SIST ETS 300 421 E1:2003
(Main)Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for 11/12 GHz satellite services
- Abstract
Baseline System for modulation and channel coding for satellite digital multi-programme TV/HDTV services to be used for satellite digital TV for primary and secondary distribution in FSS and BSS bands The Baseline System is intended to provide Direct-to-Home (DTH) services for consumer Integrated Receiver Decoders (IRDs) as well as collective antenna systems (SMATV) and cable television head-end stations with a likelihood of remodulation. The Baseline System uses QPSK modulation and concatenated error protection strategy based on a convolutional code and a shortened Reed-Solomon code. The Baseline System is suitable for use on different satellite transponder bandwidths. Compatibility with MPEG-2 coded TV services, with a transmission structure synchronous with the packet multiplex, is provided. The multiplex flexibility allows the use of transmission capacity for a variety of TV service configurations, including sound and data services. All service components are time multiplexed (TDM) on a single digital carrier.
- Status
- Published
- Publication Date
- 30-Nov-2003
- Current Stage
- 6060 - National Implementation/Publication (Adopted Project)
- Start Date
- 01-Dec-2003
- Due Date
- 01-Dec-2003
- Completion Date
- 01-Dec-2003
- Mandate
- T-304
SIST ETS 300 421 E1:2003 is the Slovenian adoption of ETS 300 421 Edition 1, published by SIST. It specifies the DVB framing structure, channel coding and modulation for 11/12 GHz satellite services, aimed at satellite digital multi-programme TV/HDTV distribution. The document is written for equipment designers, network operators, integrators and buyers who need a common signal format for interoperable satellite transmission equipment.
What does SIST ETS 300 421 E1:2003 specify?
SIST ETS 300 421 E1:2003 specifies the transmission system for satellite digital TV services in the Fixed Satellite Service (FSS) and Broadcast Satellite Service (BSS) bands. It focuses on the signal that is transmitted, the processing on the modulator side, and the performance targets that equipment should meet in practice.
The scope covers Direct-To-Home (DTH) services for consumer Integrated Receiver Decoders (IRD), collective antenna systems (SMATV) and cable television head-end stations where remodulation may be used. The receive side is described only to the extent needed for system compatibility.
| Annex | What it covers |
|---|---|
| Annex A | Signal spectrum at the modulator output |
| Annex B | Conceptual System description |
| Annex C | Examples of bit rates versus transponder bandwidth |
| Annex D | Examples of possible use of the System |
| Annex E | Bibliography |
The main body is organized into scope, normative references, symbols and abbreviations, transmission system, and error performance requirements. Clause 4 contains the technical method, while clause 5 states the performance target.
What are the key requirements of SIST ETS 300 421 E1:2003?
Transmission chain and system purpose
Clause 4.1 defines the System as the functional block that adapts baseband television signals from the output of the Moving Pictures Experts Group-2 (MPEG-2) transport multiplexer to the satellite channel. The sequence is fixed: transport multiplex adaptation and randomization, outer Reed-Solomon (RS) coding, convolutional interleaving, inner punctured convolutional coding, baseband shaping and modulation.
In practice, this means equipment from different manufacturers must process the stream in the same order so that the transmitted signal can be received and decoded consistently.
Clause 4.1 also states that the System uses Quaternary Phase Shift Keying (QPSK) and concatenated error protection based on a convolutional code and a shortened RS code. This choice reflects the power-limited nature of DTH satellite links, where robustness matters more than spectrum efficiency.
Transponder fit and interfaces
Clause 4.2 requires the symbol rate to be matched to the satellite transponder characteristics. Annex C gives example capacities for different bandwidths, which is useful when planning capacity, selecting a transponder and balancing throughput against degradation.
Clause 4.3 fixes the system interfaces. The transmit station takes MPEG-2 transport input and outputs an intermediate-frequency signal for RF devices, while the receive installation outputs MPEG-2 transport to the demultiplexer and takes input from RF devices. This matters because it defines where the standard ends and where external equipment connects.
Randomization, RS coding and interleaving
Clause 4.4.1 requires transport multiplex adaptation and randomization for energy dispersal. The stream is organized in fixed-length MPEG-2 transport packets, and the sync byte of the first packet in each group of eight is inverted to support descrambling and synchronization. The randomizer is active even when the input is absent or non-compliant, which helps avoid transmission of an unmodulated carrier.
Clause 4.4.2 specifies RS(204,188, T=8) as a shortened RS code applied to each randomized transport packet. It also requires convolutional interleaving with depth I = 12. In practical terms, this spreads burst errors so the outer RS decoder can correct them more effectively.
Inner code and modulation
Clause 4.4.3 defines a family of punctured convolutional codes based on a rate 1/2 code with constraint length K = 7. The permitted code rates are 1/2, 2/3, 3/4, 5/6 and 7/8. This allows the operator to choose more protection or more payload, depending on the service and link budget.
Clause 4.5 requires conventional Gray-coded QPSK with absolute mapping and no differential coding. The baseband shaping uses a square-root raised cosine filter with a roll-off factor of 0.35. Annex A gives the output spectrum mask and group-delay template, which are the reference points for modulator design and test.
Error performance target
Clause 5 sets the IF-loop error performance requirement as BER versus E_b/N_0 for each inner code rate. The standard links these values to a Quasi-Error-Free (QEF) target, meaning less than one uncorrected error event per hour at the MPEG-2 demultiplexer input. For users, this is the practical acceptance target for receiver and modem performance.
What terms does SIST ETS 300 421 E1:2003 define?
- Direct-To-Home (DTH) - satellite television service intended for reception by end users with consumer equipment.
- Integrated Receiver Decoder (IRD) - the consumer receiver/decoder used to receive and process satellite TV services.
- Satellite Master Antenna Television (SMATV) - a collective antenna distribution system serving multiple users from shared satellite reception equipment.
- Fixed Satellite Service (FSS) - the satellite service band used for fixed communication links in this System.
- Broadcast Satellite Service (BSS) - the satellite broadcast band used for this System.
- Quasi-Error-Free (QEF) - the quality target used in the document for very low visible error occurrence after decoding.
- Time Division Multiplex (TDM) - the method used to place all service components on a single digital carrier.
- Forward Error Correction (FEC) - the error-protection approach used to recover data after transmission impairments.
Who uses SIST ETS 300 421 E1:2003?
SIST ETS 300 421 E1:2003 is used by satellite broadcast engineers, modem designers and system integrators who need a common DVB satellite transmission format. It is also relevant to manufacturers of modulators, demodulators, IRDs, SMATV equipment and cable head-end stations.
Operators use it when planning transponder use, selecting code rates, checking BER performance and verifying compatibility with MPEG-2 transport streams. Quality managers and buyers use it to compare equipment against a defined satellite interface and performance target.
What changed in SIST ETS 300 421 E1:2003 from the previous edition?
SIST ETS 300 421 E1:2003 is identical to ETS 300 421 Edition 1. The document history in the standard records the first edition and a later PDF conversion.
Which standards are used with SIST ETS 300 421 E1:2003?
- ISO/IEC DIS 13818-1 - provides the MPEG-2 transport coding and multiplex structure that this System adapts.
- Forney, G.D., IEEE Trans. Comm. Tech., COM-19 - supports the convolutional interleaving approach described in the document.
- Intelsat Earth Station Standards (IESS) No. 308 - provides the basis for the spectrum-mask template in Annex A.
- ETS 300 429 - is cited in the scope as a related ETS for remodulation and cable-distribution context.
What does the SIST ETS 300 421 E1:2003 document contain?
The document includes a functional block diagram of the transmission chain, a randomizer schematic, framing diagrams, an interleaver/de-interleaver concept, and a QPSK constellation figure. It also contains the punctured-code definition, interface table, and the BER/E_b/N_0 performance table used for conformance checks.
Annex A provides a spectrum mask and group-delay mask for the modulator output, together with defined points on the template. Annex C gives example bandwidth and bit-rate calculations for satellite transponders, including the effect of transponder filtering and amplifier back-off. Annex D shows example service configurations and a worked connection example to a terrestrial PDH network.
For implementation work, the document is useful as a design reference for modulators, receive chains and link budgets. For verification, it gives the signal shape, coding structure and performance targets needed to test whether an implementation matches the specified DVB satellite baseline.
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Frequently Asked Questions
SIST ETS 300 421 E1:2003 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for 11/12 GHz satellite services". This standard covers: Baseline System for modulation and channel coding for satellite digital multi-programme TV/HDTV services to be used for satellite digital TV for primary and secondary distribution in FSS and BSS bands The Baseline System is intended to provide Direct-to-Home (DTH) services for consumer Integrated Receiver Decoders (IRDs) as well as collective antenna systems (SMATV) and cable television head-end stations with a likelihood of remodulation. The Baseline System uses QPSK modulation and concatenated error protection strategy based on a convolutional code and a shortened Reed-Solomon code. The Baseline System is suitable for use on different satellite transponder bandwidths. Compatibility with MPEG-2 coded TV services, with a transmission structure synchronous with the packet multiplex, is provided. The multiplex flexibility allows the use of transmission capacity for a variety of TV service configurations, including sound and data services. All service components are time multiplexed (TDM) on a single digital carrier.
Baseline System for modulation and channel coding for satellite digital multi-programme TV/HDTV services to be used for satellite digital TV for primary and secondary distribution in FSS and BSS bands The Baseline System is intended to provide Direct-to-Home (DTH) services for consumer Integrated Receiver Decoders (IRDs) as well as collective antenna systems (SMATV) and cable television head-end stations with a likelihood of remodulation. The Baseline System uses QPSK modulation and concatenated error protection strategy based on a convolutional code and a shortened Reed-Solomon code. The Baseline System is suitable for use on different satellite transponder bandwidths. Compatibility with MPEG-2 coded TV services, with a transmission structure synchronous with the packet multiplex, is provided. The multiplex flexibility allows the use of transmission capacity for a variety of TV service configurations, including sound and data services. All service components are time multiplexed (TDM) on a single digital carrier.
SIST ETS 300 421 E1:2003 is classified under the following ICS (International Classification for Standards) categories: 33.060.30 - Radio relay and fixed satellite communications systems; 33.170 - Television and radio broadcasting. The ICS classification helps identify the subject area and facilitates finding related standards.
SIST ETS 300 421 E1:2003 is associated with the following European legislation: Standardization Mandates: T-304. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
SIST ETS 300 421 E1:2003 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-december-2003
Sistemi digitalne radiodifuzije za televizijske, zvokovne in podatkovne storitve –
Struktura okvirov, kodiranje kanalov in modulacija za satelitske storitve na 11/12
GHz
Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for
11/12 GHz satellite services
Ta slovenski standard je istoveten z: ETS 300 421 Edition 1
ICS:
33.060.30 Radiorelejni in fiksni satelitski Radio relay and fixed satellite
komunikacijski sistemi communications systems
33.170 Televizijska in radijska Television and radio
difuzija broadcasting
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN ETS 300 421
TELECOMMUNICATION December 1994
STANDARD
Source: EBU/ETSI JTC Reference: DE/JTC-DVB-6
ICS: 33.160.20, 33.060.140
Digital television broadcasting by satellite, modulation, channel coding
Key words:
European B roadcasting Union Union Européenne de Radio-Télévision
EBU
UER
Digital broadcasting systems for television,
sound and data services;
Framing structure, channel coding and modulation
for 11/12 GHz satellite services
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
F-06921 Sophia Antipolis CEDEX - FRANCE
Postal address:
650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
Office address:
c=fr, a=atlas, p=etsi, s=secretariat - secretariat@etsi.fr
X.400: Internet:
Tel.: +33 92 94 42 00 - Fax: +33 93 65 47 16
Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1994. All rights reserved.
© European Broadcasting Union 1995. . All rights reserved.
New presentation - see History box
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ETS 300 421: December 1994
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.
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ETS 300 421: December 1994
Contents
Foreword .5
1 Scope .7
2 Normative references.7
3 Symbols and abbreviations .8
3.1 Symbols .8
3.2 Abbreviations .8
4 Transmission system .9
4.1 System definition.9
4.2 Adaptation to satellite transponder characteristics .10
4.3 Interfacing .10
4.4 Channel coding.10
4.4.1 Transport multiplex adaptation and randomization for energy dispersal.10
4.4.2 Outer coding (RS), interleaving and framing.11
4.4.3 Inner coding (convolutional) .12
4.5 Baseband shaping and modulation.13
5 Error performance requirements.14
Annex A (normative): Signal spectrum at the modulator output.15
Annex B (informative): Conceptual System description.17
Annex C (informative): Examples of bit rates versus transponder bandwidth.19
Annex D (informative): Examples of possible use of the System.22
Annex E (informative): Bibliography.23
History.24
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ETS 300 421: December 1994
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ETS 300 421: December 1994
Foreword
This European Telecommunication Standard (ETS) has been produced under the authority of the Joint
Technical Committee (JTC) of the European Broadcasting Union (EBU) and the European
Telecommunications Standards Institute (ETSI).
NOTE: The EBU/ETSI JTC was established in 1990 to co-ordinate the drafting of ETSs in the
specific field of radio, television and data broadcasting.
The EBU is a professional association of broadcasting organisations whose work
includes the co-ordination of its Members' activities in the technical, legal, programme-
making and programme-exchange domains. The EBU has Active Members in about
60 countries in the European Broadcasting Area; its headquarters is in Geneva *.
* European Broadcasting Union
Case Postale 67
CH-1218 GRAND SACONNEX (Geneva)
Switzerland
Tel: +41 22 717 21 11
Fax: +41 22 717 24 81
This ETS describes framing structure, channel coding and modulation for digital television emission by
satellite, it has been prepared by the Project Team PT-55V. The work of the Project Team was based on
the studies carried out by European DVB Project under the auspices of the Ad hoc Group V4/MOD-B.
This joint group of industry, operators and broadcasters provided the necessary information on all relevant
matters to the Project Team, see DTVB 1110/GT V4/MOD 252/ DTVC 18 (bibliography).
This ETS is part of the complete "Multivision system" (the name "Multivision system" is currently under
review) which covers the baseband image coding, baseband sound coding, baseband data service
coding, multiplexing, channel coding and modulation for satellite services, channel coding and modulation
for cable distribution and common scrambling system.
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ETS 300 421: December 1994
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ETS 300 421: December 1994
1 Scope
This European Telecommunication Standard (ETS) describes the modulation and channel coding system
(denoted the "System" for the purposes of this ETS) for satellite digital multi-programme Television
(TV)/High Definition Television (HDTV) services to be used for primary and secondary distribution in Fixed
Satellite Service (FSS) and Broadcast Satellite Service (BSS) bands. The System is intended to provide
Direct-To-Home (DTH) services for consumer Integrated Receiver Decoder (IRD), as well as collective
antenna systems (Satellite Master Antenna Television (SMATV)) and cable television head-end stations,
with a likelihood of remodulation, see ETS 300 429 (bibliography).
The System uses Quaternary Phase Shift Keying (QPSK) modulation and concatenated error protection
strategy based on a convolutional code and a shortened Reed-Solomon (RS) code.
The System is suitable for use on different satellite transponder bandwidths.
Compatibility with Moving Pictures Experts Group-2 (MPEG-2) coded TV services (see ISO/IEC DIS
13818-1 [1]), with a transmission structure synchronous with the packet multiplex, is provided. Exploitation
of the multiplex flexibility allows the use of the transmission capacity for a variety of TV service
configurations, including sound and data services. All service components are Time Division Multiplexed
(TDM) on a single digital carrier.
This ETS:
- gives a general description of the System for satellite digital TV transmission;
- specifies the digitally modulated signal in order to allow compatibility between pieces of equipment
developed by different manufacturers. This is achieved by describing in detail the signal processing
principles at the modulator side, while the processing at the receive side is left open to different
implementation solutions. However, it is necessary in this ETS to refer to certain aspects of
reception;
- identifies the global performance requirements and features of the System, in order to meet the
service quality targets.
2 Normative references
This ETS incorporates by dated and undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications
apply to this ETS only when incorporated in it by amendment or revision. For undated references the latest
edition of the publication referred to applies.
[1] ISO/IEC DIS 13818-1 (June 1994): "Coding of moving pictures and associated
audio".
[2] Forney, G.D. IEEE Trans. Comm. Tech., COM-19, pp. 772-781, (October 1971):
"Burst-correcting codes for the classic bursty channel".
[3] Intelsat Earth Station Standards (IESS) No. 308, revision 6 (26 October 1990):
"Performance characteristics for Immediate Data Rate (IDR) digital carriers".
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ETS 300 421: December 1994
3 Symbols and abbreviations
3.1 Symbols
For the purposes of this ETS, the following symbols apply:
α Roll-off factor
C/N Signal-to-noise ratio
d Convolutional code free distance
free
E /N Ratio between the energy per useful bit and twice the noise power spectral
b 0
density
f Nyquist frequency
N
G ,G Convolutional code generators
1 2
g(x) RS code generator polynomial
I Interleaving depth [bytes]
I, Q In-phase, Quadrature phase components of the modulated signal
j Branch index of the interleaver
K Convolutional code constraint length
M Convolutional interleaver branch depth for j = 1, M = N/I
N Error protected frame length (bytes)
p(x) RS field generator polynomial
r In-band ripple (dB)
m
R Symbol rate corresponding to the bilateral Nyquist bandwidth of the modulated
s
signal
R Useful bit rate after MPEG-2 [1] transport multiplexer
u
R ' Bit rate after RS outer coder
u
T Number of bytes which can be corrected in RS error protected packet
T Symbol period
s
X,Y Di-bit stream after rate 1/2 convolutional coding
3.2 Abbreviations
For the purposes of this ETS, the following abbreviations apply:
AWGN Additive White Gaussian Noise
BB Baseband
BER Bit Error Ratio
BSS Broadcast Satellite Service
BW Bandwidth
CCITT International Telegraph and Telephone Consultative Committee
DTH Direct To Home
EBU European Broadcasting Union
ETS European Telecommunication Standard
FDM Frequency Division Multiplex
FEC Forward Error Correction
FIFO First-In, First-Out shift register
FIR Finite Impulse Response
FSS Fixed Satellite Service
HEX Hexadecimal notation
HDTV High Definition Television
IF Intermediate Frequency
IMUX Input Multiplexer - Filter
IRD Integrated Receiver Decoder
ITU International Telecommunications Union
MPEG Moving Pictures Experts Group
MSB Most Significant Bit
MUX Multiplex
OBO Output Back Off
OCT Octal notation
OMUX Output Multiplexer - Filter
P Puncturing
PDH Plesiochronous Digital Hierarchy
PSK Phase Shift Keying
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ETS 300 421: December 1994
PRBS Pseudo Random Binary Sequence
QEF Quasi-Error-Free
QPSK Quaternary PSK
R Randomized sequence
RF Radio Frequency
RS Reed-Solomon
SMATV Satellite Master Antenna Television
TBD To Be Defined
TDM Time Division Multiplex
TV Television
TWTA Travelling Wave Tube Amplifier
4 Transmission system
4.1 System definition
The System is defined as the functional block of equipment performing the adaptation of the baseband TV
signals, from the output of the MPEG-2 transport multiplexer (see ISO/IEC DIS 13818-1 [1]), to the
satellite channel characteristics. The following processes shall be applied to the data stream (see figure
1):
- transport multiplex adaptation and randomization for energy dispersal;
- outer coding (i.e. Reed-Solomon);
- convolutional interleaving;
- inner coding (i.e. punctured convolutional code);
- baseband shaping for modulation;
- modulation.
The System functional description is given in annex B.
DTH services via satellite are particularly affected by power limitations, therefore, ruggedness against
noise and interference, shall be the main design objective, rather than spectrum efficiency. To achieve a
very high power efficiency without excessively penalizing the spectrum efficiency, the System shall use
QPSK modulation and the concatenation of convolutional and RS codes. The convolutional code is able to
be configured flexibly, allowing the optimization of the system performance for a given satellite
transponder bandwidth (see annex C).
Although the System is optimized for single carrier per transponder Time Division Multiplex (TDM), it is
able to be used for multi-carrier Frequency Division Multiplex (FDM) type applications.
Figure 1: Functional block diagram of the System
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ETS 300 421: December 1994
The System is directly compatible with MPEG-2 coded TV signals (see ISO/IEC DIS 13818-1 [1]). The
modem transmission frame is synchronous with the MPEG-2 multiplex transport packets.
If the received signal is above C/N and C/I threshold, the Forward Error Correction (FEC) technique
adopted in the System is designed to provide a "Quasi Error Free" (QEF) quality target. The QEF means
less than one uncorrected error-event per transmission hour, corresponding to Bit Error Ratio
-10 -11
(BER) = 10 to 10 at the input of the MPEG-2 demultiplexer.
4.2 Adaptation to satellite transponder characteristics
Transmissions of digital multi-programme TV services will use satellites in both the FSS and the BSS
bands. The choice of transponder bandwidth is a function of the satellite used and the data rates required
by the service.
The symbol rate shall be matched to given transponder characteristics. Examples based on computer
simulations for a hypothetical satellite chain, not including interference effects, are given in annex C.
4.3 Interfacing
The System, as defined in this ETS, shall be delimited by the following interfaces given in table 1:
Table 1: System interfaces
Location Interface Interface type Connection
Transmit station Input MPEG-2 [1] transport from MPEG-2
multiplex multiplexer
Output 70/140 MHz IF to RF devices
Receive installation Output MPEG-2 transport to MPEG-2
multiplex demultiplexer
Input TBD from RF devices
(indoor unit)
4.4 Channel coding
4.4.1 Transport multiplex adaptation and randomization for energy dispersal
The System input stream shall be organized in fixed length packets (see figure 3), following the MPEG-2
transport multiplexer (see ISO/IEC DIS 13818-1 [1]). The total packet length of the MPEG-2 transport
Multiplex (MUX) packet is 188 bytes. This includes 1 sync-word byte (i.e. 47 ). The processing order at
HEX
the transmitting side shall always start from the MSB (i.e. "0") of the sync word-byte (i.e. 01000111).
In order to comply with ITU Radio Regulations and to ensure adequate binary transitions, the data of the
input MPEG-2 multiplex shall be randomized in accordance with the configuration depicted in figure 2.
The polynomial for the Pseudo Random Binary Sequence (PRBS) generator shall be:
14 15
1 + X + X
Loading of the sequence "100101010000000" into the PRBS registers, as indicated in figure 2, shall be
initiated at the start of every eight transport packets. To provide an initialization signal for the descrambler,
the MPEG-2 sync byte of the first transport packet in a group of eight packets is bit-wise inverted from
47 to B8 . This process is referred to as the "Transport Multiplex Adaptation".
HEX HEX
The first bit at the output of the PRBS generator shall be applied to the first bit (i.e. MSB) of the first byte
following the inverted MPEG-2 sync byte (i.e. B8 ). To aid other synchronization functions, during the
HEX
MPEG-2 sync bytes of the subsequent 7 transport packets, the PRBS generation shall continue, but its
output shall be disabled, leaving these bytes unrandomized. Thus, the period of the PRBS sequence shall
be 1 503 bytes.
The randomization process shall be active also when the modulator input bit-stream is non-existent, or
when it is non-compliant with the MPEG-2 transport stream format (i.e. 1 sync byte + 187 packet bytes).
This is to avoid the emission of an unmodulated carrier from the modulator.
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ETS 300 421: December 1994
Initialization sequence
1100 01 01 0000000
1 2 3 4 5 6 7 8 9 101112 13 14 15
0 0 0 0 0 0 1 1 .
EX-OR
AND
EX-OR
R andom ized/de-random ized
data output
Enable Clear/randomized
data input
Data input (MSB first): 1 0 1 1 1 0 0 0 x x x x x x x x .
PRBS sequence : 0 0 0 0
...