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SMATV systémy

Terra multiswitch system - from design to implementation
Shared antenna systems (usually called SMATV systems - Satellite Master Antenna TV) are typically mounted in apartment buildings (condominiums), usually managed by housing cooperatives or property management companies. In each case the owner or manager of the facility should ensure trouble-free operation of the antenna system providing access to terrestrial (DVB-T, FM/DAB) and satellite (DVB-S/S2) broadcasts.
This article concisely presents the process of designing and implementing a multiswitch system in one of multifamily buildings in Krakow - from specification of requirements for the project to the completion and operation of the system.
1. System requirements
The lack of the list of requirements that should be known before any investment is often the source of many problems in the next stages of the implementation. Sometimes it is caused by a lack of the basic knowledge of antenna systems among developers, which is the reason that the final shape of the installation in multi-family buildings, and even entire housing developments must be decided by the installation company.
In many countries the minimum requirements are defined by local law. In Europe, the residents should usually have access to digital terrestrial TV (DVB-T), analog FM radio, DAB radio, cable TV services, and often to satellite broadcasts from one or two satellite positions (Hotbird and Astra).
In the case of the described system, there were the following assumptions and requirements:
  • distribution of DVB-T, FM, DAB, SAT (Hotbird 13.0E) signals
  • building with 5 floors and 5 staicases
  • 24 outlets in apartments located in each staircase
  • vertical cable duct in each of the staicases
  • possibility of installation of horizontal cabling below the ground level (in basement/garage)
2. Selection of the multiswitch system
The market offers many types of multiswitches. When choosing the suitable equipment, the investor and installer should pay attention to its technical parameters and completeness. The completeness means both a variety of versions for different applications, a wide range of accessories, as well as technical support. Other significant factors are the experience and reputation of the manufacturer, guarantying high reliability backed by an extended warranty.
Terra equipment for multiswitch systems ensures:
  • highest technical parameters and 4-year manufacturer warranty
  • full range of devices and accessories: line amplifiers, TV and FM/DAB amplifiers, multiswitches, passive components
  • free software for designing complex systems - more
  • library of CAD files additionally helping designers in developing specific projects and in preparing construction documentation
3 . Design of the system
Implementation of SMATV system in a multifamily building should be guided by the design taking into account information such as the number and layout of the outlets, which usually determines the topology of the system and selection of multiswitches, splitters and taps, and the parameters of the distribution network: levels of input signals, gain of amplifiers, attenuation of cables and passive components of the system. The designing process consists in selecting the elements of the system and adjusting their parameters so that the output signals are compliant with current standards and recommendations.
Below we present the design of the system for the building (see the assumptions and requirements above), created with the use of SatNet software. The system in the residential building in Krakow has been based on TERRA multiswitches of MV-5XX series. The signal lines are split for the subnetwork in each staircase with the use of 5-path SAT/TV splitters and SAT/TV taps with appropriate attenuation levels.
Download the design (*.STN).
The layout of the system: 5-cable bus runs from the master antenna on the roof of the building to the amplifiers located in the upper part of the middle staircase, then is led downwards in the vertical cable duct to the basement level, split and led horizontally to other staircases. Each staircase is equipped with installation box with multiswitch for distribution of the signals to outlets in apartments in the staircase.
4. Implementation
The master antenna consists of directional UHF antenna Dipol 44/21-69 Tri Digit A2670 with gain of 16.8 dBi, FM antenna Dipol 1RUZ B A0210, DAB antenna (BIII) A0140, 100 cm satellite dish TRIAX 100 TD A9645 with QUATRO LNB Inverto BLACK Ultra A98266. All the components are mounted on 3-meter steel mast E903830, which has been attached to the wall of an exhaust stack with the use of wall bracket OMP-50L40 E8552.
View of the components in the installation box located in the upper part of the middle staircase
The signals from the master antenna are run via five Triset-113 PE E1017_100 cables to the set of amplifiers placed in metal box TPR-7 R90561 (500x500x200 mm) mounted in the upper part of the middle staircase. SA-51 TERRA R70501 amplifier for 5-input multiswitches equalizes SAT IF signals (four polarization-band pairs) and provides power to active components of the system (LNB, multiswitches). DVB-T signals are processed by four-channel TV amplifier Terra at440 R82511, a highly selective tunable RF amplifier capable of filtering, amplifying and equalizing four digital multiplexes broadcast in the UHF band. The paths are equipped with automatic gain control (AGC) ensuring high and stable output levels of the DVB-T signals. FM/DAB signals are amplified by FM/VHF/UHF amplifier ma400 R82520. The both amplifiers of the terrestrial signals are powered from the DR-60-12 R82532 power supply and placed on DIN rail. All the active devices at the input of the system are grounded and protected against overvoltages by TV-Sat surge protectors Signal R48602.
All the terrestrial signals enter the Terr. TV input of the SA-51 amplifier. The output terrestrial and satellite signals from the amplifier are led through five coaxial lines to another TPR-7 R90561 box located in the basement of the building. The ends of the lines are marked with colors compliant with appropriate markings on the inputs of splitters, taps and the MV-524 R70724 multiswitches. The die-cast metal housings of the devices ensure high screening efficiency and great resistance to RFI. The 5-cable bus is extended to the rest of the staircases by 5XX taps with suitable attenuation levels and enters the inputs of the MV-524 R70724 multiswitches.
View of the equipment extending the 5-cable bus to other staircases.
The devices are located in the basement in the middle staircase,
with the multiswitch distributing signals to apartments located in this staircase.
The picture above shows the SD-520 R70518 tap extending the 5-cable bus, MV-524 R70724 multiswitch distributing signals to 24 outlets located within the middle staircase, and SD-504 R70517 splitter for extending the bus in both directions, to the rest of the staicases. All the components are placed in another TPR-7 R90561 box.
The inside of the installation box located in the second staircase
The bus is extended in the second and fourth staircases with the use of SD-515 R70517 taps. The MV-524 R70724 multiswitch located together with the tap in each of the staicases provides signals to outlets located there. The components in these staicases are also mounted in placed in TPR-7 R90561 boxes.
The signals from the antenna sets are carried to the system components located in the building by Triset-113 PE E1017_100 cables, with PE jacket resistant to UV radiation. In order to ensure comprehensive protection of the SMATV system against lightning surges, the lines from antennas are connected via TV-Sat surge protectors SIGNAL R48602. The indoor distribution system uses Triset-113 E1015_500 cable, with white PVC sheath. There have been also used "Self-install" compression F-connectors Cabelcon E80410.
The actual signal quality and levels were measured with Digiair PRO R10510 (DVB-T meter) and Satlook Micro HD R10740 (DVB-S/S2 meter).
The list of the equipment and cables used in the system:
Steel Satellite Dish TRIAX 100 TD (100 cm)A96451
UHF TV Antenna DIPOL 44/21-69 Tri DigitA26701
FM Antenna Dipol 1RUZ PM BA02211
DAB / Band III Antenna DIPOL-4/DABA01401
QUATRO LNB Inverto BLACK Ultra 0.2dBA982661
TV-Sat Surge Protector SIGNALR486026
Four-channel Amplifier Terra at440R825111
Multiband Amplifier Terra ma400 (FM/VHF/UHF)R825201
DC Distribution Cable 780.20R825371
DIN Rail Power Supply DR-60-12R825321
DIN Rail Rack Mounting BracketR825381
Amplifier for 5-input multiswitches Terra SA 51R705011
SAT/TV Splitter Terra SD-504R705151
SAT/TV TAP: Terra SD-520R705181
SAT/TV TAP: Terra SD-515R705172
Multiswitch Terra MV-524 (5-in, 24-out)R707245
Subscriber Terminal Outlet Signal R-TV-SATR694100120
F-plug Cabelcon (for RG-6/Triset-113, "Self-Install")E80410130
Metal Housing/Box: TPR-7 (500x500x200mm)R905616
Coaxial Cable 75 ohm TRISET-113 PE (gel-filled)E1017_125 m
Coaxial Cable (75 ohm) TRISET-113E1015_5001920 m
Examples of other SMATV systems based on TERRA equipment
Multiswitch system with 180 outlets in two buildings
SMATV multiswitch system for 198 subscribers
Large SMATV multiswitch system for a housing development (1215 outlets)
Multiswitch system in a high-raiser
Multiswitch system with 189 outlets