Ingenieurbüro Mulka
The world of bit streams is our business.
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– Ingenieurbüro Mulka
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Accompanying tests in tuner development
Tests regarding the tuner hardware and firmware components like the Viterbi decoder of your
receiver will be possible with the PRBS-Analyser. For these tests, your receiver under test
must have an RDI output. Moreover, a DAB-XPlorer or alternatively, a test signal generator
that can replay ETI files will be required.
Use the RDI-ETI-Converter to replace the sub-channels of a recorded ETI / EDI file with
pseudo-random binary sequences. Feed the resulting ETI / EDI file into a test transmitter
DABRF-TX. Use the DAB-XPlorer with the PRBS-Analyser to do a true bit error analysis at
the RDI output of your receiver.
5.3.6 Test of transmitter components
Setup
•
DABXP-HWU
•
DABXP-BASIC
•
DABXP-OCO
•
DABRF-HWU or DABRF-RM
•
DABRF-RX
•
DABRF-PC
•
DABXP-OPR
•
optional DABXP-OTR
Uses
With the above setup, we first use the DABRF with the Recorder application to catch a DAB
multiplex from an on-air signal. Afterwards, use the RDI-ETI-Converter to convert the
recorded EDI file into an ETI (NI or NA) file. Use the DAB-XPlorer to replay the so prepared
ETI file into the input of your transmitter under test.
(1) Replace the sub-channel content by pseudo-random binary sequences. Together
with the PRBS-Analyser, you can use the so prepared ETI files to assess the coding
quality of your transmitter. The PRBS-Analyser measures not only the bit error rate
but shows as well error positions within the frame and over the time thus allowing you
to locate bugs in, for instance, the modulator firmware.
(2) Use the post-processing functions of the RDI-ETI-Converter software to insert a FIC
marker and replace the TIST. Together with a sampling oscilloscope, this will allow
you measuring the operational delay of the COFDM modulator.
(3) Again, use the post-processing functions to insert random bit, frame or CRC errors
into your ETI stream. Put the DABRF on the transmitter output, and check the
behaviour of your transmitter with the corrupted ETI input.
(4) Use the Triggered Recorder to catch real world scenarios of corrupted ETI input.
