Electronic And Postal Communications (Digital and other Broadcasting
Networks)
G.N. No. 418 (contd)
In this network the inter-transmitter distance is 25 km in the case of portable and mobile receptions.
It is therefore possible to use a value of 1/8 Tu (8k FFT) for the guard interval
The same guard interval value might also be feasible for fixed reception, with its greater distance between
transmitters of 40 km, since fixed roof-level reception is less sensitive to self-interference because of the
directional properties of the receiving antenna.
The parameters and the power budgets of this network given in Table 3 shall be used.
III: Small service area SFN for urban environment (Table 4)
(a) The geometry of the transmitter lattice of this network and the service area are identical
to those of Small Service Area SFN, dense
(b) This network applies to: fixed, outdoor/mobile and indoor reception, for both Band III
and Bands IV/V.
(c) This Network is intended for small service area SFN coverage in an urban environment.
TABLE 4: PARAMETERS OF SMALL SERVICE AREA SFN FOR URBAN ENVIRONMENT
RPC and
RPC 1
RPC 2
RPC 3
reception type
Fixed antenna
Portable outdoor
Portable indoor
and mobile
Type of network
Open
Open
Open
Hexagon
Hexagon
hexagon
Number of transmitters
3
3
3
Geometry of transmitter
lattice
Triangle
Triangle
Triangle
Distance d (km)
40
25
25
Service area diameter D (km)
53
33
33
Tx effective antenna height
(m)
150
150
150
Non-directional
Non-directional
Non-directional
Band III
24.1
32.5
40.1
Bands IV/V
31.8
44.9
52.2
Geometry of service area
Tx antenna pattern
e.r.p.*
(dBW)
The e.r.p. is given for 200 MHz in Band III and 650 MHz in Bands IV/V; for other frequencies (f
in MHz) the frequency correction factor to be added is: 20 log10 (f/200 or f/650) for RPC 1 and 30
log10 (f/200 or f/650) for RPC 2 and RPC 3.
* The e.r.p. values indicated in this table incorporate an additional power margin of 3 dB.
IV: Semi-closed small service area SFN (Table 5)
(a) This network is intended for cases in which increased implementation efforts regarding
transmitter locations and antenna patterns are undertaken in order to reduce the outgoing
interference of the network.
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