User's Manual Part 1

CL1TC-4 400W DVB-H Transmitter WEB Interface
Product Manual, Rev. 1 59
6.4.1 Modulator Mode
T
his page allows the users to select the Modulator Mode and the Test Mode.
Figure 6-10 Modulator Mode Configuration
The available parameters are:
Item Option
Modulator Mode Normal, CW, Test1 (Carriers Removal), Record , Playback
Table 6-2 Modulator Mode Parameters
CW and Test 1 are special test modes not used in regular operation. The CW mode
generates a narrow-band frequency tone. This is useful for phase noise measurements or
to view background noise. The Test 1 mode suppresses a subset of the carriers from the
center of the DVB-H signal. This is useful for simulating a notch fading event or to view the
background noise present in the band. In the “Test 1” mode, usually 500 carriers are
removed. The number of removed carriers can be factory configured from between 100 to
800 via the advanced access interface.
The Record mode allows the user to record a input data stream (limit of 16 megabytes) for
later playback. The modulator must first be set to SFN mode, a valid SFN input stream
must be present and no input stream alarms can be reported.
After recording, the modulator will automatically switch back to Normal mode. The user can
check the Global Status page to see that the modulator is back in Normal mode and that the
stream has been recorded. The user can check also the “List Uploaded Files” screen under
“System Parameters” to see the file name displayed.
In the Playback mode the recorded input stream is used to generate a modulator output.
This is useful for detailed system testing especially when an input signal is not available or
for benchmark testing using a known test signal.