Terrestrial Transmission of Digital Television Signals (DVB-T) - Digital Video and Audio Broadcasting Technology - page 347

The DVB-T signal bandwidths are obtained from the subcarrier spacing
∆f of the respective channel (8, 7, 6 MHz) and the number of carriers actu-
ally used in 2K and 8K mode (1705 and 6817).

f signal DVB-T = N used_carriers • ∆f;

Table20.7. Signal Bandwidths in DVB-T

Channel
bandwidth

f signal DVB-T
of 2K mode

f signal DVB-T
of 8K mode

8 MHz 7.612 MHz 7.608 MHz

7 MHz 6.661 MHz 6.657 MHz

6 MHz 5.709 MHz 5.706 MHz

IFFT
bandwidth

Channel
bandwidth
8/7/6 MHz

IFFT bandwidth
9.1429 MHz (64/7) @ 8 MHz
8.0000 MHz @ 7 MHz
6.8571 MHz (48/7) @ 6 MHz

Central carrier
3408 [852]

Signal bandwidth
7.61 MHz @ 8 MHz
6.66 MHz @ 7 MHz
5.71 MHz @ 6 MHz

Signal
bandwidth

Subcarrier spacing
1.11 [4.46] kHz @ 8 MHz
0.98 [3.91] kHz @ 7 MHz
0.84 [3.35] kHz @ 6 MHz

Carrier # 0

Carrier # 6816
[1704]

Fig. 20.9. Spectrum of a DVB-T signal in 8K and [2K] mode for the 8/7/6 MHz
channel

In principle, there are two ways of counting the COFDM subcarriers of
the DVB-T channel. The carriers can either be counted through from 0 to
2047 or from 0 to 8192 in accordance with the number of IFFT carriers or
counting can begin with carrier number zero at the first carrier actually
used in the respective mode. The latter counting method is the more usual
one, counting from 0 to 1704 in 2K mode and from 0 to 6816 in 8K mode.
In Fig. 20.9. then the position of the spectrum of the DVB-T channel is