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DVB-T and DVB-T2 Transmitter
Test Challenges
Application Note
Introduction
Over the past 10 years, DVB-T has become the most widely adopted and
deployed terrestrial digital video standard. It is now well established and the
prices of DVB receivers have dropped over time as the technology has matured.
Due to its successful development and deployment, DVB-T has come to serve
as a sort of benchmark for the development of other terrestrial digital video
standards.
Due to increasing scarcity of spectrum and requirements for high transmission
capacity in recent years, an updated standard with more spectral efficiency
is required to replace DVB-T. The DVB-T2 system is capable of meeting these
requirements, due to its increased capacity, robustness, and the ability to reuse
existing reception antennas. The regions which previously adopted DVB-T sys-
tems, primarily countries in Europe and Asia, will be migrating to DVB-T2, while
many new countries and regions began the process of adopting DVB-T2 directly
since the first version of the standard was published in 2009.
With the advanced technologies used in DVB-T2 to achieve high performance
levels, measurement challenges face both transmitter and receiver developers.
In this application note, we will focus on the transmitter test measurement
challenges.
Overview of the DVB-T and DVB-T2 Standards and Transmitter Structures
DVB-T and DVB-T2 standards overview
Both DVB-T and DVB-T2 use the OFDM modulation The combination of the parameters in Table 1 can result
scheme, which provides various options for bandwidth, in numerous test cases. DVB-T2 provides more options
modulation, FEC (forward error correction) rates, number of than DVB-T, enabling higher efficiency and flexibility, and
carriers, and guard intervals, making it flexible enough to supports more advanced technologies, such as multiple
meet the needs of different transmission environments and PLPs, LDPC coding, and MISO, resulting in increased signal
operators. and test complexity, especially for a MISO configuration.
Overall, while there are similarities between the two
The key features of the DVB-T and DVB-T2 technologies systems, the broader set of features in the DVB-T2 system
are listed side by side in Table 1. allows it to offer both a much higher data rate than DVB-T
and a much more robust signal.
Table 1. Comparison of the key features of the DVB-T and DVB-T2 systems
Features DVB-T DVB-T2
FEC Convolutional coding + RS:1/2, 2/3, 3/4, 5/6, 7/8 LDPC + BCH: 1/2, 3/5, 2/3, 3/4, 4/5, 5/6
Modulation QPSK, 16QAM, 64QAM QPSK, 16QAM, 64QAM, 256QAM with constellation
rotation
Guard interval 1/4, 1/8, 1/16, 1/32 1/4, 19/128, 1/8, 19/256, 1/16, 1/32, 1/128
FFT size 2 k, 4 k, 8 k 1 k, 2 k, 4 k, 8 k, 16 k, 32 k
Scattered pilots 8% of total 1%, 2%, 4%, 8% of total
Continual pilots 2.0% of total 0.4% - 2.4%
Bandwidth 5, 6, 7, 8 MHz 1.7, 5, 6, 7, 8, 10 MHz
Typical data rate 24 Mbit/s 40 Mbit/s
Max. data rate (@ 20 dB C/N) 31.7 Mbit/s 45.5 Mbit/s
2
Transmitter structure overview