DVB-T2

DVB-T2 offers four different modulation schemes: QPSK, 16-QAM, 64‑QAM, and 256-QAM.

Lower order modulation formats like QPSK do not transmit data as fast as the higher modulation formats such as 64‑QAM, but they can be received when signal strengths are lower.

Note that as the QAM order increases, there is a higher possibility of introducing data errors since these schemes are less resilient to noise and interference.

Match the code rate to the requirements of the broadcast network. The higher the level of error correction that is applied, the greater the level of supporting error correction data that needs to be transmitted, which reduces the data rate of the transmission.

For example, if you select 2/3, for every 2 bits of data, you are sending out 3 bits, one of which is for error correction.

Choose the appropriate guard interval so that distinct transmissions do not interfere with each other.

In DVB-T2, five guard intervals are available: 1/128 provides the lowest protection and the highest data rate, 1/4 results in the best protection but the lowest data rate.

Pilots are needed to adapt transmissions to current channel conditions. DVB-T2 has eight different patterns. Choose the appropriate pattern depending on network type and reception conditions or select ‘Auto’.

If you choose a specific pattern, you can also set the frame duration and forward error correction (FEC) block size.

This is a trade-off parameter, with shorter FEC blocks giving finer control over achievable bit rate but requiring more overhead and thus not as efficient as long frames.

Choose between short FEC frame (16,200 bits) and long FEC frame (64,800 bits).