SIST EN 50494:2008

SLOVENSKI STANDARD
01-januar-2008
Distribucija satelitskega signala po enojnem koaksialnem kablu v
enostanovanjskih inštalacijah
Satellite signal distribution over a single coaxial cable in single dwelling installations
Signalverteilung von Satellitensignalen über ein einziges koaxiales Kabelverteilnetz
Distribution de signaux satellites sur un seul câble coaxial dans les résidences
individuelles
Ta slovenski standard je istoveten z: EN 50494:2007
ICS:
33.060.30 Radiorelejni in fiksni satelitski Radio relay and fixed satellite
komunikacijski sistemi communications systems
33.120.10 Koaksialni kabli. Valovodi Coaxial cables. Waveguides
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 50494
NORME EUROPÉENNE
October 2007
EUROPÄISCHE NORM
ICS 33.060.30; 33.160.01
English version
Satellite signal distribution over a single coaxial cable
in single dwelling installations

Distribution de signaux satellites  Signalverteilung von Satellitensignalen
sur un seul câble coaxial über ein einziges koaxiales
dans les résidences individuelles Kabelverteilnetz

This European Standard was approved by CENELEC on 2007-03-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in two official versions (English, German). A version in any other language made
by translation under the responsibility of a CENELEC member into its own language and notified to the Central
Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2007 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50494:2007 E
Foreword
This European Standard was prepared by the Technical Committee CENELEC TC 206, Consumer
equipment for entertainment and information and related sub-systems.
The text of the draft was submitted to the Unique Acceptance Procedure and was approved by
CENELEC as EN 50494 on 2007-03-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2008-05-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2010-03-01
__________
- 3 - EN 50494:2007
Contents
Introduction.5
1 Scope .5
2 Normative references.6
3 Acronyms and definitions .6
3.1 Acronyms.6
3.2 Definitions.7
4 System architecture .7
5 SCIF control signals. 10
5.1 DC levels .10
5.2 Method of the data bit signalling. 11
5.3 Structure of the DiSEqC message in the single coaxial cable system . 11
6 Structure and format of the DiSEqC messages . 12
6.1 DiSEqC addressesl. 12
6.2 Normal operation. 12
6.2.1 ODU_Channel_change . 13
6.2.2 ODU_PowerOFF . 14
6.3 Special modes. 14
6.3.1 Installation, SCIF parameters recognition . 14
6.3.2 ODU_UBxSignal_ON. 16
6.3.3 ODU_Config . 16
6.3.4 ODU_LoFreq. 17
7 Look-up tables and conventions. 17
7.1 UB slots numbering . 17
7.2 Input banks numbering . 18
7.3 Config_Nb table . 18
7.4 LoFreq table. 19
8 Traffic collision management rules. 20
9 Optional extension of the single cable distribution to the multi-dwelling installations . 22
9.1 Extension for multi-dwelling installations.22
9.2 Extensions for structure and format of the DiSEqC messages . 23
9.3 Specific commands for installation (see 6.3.1 to 6.3.4) . 23
9.4 Installation with manual entry of the system parameters, PIN code handling . 24
9.5 SDU and MDU compatibility rules . 25
Annex A (informative) Implementation guidelines . 26
A.1 Installation impedance .26
A.2 Installation: signal reflection and returned loss. 26
A.3 Power supply of the SCIF. 27
A.4 Tuning word calculation, software recommendations . 28
A.5 RF scanning, RF tone recognition, SCIF parameter recognition. 29

Figures
Figure 1 – General architecture of the single cable distribution .6
Figure 2 – General system operation and UB slot frequency mapping .8
Figure 3 – Installation example, system with two UB slots .9
Figure 4 – Installation example implementing a monobloc LNB with four UB slots .9
Figure 5 – Example of a switcher with two outputs serving six UB slots each . 10
Figure 6 – Outlines of the signal sent by the receiver . 11
Figure 7 – Bit signalling according to DiSEqC format . 11
Figure 8 – DiSEqC command structure . 12
Figure 9 – Example of signal structure delivered by the SCIF featuring four UB slots after
an ODU_UBxSignal_ON. 16
Figure 10 – DiSEqC command collision between two receivers and recovery system . 21
Figure 11 – Pseudo random delay generation for the repeat operation . 22
Figure 12 – Example of signal spectrum delivered by a SCIF (with MDU option) after an
ODU_UbxSignal_ON (or an ODU_UbxSignal_ON_MDU ) command . 24
Figure A.1 – Solution for masking the impedance of the installation during the DiSEqC
commands. 26
Figure A.2 – Implementation of an external power supply . 27
Figure A.3 – Example of a RF spectrum found after an ODU_UBxSignal_ON. 29
Tables
Table 1 – Automatic installation sub-functions. 15
Table 2 – UB slot numbering . 17
Table 3 – Input bank numbering . 18
Table 4 – Config_Nb table . 18
Table 5 – Local oscillation (LO) table in Standard RF (Conventional RF ) . 19
Table 6 – Local oscillation (LO) table in Wide band RF . 19
Table 7 – Expected system behaviour . 25

- 5 - EN 50494:2007
Introduction
In EN 61319-1:1995 the interfaces for the control and command of the devices associated with the
satellite receivers are described in the following clauses:
– Clause 4: Interfaces requirements for polarizer and polar switchers;
– Clause 5: Interfaces requirements for low-noise block converters (LNB).
In these clauses, analogue techniques are described for controlling the LNB and polar switchers.
In EN 61319-1/A11, the “Digital Satellite Equipment Control Bus” (called DiSEqC) is introduced as a
single method of communication between the satellite and the peripheral equipment, using only the
existing coaxial cables.
The purpose of this document is to introduce a complete system for distributing via a single coaxial
cable signals issued from different bands and polarizations to several satellite receivers.
The presented system is intended for single dwelling installation (individual subscriber installations)
but in Clause 9 of this document there is also described an optional extension for multiple dwelling
installations.
The presented system is scaled for installations in which the number of demodulators is limited to a
maximum number of 8 units per output of the Single Cable Interface (hereafter referred to as SCIF)
device.
1 Scope
This European Standard describes:
– the system physical structure;
– the system control signals, which implement an extension of the DiSEqC set of commands
described in the DiSEqC bus functional specification;
– the definition of identified configurations;
– management of the potential collisions in the control signals traffic.
Figure 1 illustrates the physical system configuration considered in this European Standard.
Several satellite signal demodulators can receive signals from any of the input signal banks of the LNB
or the switch; the signals selected by the demodulators (or receivers) are transported via a single
cable to these demodulators (receiver 1, receiver 2, receiver N).
To achieve these single cable distributions, the Single Cable Interface (SCIF) (likely embedded in a
LNB or a Switch) features some specific functions and characteristics.

SSIINGNGLLEE C CAABLBLEE
ReceiReceivveer 1r 1
ININTTEERRFFAACCEE: : SCIF
SCIF
BanBankk 1 1
Receiver 2
Receiver 2
LLNNB B
Power
Power
oror
BanBankk 2 2
splitter
splitter
SWSWIITTCCHH
BanBankk M M
Receiver N
Receiver N
Single cable
Single cable
connection
connection
AA re receiver maceiver mayy in integrtegratate see sevveeral deral demmoodduulalators tors

Figure 1 – General architecture of the single cable distribution
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
EN 50083-4 Cable networks for television signals, sound signals and interactive services –
Part 4: Passive wideband equipment for coaxial cable networks
EN 61319-1:1996 Interconnections of satellite receiving equipment – Part 1: Europe
+ A11:1999 (IEC 61319-1:1995)
EN ISO/IEC 13818-1 Information technology – Generic coding of moving pictures and associated
audio information – Part 1: Systems (ISO/IEC 13818-1)
TM
“DiSEqC ” Bus Functional Specification Version 4.2, February 25, 1998
http://www.eutelsat.com/satellites/4_5_5.html
3 Acronyms and definitions
3.1 Acronyms
CW Continuous Wave
DiSEqC Digital Satellite Equipment Control
LNB Low Noise Block
LUT Look-up Table
MDU Multiple Dwelling Unit
MSB Most significant bit
ODU Out-door Unit
PCR Program clock reference
PWK Pulse Width Keying
SCIF Single Cable Interface
- 7 - EN 50494:2007
SDU Single Dwelling Unit
UB User Band
3.2 Definitions
3.2.1
bank
group of contiguous channels belonging to a polarization and or a band
3.2.2
channel
radio frequency transponder signal
3.2.3
demodulator
electronic device integrating at least a tuner and a demodulator
3.2.4
receiver
electronic equipment embedded in a cabinet and integrating all functions for demodulating and
decoding the received satellite signals, a receiver may integrate several demodulators
3.2.5
universal LNB
LNB with the following characteristics: operation in the Ku bands (10,7 GHz ! 12,75 GHz); local
oscillator frequency is 9,75 GHz for signal frequencies lower than 11,7 GHz and local oscillator
frequency is 10,6 GHz otherwise
4 System architecture
In the single coaxial cable distribution system, the bandwidth of the shared coaxial cable is divided into
slots (user band: UB). The number of slots Nb_ub varies from one application to another; the number
of slots Nb_ub is a characteristic of the SCIF.
The system defined in this standard limits the number of UB slots to 8 (eight) per output of the SCIF.
Each demodulator connected to the single coaxial cable distribution is allocated a UB slot; this
allocation is done either in static or other modes.
– Static mode: the allocation of the UB slot is done during the installation of the satellite receiver.
Only the static mode is considered in this document.
– Other modes are not described in this document but could be considered in a further release or
annex of this document.
After the slot allocation, the tuner of the receiver operates at a single frequency (centre of the slot UB).
To select a desired channel (frequency Fd) the demodulator sends a SCIF control signal that provides
the following information:
– select the bank (band, feed, polarization) that carries the desired signal.
– select the frequency (Fd) of the desired signal.
– designate the UB slot on which the desired signal is expected.
Figure 2 illustrates the frequency mapping for such a single coaxial cable system.

Figures 3, 4, and 5 illustrate various examples for implementing the single cable distribution system
(other application scenarios are possible).
– Figure 3: a single coaxial cable distribution is implemented between a LNB and two demodulators.
– Figure 4: a single coaxial cable distribution is implemented between a double feed LNB and a set
of 4 demodulators.
– Figure 5: In an installation that shall serve more than 8 demodulators, a SCIF device with several
outputs (Out) is implemented; each output can serve a maximum number of demodulators
(Nb_ub). In the illustrated example, there are 2 outputs, each output can serve up to
6 demodulators, the output Out 2 could serve two additional demodulators before reaching the
limit of the installed hardware.
SINGLE CABLE
SINGLE CABLE
IINNTTEERRFFAACCEE  SSCCIFIF
Single cable
Single cable
Receiver 1
Receiver 1
connectionconnection
BBaanknk 1 1
LNB
LNB
PoPowweerr
ReRecceiveiveerr 2 2
or
or
Bank 2
Bank 2
spsplliitttteerr
SWITCH
SWITCH
BanBankk M M
RReecceeiviver Ner N
FdFd33
BBaanknk 1 1
FdFd22
UIUIFF Bank 2
Bank 2
iinnputputss
Fd1Fd1
BBaanknk M M
frfreequencquencyy
UIUIFF
outoutputput
UBUB__22
UBUB__11 UBUB__33 UBUB__TT
T=T= Nb_ Nb_uubb
Figure 2 – General system operation and UB slot frequency mapping

- 9 - EN 50494:2007
BaBannkk 1 1
PowPoweerr
splitter
splitter
BaBannkk 2 2
RReceeceiivveerr 1 1
SCIF
SCIF
BaBannkk 3 3
RReceeceiivveerr 2 2
BaBannkk 4 4
Number of banks = Nb_B = 4
Number of banks = Nb_B = 4
Number of user slots = Nb_ub = 2
Number of user slots = Nb_ub = 2

Figure 3 – Installation example, system with two UB slots
Bank 1
Bank 1
SSaatteelllliittee
AA
BaBannkk 2 2
RReceeceiivveerr 1 1
PoPowweerr
BaBannkk 3 3
spsplilitttterer
RReceeceiivveerr 2 2
BaBannkk 4 4
SCSCIFIF
Bank 5
Bank 5
SSaatteelllitlitee
BB RReceeceiivveerr 3 3
BaBannkk 6 6
RReceeceiivveerr 4 4
BaBannkk 7 7
BaBannkk 8 8
NNuummbberer ooff b baannks ks == N Nbb_B_B = = 88
NNuummbeberr o off ususeerr ssllootts =s = N Nbb_u_ubb = = 44

Figure 4 – Installation example implementing a monobloc LNB with four UB slots

Receiver 1
Receiver 1
RReeceiceiverver 2 2
RReeceiceiverver 3 3
OuOut 1t 1
SCSCIIFF
(Nb_ub=6)
(Nb_ub=6)
RReeceiceiverver 4 4
RReeceiceiverver 5 5
RReeceiceiverver 6 6
Bank 1
Bank 1
Bank 2
Bank 2
RReeceiceiverver 1 1
SCSCIIFF
Out 2
Out 2
BaBannkk 3 3 (Nb_ub=6)
(Nb_ub=6)
RReeceiceiverver 2 2
Bank 4
Bank 4 Power
Power
DDeemodulmodulaattor 3or 3
splitters
splitters
DDeemodulmodulaattor 4or 4
Example : system integrating 2 SCIF
Example : system integrating 2 SCIF
On out 2, Out of 6 UB resources 4 UB
On out 2, Out of 6 UB resources 4 UB
RReceieceiverver 3 3
slots are actually used.
slots are actually used.
Figure 5 – Example of a switcher with two outputs serving six UB slots each
5 SCIF control signals
5.1 DC levels
In a single coaxial cable distribution system, all controls issued by the receivers (demodulators) are
done according to the DiSEqC format.
The single coaxial cable distribution system is not backwards compatible with the former 13/18 V
control associated with a continuous 22 kHz tone. The single coaxial cable distribution system is also
not backwards compatible with the tone burst signalling.
In single coaxial cable distribution systems, the signal-sending receiver generates a high DC level
upon which the DiSEqC control signals are added. After sending the DiSEqC control signal the
receiver returns to an idle mode in which it generates a low DC level onto the single cable distribution
system (refer to Figure 6). With reference to EN 61319-1, the low and high DC level shall have the
following limits on the signal-sending- receiver side:
– LOW _DC value: 12,5 V to 14 V
– HIGH_ DC value: 17 V to 19 V
The delays (td & ta) shall have the following limits:
– td > 4 ms and td < 22 ms
min max
– ta > 2 ms and ta < 60 ms
min max
- 11 - EN 50494:2007
DD iiSS EE qqCC c c oo mm mm anan dsds ≈≈ 67.67.5 m5 m ss
18V
18V
tata
tdtd
13V13V
Figure 6 – Outlines of the signal sent by the receiver
The hardware of the communication bus has to be realized according to the DiSEqC bus functional
specification. Some additional care shall be taken to ensure an appropriate impedance of the
installation during the DiSEqC sequences. In Annex A implementations are suggested.
5.2 Method of the data bit signalling
DiSEqC uses base-band timings of 500 µs (+/- 100 µs) for a one-third-bit PWK coded signal on a
nominal 22 kHz (+/- 4 kHz) carrier. See DiSEqC bus functional specification and
EN 61319/1996/A11:1999.
Figure 7 shows the 22 KHz time envelop for each bit transmitted, with nominally 22 cycles for a bit “0”
and 11 cycles for a bit “1”.
““0”0” Da Dattaa b biitt ““1”1” D Daattaa bbiitt
0.0.6565VppVpp
TyTyp.p.
0.5 ms
0.5 ms
1 ms
1 ms 0.0.5 m5 mss 1 m1 mss
2222 cyc cyclesles 11 c11 cyclycleess 1111 cyc cyclesles 2222 cyc cycleless

Figure 7 – Bit signalling according to DiSEqC format
5.3 Structure of the DiSEqC message in the single coaxial cable system
The structure of the message sent by the receiver to the SCIF is described in Figure 8.
Each message contains 5 bytes of 8 data bits each, an odd parity bit is added to each byte. A byte has
a typical duration of 13,5 ms; the 5 bytes message lasts 67,5 ms.

The length of the DiSEqC control sequence is limited to 5 bytes for minimizing the traffic and
consequently the risk of collisions.
67.5 ms typically
67.5 ms typically
FrFraammiinngg PP AdAddrdreessss PP CCoommammanndd PP DADATTAA 1 1 PP DADATTAA 2 2 PP

Figure 8 – DiSEqC command structure
IMPORTANT NOTE 1: For compatibility reasons concerning MDU extension (see Clause 9), SCIF
devices without MDU option are not required to detect but have to tolerate other command structures
(concerning command length and sequence of different bytes).
IMPORTANT NOTE 2: The SCIF devices are not required to detect but have to tolerate other
command structures (e.g.: tone burst control) that would follow the 5 bytes command structure
described in this section; in this case a minimum duration higher than the above specified “ta“ shall be
respected between the SCIF control command and these added commands.
6 Structure and format of the DiSEqC messages
6.1 DiSEqC addressesl
FRAMING
In order to minimize the overall DiSEqC signal traffic, the single coaxial cable distribution commands
only use the framing word E0h (command from master (receiver), no reply required, first
transmission).
ADDRESS: the following addresses are recognized by the SCIF: 00h, 10h, and 11h.
COMMAND: the following command values are implemented: 5Ah and 5Bh.
All DiSEqC sequences used in the single coaxial cable distribution include two data bytes: Data 1 and
Data 2.
6.2 Normal operation
This subclause defines the DiSEqC control sequences used during normal operation of the system;
the control signals of this subclause implement the command value: 5Ah.
Two control sequences are defined during normal operation:
– ODU_Channel_change;
– ODU_PowerOFF.
The support of the two above commands is mandatory for all SCIF compatible equipment.

- 13 - EN 50494:2007
6.2.1 ODU_Channel_change
ODU_Channel_change: the receiver sends this command when tuning to a (new) channel is
required.
ODU_Channel_change format:
E0h 00h or 10h or 11h 5Ah Data 1 Data 2
Data 1 format
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
UB [2:0] Bank [2:0] T [9:8]
Data 2 format
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
T [7:0]
– UB [2:0] bits select the slot on which the desired signal is expected (Table 2)
– Bank [2:0] bits select the signal bank which carries the desired channel (Table 3)
– The T[.] word is the tuning word calculated by the receiver.
T = round ( ( abs( F – F ) + F ) / S ) – 350
T O UB
where
• T = decimal value of the tuning word T[.]
• F = transponder frequency in MHz (e.g. 12 515,25).
T
• F = Oscillator frequency of the 1st conversion stage of the LNB (in switch application,
O
F is also the oscillator frequency of the 1st conversion stage of the LNB which
O
generates the signal of the desired bank).
• F = desired UB slot centre frequency in MHz (e.g. 1 632).
UB
• S = coding step size. Actual value 4 MHz (high step size is needed for minimizing the
length of the T[.] word).
• 350 = constant value used to further compress the T[.] word.
IMPORTANT NOTE: Since the tuning word is entirely calculated by the demodulator, the rounding
effects induced by the coding step size can be fully predicted and then fully compensated. During the
channel acquisition the frequency search range remains unchanged compared with conventional
solutions. In A.4, some explanation and suggestions are given to better exploit the calculated tuning
word.
6.2.2 ODU_PowerOFF
ODU_PowerOFF: the receiver sends this command as soon as the corresponding demodulator is
turned-OFF, in doing so both power is saved and an UB resource can be released.
E0h 00h or 10h or 11h 5Ah Data 1 Data 2 =00
Data 1
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
UB [2:0] 0 0 0 0 0
The UB [2:0] bits select the UB slot that shall be turned OFF.
6.3 Special modes
This subclause defines the DiSEqC control sequence used during special modes of the system; the
control signals of this subclause use the command value: 5Bh.
A wide variety of special operation modes can be foreseen:
– installation mode;
– operation mode compatible with professional installation equipment;
– dynamic allocation of the UB slots, etc.
This document only deals with the installation mode; further extension could integrate functions
required by other special modes.
6.3.1 Installation, SCIF parameters recognition
To operate in a single coaxial cable operation, the receivers need to identify several parameters of the
SCIF to calculate the tuning word and to position the tuner at the right frequency.
The parameters absolutely needed by the receiver to select desired channels are:
F Local oscillator frequency of the LNB or of the LNB generating a bank.
O
F The centre frequency of the UB slot allocated to the receiver.
UB
S Coding step size of the channel, value actually frozen at 4 MHz
6.3.1.1 Automatic installation with the RF tone signalling method
This subclause describes the procedure and the DiSEqC control sequences required for implementing
an automatic recognition of the parameters of the SCIF.
Principle:
By means of specific DiSEqC commands each receiver can interrogate the database of the SCIF
device. The “interrogation” messages carry three pieces of information:
– the UB slot on which the answer is expected (UB [2:0]);
– the type of information that is checked (Sub-function [4:0]);
– a number that is compared with a value stored in the database of the SCIF: LUT [7:0].

- 15 - EN 50494:2007
The SCIF device answers to the request by generating a RF tone (CW).
– The answer is “YES” when the information in Data 2 matches with the similar data stored in the
database of the SCIF. In case of “YES” answer, the frequency of the RF tone matches with the
centre frequency of the UB slot.
– The answer is NO as long as the Data 2 value does not match with the value stored in the SCIF
database. In case of “NO” answer, the frequency of the RF tone is 20 MHz above the UB centre
frequency. As long as the answer is NO, the receiver increments its pointer in the look-up table of
interest.
In this European Standard three such system parameter recognition commands are defined:
– ODU_UBxSignal_ON;
– ODU_Config;
– ODU_LoFreq.
These commands respect the following format:
E0h 00h or 10h or 11h 5Bh Data 1 Data 2
Data 1
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
UB [2:0] Sub function [4:0]
Data 2
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
LUT [7:0]
The list of the commands required in the automatic installation with the RF tone signalling method is
given in Table 1.
Table 1
...