Unicable
Unicable is a method for distributing satellite television signals in a satellite system . Several receivers (currently with EN 50607 a maximum of 32) can be connected to just a single line, which is not possible with conventional satellite block distribution (star distribution in multi-switch operation). The antenna sockets can be divided as required, in series or in parallel with a distributor. It is important that so-called through sockets must be used when connecting in series. This makes Unicable technology particularly suitable for switching from cable television to satellite reception. In contrast to common single-cable systems with a limited selection of programs, Unicable provides the full program spectrum (regardless of whether it is SD, HDTV, 3D and / or UHD TV). A maximum of two satellites can be fed in this way via Unicable.
Unicable is a registered trademark of FTA Communications SARL (whose trademarks are, for example, "Inverto" and "Lemon"). In the German-speaking world, it is often equated with the European single-cable standard English satellite channel router ( SCR ) or English Channel Stacking System ( CSS ). However, Unicable is only an implementation of the trademark owner that is compatible with the SCR / CSS CENELEC EN 50494 standard .
function
The entire frequency band is not transmitted. Instead, each receiver has a specific frequency, the user band , or UB for short , in the satellite frequency range (950–2400 MHz). A receiver uses special DiSEqC signals to inform the distribution unit ( LNB or multi-switch ) of the level and transponder of the desired program. The transponder is then transferred to the user band of the receiver. To control a Unicable LNB, special DiSEqC switching signals are required, which is why only DVB-S receivers that support this standard will work in such a system. The basis for this technology is a European standard issued in 2004 (EN 50494). In principle, all receivers that meet this standard can be operated in a Unicable system. Conversely, these SCR receivers ( satellite channel routers ) or CSS receivers ( channel stacking system ) can be operated on all other satellite systems.
The SCR or CSS implementations of different manufacturers can differ in the number and distribution of the assigned frequency blocks (called "Unicable frequency"). These frequency blocks often have to be set manually when installing the receiver, but they can also be assigned automatically using an algorithm named in the standard. Each available Unicable frequency may only be assigned to one receiver, which means that the number of available Unicable frequencies also indicates the total number of receivers to be installed (Unicable LNBs = max. Four Unicable frequencies / Unicable multiswitches = max. Eight Unicable Frequencies). A twin receiver must be counted as two receivers because it has two integrated tuners / receivers. Each tuner / receiving part of the receiver must be assigned its own Unicable frequency in order to enable separate and error-free use.
There is a special switch-on command to identify the frequency blocks, in which all free frequency blocks are switched on with a continuous tone (beacon). Here the tuner or receiver must recognize the beacons by means of a blind scan. Since no return channel is provided for communication between the receiver and the multiswitch , the possibilities of the multiswitch must be queried explicitly. The multi-switch then "answers" by means of the beacon in the middle of the requested band (= yes, available, free) or with a frequency offset of 20 MHz (= no, not available, rejected), which in turn has to be evaluated by the receiver tuner. In this way, all parameters of the multiswitch can be queried one after the other.
In the case of an automated installation, the tuner may a. So ask for the allocation of a frequency block, the multiswitch then responds with the "yes" or frequency-shifted "no" tone. The requests are then modified, if necessary, until all the desired settings between the receiver and the multiswitch have been synchronized. The problem here is that other receiving devices that are in operation are disturbed during this installation.
The reliability of the sound beacon detection depends on the tuner / demodulator components used in the receiver and on the level ratios (especially the inclined position) at the connection point. For this reason, EN 50494 explicitly requires a manual input option for the user band ID and user band frequency in the receiving device.
In contrast to EN 50494, the successor standard JESS (EN 50607) supports bi-directional DiSEqC communication and thus enables the exact query of available, used and protected user bands and their frequencies. The installation of a receiving device can be considerably simplified with this aid. The implementation of bi-directionality in JESS distribution components is compulsory, in receiving devices it is optional, in order to make an upgrade of existing receiving devices possible via firmware update (every EN 50494-compliant receiving device can be made JESS-capable without hardware changes via firmware update).
The single-cable standard EN 50494 is clearly intended for applications within a residential unit ("single dwelling installations"). There are several approaches to using the system in multi-party house cabling. One approach is to provide each apartment with its own derivative. If this is not possible, there is an extension in EN 50494, whereby individual user bands can be protected against unauthorized access by a PIN code. The PIN code is optional and not supported by every receiver. If this protection is used, special antenna sockets should be used, e.g. B. the "ESU33" from Kathrein. This socket monitors the level of the remote supply voltage and starts a timer after a voltage jump from 14 to 18 V. If the voltage remains at 18 V for longer than 500 ms, the socket isolates the receiver from the distribution network with direct current. This 18 V (in normal reception mode, this stands for the horizontal switching voltage) is only required for the Unicable switching process for this short time and would paralyze the system if it was used for a longer period of time. The can function is patented for Kathrein. Another approach to the protective function is an antenna socket which monitors the control commands from the receivers and only allows the control commands permitted for the respective socket (= apartment) to pass (JULTEC JAP series). The system installer determines the authorization to which user tapes can be accessed from the respective antenna socket (with an antenna measuring device or operating software and USB dongle). This can function is patented for JULTEC. The sockets support both EN 50494 and JESS (EN 50607) and provide the receiving device via JESS with information about the user bands allowed on the socket.
compatibility
EN 50494 compatible end devices and LNB / multiswitches should be able to communicate with each other without any problems, provided that all settings on the receiver such as the UB frequencies or LNB oscillator frequency (universal or wide band) can also be set. Unicable compatible devices are at least suitable for Unicable LNBs / multiswitches, i. H. tested by the manufacturer. The necessary UB frequencies are then often already stored in the receiver software, but can now be set manually on almost all devices (EN 50494 requires a free input option). Unicable LNBs with a wide band oscillator (only the "Kathrein UAS481" with 10,200 MHz) are much more limited when it comes to end devices, since z. B. Sky receivers only provide universal oscillator frequencies (9750 and 10,600 MHz). However, the manufacturers / suppliers of LNBs have agreed not to introduce any new "broadband LNBs", but rather to equip any LNBs with "broadband hardware" with a universal LNB emulation mode via software adaptation. Universal LNB end devices from quality manufacturers (meanwhile also for DVB-S / S2-SAT receivers integrated in TVs) are actually all already prepared for Unicable / SCR, the standard (EN 50494) has largely established itself there too.
The VDR (" Video Disk Recorder ") program running under Linux is compatible with both EN 50494 ("SCR / Unicable") and EN 50607 ("SCR / JESS"). All satellite receivers with the Enigma2 operating system now also master the Unicable standard according to EN 50494 and EN 50607.
Unicable in LNBs
With this solution, the Unicable functionality is already housed in the LNB . Unicable-LNB standardized according to the EN 50494 protocol can be connected to a maximum of four receivers (tuners) directly via a cable to the LNB. Then only another conventional satellite distributor is required. Newer Unicable II LNBs standardized according to the EN 50494 / EN 50607 protocol can supply up to 32 receivers (tuners) directly via one cable. If more connections are required, a solution with (cascadable) Unicable multi-switches must be selected.
A Unicable LNB receives the satellite signals in the same way as a conventional LNB: The four different frequency bands, vertical / low band, horizontal / low band, vertical / high band and horizontal / high band are each amplified with low noise and integrated into the satellite IF -Band mixed down. You will encounter an integrated multi-switch that selects the desired reception level for each receiver. There is now a so-called SCR module for each connectable receiver. With an adjustable frequency generator ( VCO ), this mixes the transponder selected by the respective receiver down to its UserBand frequency. The signal is then filtered and fed into the coaxial cable with appropriate amplification . The whole process is controlled by a central microcontroller , which also decodes the DiSEqC commands from the receiver.
Common Unicable LNBs usually have two or even three outputs: A Unicable connection, to which up to four Unicable-compatible end devices can be connected, and one or two further so-called legacy connections, each of which has a conventional non-connection -Unicable-capable receiver can be connected.
Although the industry has agreed that all LNBs should behave like universal LNBs, there are also LNBs with unusual oscillator frequencies that require special receiver settings (see web links below, the setting of a receiver for "Unicable operation" is explained).
Unicable in multiswitches
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The Unicable functionality can also be integrated in multi-switches instead of in the LNB (with EN 50494, a maximum of eight receivers can be supplied via one cable). This enables a mixed network of cables (conventional distribution and unicable), which enables an extensive distribution network and is particularly suitable for bridging the last few meters of antenna cable in a residential complex from the stairwell into apartments (where almost exclusively only one antenna cable is available).
The adjacent picture 1 shows an installation for an eleven party house. After the four satellite IF levels, which come from a universal Quattro LNB, have been pre-amplified, they are fed into a satellite switch. In addition to the satellite IF levels, terrestrial signals (e.g. DVB-T and VHF ) can also be added. This is followed by a separate SCR matrix for each apartment, in this case for up to four single receivers or two twin receivers per apartment. First, this has the advantage that apartments cannot interfere with one another. If a receiver is set incorrectly, all other receivers on the same line are affected. Second, the lowest channels can always be used for each apartment. In the system shown, the lowest channel starts at 1400 MHz (other manufacturers sometimes work from 1076 MHz). With up to eight devices on one line, the last channel would be 2096 MHz, which can lead to level problems with existing cabling with older cables, as higher frequencies experience greater attenuation. In this example, after three matrices, one amplifier each follows. The last element in each string is an SCR matrix with an integrated power supply unit that supplies the two strings with power.
Due to the more complex structure of the system, careful preparation, the use of high-quality components and compliance with the level and attenuation values during all steps are particularly important.
Fig. 2 shows a unicable processing system for a total of 21 parties or residential units including a completed equipotential bonding (regulation for multi- apartment installation or if the antenna receiving system was installed in the lightning protection area ). From the two "large" components (Jultec JPS0508-3) three Unicable implementations (for operating three receivers) are transmitted to eight apartments, the two "small" components (Jultec JPS0502-6) transmit six to two apartments each Implementations (for the operation of six receivers). An extra room was supplied via “legacy output”. These switches are combined or connected by means of a cascade connection, i. H. the four trunks or bands and the terrestrial input (CATV) are looped through from switch to switch.
The switches themselves do not require a power supply, they are supplied via the receiver switching voltages. The LNB power supply was carried out via a preamplifier connected upstream of the switches. These switches have an AGC control (Auto Gain Control) from an Entropic Unicable chipset, which automatically adjusts the signal level at the input, i. H. comes z. B. too little signal from the LNB, the level is automatically adjusted as far as possible so that the switch can process it as best as possible, or if there is too much signal, also known as "overload", the level is lowered so that the switch does not to override. The outputs are partially provided with cable routes of over 60 m to the apartment distribution, the apartment distribution then splits the signal within the apartments further to the set antenna sockets. A VHF, DVB-T antenna and the digital radio DAB + were fed in via the terrestrial input and thus also transmitted to every connection point.
Since 2010, JULTEC has also been offering Unicable distribution components with its JRS switch series that no longer require a power supply (receiver-powered / receiver-powered). This is made available to the switches via the receiver switching voltage . This is particularly suitable when planning systems where no power supply is available at the multi-switch location, or for systems in multi-party houses, as this means that no offsetting for the electricity cost allocation per party has to be made (if no shared electricity connection could be used).
Alternatives
An alternative to the Unicable solution is the satellite block distribution using conventional multi-switches or the technically limited single-cable systems .
JESS (Jultec Enhanced Stacking System) is a downward-compatible expansion of the Unicable protocol by the German company Jultec, which allows up to 32 receivers on one line and can control up to 64 satellite positions. The protocol description is published on Jultec's homepage and became a European standard in 2013 under EN 50607 . However, the names differ here too. For example, Kathrein uses the name "SCD2", Panasonic uses the name "Einkabel 2.0" and Inverto / FTA uses the name "Unicable 2". It should be noted that Inverto does not use a standardized method of counting the user band IDs, which can lead to confusion for users and incorrectly configured receiving devices.
The so-called Sat-over-IP technology can be mentioned as an alternative . It enables the satellite signals to be converted into local networks . This means that up to four free-to-air TV channels are available on IPTV- enabled devices.
Norms
- DIN EN 50494: Signal distribution of satellite signals via a single coaxial cable distribution network, German version of EN 50494: 2007, edition 2008-02
- DIN EN 50607: JESS (Jultec Enhanced Stacking System) single-cable system, successor standard to EN 50494: 2013/2014
swell
- ↑ EN 50494 ("SCR / Unicable") in VDR: Changelog Version 1.7.22
- ↑ EN 50607 ("SCR / JESS") in VDR: Changelog Version 2.1.18
- ↑ DIGITAL TELEVISION 11/2012. Publishing announcement. Auerbach Verlag und Infodienste GmbH, accessed on March 26, 2013 .
- ↑ JESS (Jultec Enhanced Stacking System). Glossary entry. Jultec GmbH, accessed on March 26, 2013 .
- ^ New tuning format "JESS" (JULTEC Enhanced Stacking System) for CSS systems. (PDF; 81 kB) Specification. Jultec GmbH, accessed on March 26, 2013 .
- ↑ SAT-IP: Easily receive satellite TV on tablets, smartphones and computers. ASTRA Deutschland GmbH, July 12, 2012, accessed on March 26, 2013 .