Standardized DVB-T2 RF specifications - DigitalEurope

10- 2- MFN multipath performance
10- 2- 1- Performance with short echoes
The receiver should provide PFP1 for the C/N values shown in Table 14 when the channel
profile in Table 13 is applied. All paths have zero phase at the channel centre. The DVB-T2
signal should be set to -50 dBm at the tuner input.
Note that due to the short echo delays in Table 13, some test equipment does not report
back the correct C/N.
Table 13 – Short echo test profile
Tap Delay (µs) Relative Attenuation (dB)
1 0 2,8
2 0,05 0
3 0,4 3,8
4 1,45 0,1
5 2,3 2,6
6 2,8 1,3
Table 14 – C/N Requirements for Short Echo Profile (PFP1)
Mode C/N dB
5 – 32KN 256Q 3/5 1/32 PP4 8MHz 21.5
6 – 32KN 256Q 3/5 1/8 PP2 7MHz 22.0
7 – 32KE 256Q 2/3 1/128 PP7 8MHz 22.7
8 – 32KE 256Q 2/3 1/16 PP4 8MHz 23.4
9 – 32KE 256Q 3/4 1/32 PP6 8MHz 25.7
11- PERFORMANCE IN TIME VARYING CHANNELS
Receivers should handle expected time variations of paths to fixed roof-top reception. Such
variation is caused by the swaying of masts, antennas and branches of trees etc. Normally
the required C/N increases with frequency separation as shown in Figure 2.
The increase in required C/N for PFP1 reception should be less than or equal to the Δvalue
shown in Table 15 for a 20μs 0dB echo with 0º phase at the channel centre using the
frequency separation shown, when compared to a 20μs 0dB echo with frequency separation
equal to 1 Hz (Doppler shift of +/- 0.5Hz after AFC). The DVB-T2 signal should be set to -50
dBm at the tuner input.
Note: On a typical channel simulator, a frequency separation of 10Hz corresponds to a “Pure
Doppler” setting of 10Hz (+/-5Hz after receiver AFC), which at 666MHz with a frequency ratio
of 1.0, corresponds to a speed of 4.5m/sec or 16.2km/hr.
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