Piletic, dipl. ing -Technical Assistant Director

Piletic, dipl. ing -Technical Assistant Director

Public company for broadcasting and transmission
“Broadcast Center”
MONTENEGRO
DVB-T
pilot project
Miloš Piletić, dipl. ing
Technical Assistant Director
What is
DVB?
► Digital Video Broadcasting
►
►
>270 companies, producers, operators, regulators, etc.
Standards (ETSI):
DVB-S (Satellite) od 1994
► DVB-C (Cable)
► DVB-T (Terrestrial) od 1998
► DVB-H (Handheld)
► DVB-DSNG
► DVB-MC
► ......
►
Goals:
►
►
►
►
►
►
►
How:
►
►
►
►
Open system for al data (HDTV, MPEG 2,IP,...)
Existing service zone broadening
Several programs in the same frequency channel
High received signal quality (video=DVD, sound~
sound~MP3)
No LOS reception
interactivity (MHP+Java)
SFN (SingleFrquencyNetwork
(SingleFrquencyNetwork))
Usage of OFDM (OrthogonalFrequencyMux) in the 8 MHz (UHF band) channel
● 2k FFT: 1705 carriers, f distance 4464 kHz
● 8k FFT: 6817 carriers, f distance 1116 kHz
Usage of QAM modulacije (QPSK, 16QAM, 64QAM)
● capacity 5-31 Mb/s depending of modulation
FEC tehchniques (Reed-Solomon, interleaving)
MPEG-2 stream broadcast, with video and audio content
● 4:2:0 profiled (distribution), 4:2:2 profile (contribution)
● bitrate: live video ≥4Mb/s, audio ≥128kb/s
PAL
DVB
PAL
DVB
DVB-T network planning:
►
SFN and/or MFN
ƒ SFN (SingleFrequencyNet) one channel for all net,
network gain, synchronization...
ƒ MFN (MultiFrequencyNet) lot of channels, poor
spectral efficiency, large capacity, different
coverage...
►
Gap filler DVB-T device
ƒ filling “gaps” from the main Tx
ƒ mini SFN
►
High capacity back-bone transmission
system, remote control of MPEG processing
equipment
ƒ STM-1, 155Mb/s and more...
ƒ Remote ctrl of the processing equipment
ITU situation:
RRC 2006, preparations, plans, ...
RTV Dom
Sjenica
200W, ch 67 (ch 35
SFN)
1kW, ch 35
Code rate 2/3, guard interval
1/8
Code rate 2/3
Guard interval 1/8
22,9Mb/s br
Rx equipment home:
HUMAX STB (F3 fox, DTT 4000)
Coverage: ch 67
RTV Dom
no LOS has no
effect inside
buildings in the
urban areas
Legend:
75 <= E < 120dBuV/m
65 <= E < 75dBuV/m
55 <= E < 65dBuV/m
45 <= E < 55dBuV/m
35 <= E < 45dBuV/m
25 <= E < 35dBuV/m
Coverage ch 35
Sjenica
Ongoing:
C/I measurements with
Albanian DTV
Propagation over water
Legend:
75 <= E < 120dBuV/m
65 <= E < 75dBuV/m
55 <= E < 65dBuV/m
45 <= E < 55dBuV/m
35 <= E < 45dBuV/m
25 <= E < 35dBuV/m
Conclusion:
-Service area dimension:
-Urban (high penetration, reflection, guard interval increasing)
-Suburban (poor reflection, no significant improvement)
-Mobile reception <40km/h
-Special measuremnts, 16QAM, C/I, co-channel, etc.
-Comparison with PAL (LOS areas, Rx similar)
-SFN
( 64 QAM, Code Rate 2/3, Guard Interval 1/8 )
Analogna
Sjenica (500 W)
RTV Dom (220 W)
CH 23
CH 29
CH 33
CH 35 ( 586 MHz )
CH 67 ( 842 MHz )
1023 W
810 W
486 W
R.B
R.
Lokacija
Nivo [dBμV]
CSI
[%]
BER
W
P
Nivo [dBμV]
CSI [%]
BER
W
P
Nivo [dBμV]
Nivo [dBμV]
Nivo
[dBμV]
1
Vas Impeks
54,6
28
1.0 E7
⁄
⁄
⁄
⁄
⁄
55,3
51,0
50
2
Smokovac most
57,8
27
1.2 E6
⁄
⁄
⁄
⁄
⁄
61
59,3
58
3
Stadion Koma
73,3
24
1.0 E7
⁄
32
⁄
⁄
⁄
80,6
79,4
74,5
4
Semafori pumpa
70,3
24
1.0 E7
⁄
23
⁄
⁄
⁄
71,6
73,4
73,3
5
Autootpad Ivanović
66,5
24
1.0 E7
⁄
35
⁄
⁄
⁄
74,3
72,5
69,2
6
Semafori Bocola
56
25
1.0 E7
⁄
30
⁄
⁄
⁄
60,8
58,5
54
7
Strelište
62,5
25
1.0 E7
⁄
41
44
2.1 E3
⁄
59
55,4
53,4
8
Pumpa
"Dekar"
76,2
25
1.0 E7
⁄
43,7
48
2.3 E3
⁄
70,9
68,4
69
1 0 E-
Neighbours:
►
Croatia:large P for big areas, small P for Zagreb and vicinity
►
Albania: four DTV networks (unknown mode)
►
Serbia: testing in Belgrade and vicinity
►
Macedonia: testing in Skoplje
►
Slovenia: MFN
Thank You for
Your attention!