Technical data

DOC-01-TELAS-CRG-4 ASTi ACE Studio Components Reference Guide Rev.M
28 Copyright © 2014 Advanced Simulation Technology inc.
2.11. Level D Capture
Summary: The Level D Capture component is used to record audio for Level D
compliance testing. The audio recorded by this component can be compared
spectrally to the reference audio, in real time with the scope or offline with the
spectral analysis capability accessible through RMS.
Description: To record audio using the Level D Capture component, link the
record audio coming in through the ACU to the Level D Capture component. In the
sound library add the aircraft reference recordings, set the path value and index
number. In the Level D Capture component set the test number to match the file’s
index number, this selects the reference file to run with the test recordings. Record
the audio. The recording then goes to a file on the Target. The file number will look
something like this:
library000_group65535_index00 “x”
The ‘65535’ signifies the Level D recording file. The ‘X’ is the test number.
Host control can direct the test number and the start variable.
In the Level D Capture component:
1. Select the library and group object (these are set in the Sound Library)
2. Set the ACU gain level to match the level of the reference recording.
3. Add the table function to calculate the gain level with the calibration number.
(This is the number calculated during calibration of the ACU with the micro-
phone.)
4. Set the ‘x’ to the test case number and the ‘f(x)’ to the calibration number.
This value is sent to the ACU.
5. Set the ‘Record Length’ function for each test case to match the amount of
time the file was recorded.
6. Set the maximum record time.
After recording the audio, open RMS and navigate to the Audio > Spectral Analysis
page. Select the waveset that contains the reference files and RMS will
automatically link up the reference file to the recorded file. Check the box to
compare the files and/or create a difference plot to show the margin of the
difference. Click the ‘Start Spectral Analysis’ button and RMS generates a .pdf file
of the results.
Audio Inputs
RecAudio
Type Default Value
boolean False
audio n/a
Description: The input is the audio typically coming in from a
microphone linked to an ACU. The audio is recorded.
Note: Similar to the Record Replay component.
Control Inputs
ACUGain
Type Default Value
function n/a
float32 1.0
Description: Insert a table function containing the ACU gain corre-
sponding to the current test number.
RefAudio
Type Default Value
playsound_library 0
playsound_group 0
playsound_sound 1
Description: The reference audio for comparison.
Playsound_LibraryID: Selects the library from the soundlibrary
containing the reference audio file to be played.
Playsound_GroupID: Selects a group from the soundlibrary con-
taining the reference audio file to be played.
Playsound_SoundID: Selects a sound file from the soundlibrary.
Note: Similar to the Playsound component.