeros (although we should rarely have a single bin lidar system).
   timeBinWidth = ( pulseHeader.timeGateStop - pulseHeader.timeGateStart );
else
   timeBinWidth = ( pulseHeader.timeGateStop - pulseHeader.timeGateStart ) / double( pulseHeader.timeGateBinCount - 1 );
end
Comment 1 Scott D. Brown 2013-11-18 09:11:27 EST
I will make sure we check that in.
Comment 2 Scott D. Brown 2014-01-02 08:11:04 EST
We checked in a set of updates that Paul submitted for the main read routine, which will be in the 4.5.3 release.