ETSI ETS 300 234 ed.1 (1995-07)
Transmission and Multiplexing (TM); High capacity digital radio-relay systems carrying 1 x STM-1 signals and operating in frequency bands with about 30 MHz channel spacing and alternated arrangements
Transmission and Multiplexing (TM); High capacity digital radio-relay systems carrying 1 x STM-1 signals and operating in frequency bands with about 30 MHz channel spacing and alternated arrangements
DE/TM-04005
Prenos in multipleksiranje (TM) – Visoko zmogljivi digitalni radiorelejni sistemi, ki izmenično prenašajo signale 1 x STM-1 in delujejo v frekvenčnih pasovih z medkanalskim razmikom približno 30 MHz
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST ETS 300 234 E1:2003
01-december-2003
3UHQRVLQPXOWLSOHNVLUDQMH70±9LVRNR]PRJOMLYLGLJLWDOQLUDGLRUHOHMQLVLVWHPLNL
L]PHQLþQRSUHQDãDMRVLJQDOH[670LQGHOXMHMRYIUHNYHQþQLKSDVRYLK]
PHGNDQDOVNLPUD]PLNRPSULEOLåQR0+]
Transmission and Multiplexing (TM); High capacity digital radio-relay systems carrying 1
x STM-1 signals and operating in frequency bands with about 30 MHz channel spacing
and alternated arrangements
Ta slovenski standard je istoveten z: ETS 300 234 Edition 1
ICS:
33.040.20 Prenosni sistem Transmission systems
33.060.30 Radiorelejni in fiksni satelitski Radio relay and fixed satellite
komunikacijski sistemi communications systems
SIST ETS 300 234 E1:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN ETS 300 234
TELECOMMUNICATION July 1995
STANDARD
Source: ETSI TC-TM Reference: DE/TM-04005
ICS: 33.080
Digital, radio
Key words:
Transmission and Multiplexing (TM);
High capacity digital radio-relay systems carrying 1 x STM-1
signals and operating in frequency bands with about 30 MHz
channel spacing and alternated arrangements
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 1995. All rights reserved.
New presentation - see History box
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ETS 300 234: July 1995
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 300 234: July 1995
Contents
Foreword .5
1 Scope .7
2 Normative references.8
3 Abbreviations and symbols .9
3.1 Abbreviations .9
3.2 Symbols .9
4 Network and system considerations .9
5 General characteristics .10
5.1 Frequency bands and channel arrangements .10
5.2 Modes of operation .10
5.3 Types of installation .10
5.3.1 Environmental conditions .10
5.3.1.1 Equipment within weatherprotected locations .11
5.3.1.2 Equipment for non-weatherprotected locations.11
5.3.2 Electromagnetic compatibility conditions.11
5.3.3 Mechanical dimensions.12
5.3.4 Power supply.12
5.3.5 Safety considerations .12
5.4 Telecommunications Management Network (TMN) interface .12
5.5 System block diagram .13
5.6 Intermediate Frequency (IF) .13
5.7 Local oscillator arrangements.13
6 Transmitter characteristics.14
6.1 Output power .14
6.2 Automatic Transmit Power Control (ATPC).14
6.3 RF spectrum masks.14
6.4 Spectral lines at the symbol rate.19
6.5 Spurious emissions.19
6.5.1 Spurious emissions - external .19
6.5.2 Spurious emissions - internal .19
6.6 Radio frequency tolerance.20
6.7 Return loss.20
7 Receiver characteristics .20
7.1 Receiver image rejection .20
7.2 Spurious emissions.20
7.2.1 Spurious emissions - external .20
7.2.2 Spurious emissions - internal .20
7.3 Input level range .21
7.4 Overall receiver selectivity for the L6 GHz innermost channels.21
7.5 Return loss.23
8 System characteristics without diversity.23
8.1 Equipment background BER .23
8.2 BER as a function of receiver input level .23
8.3 Interference sensitivity .23
8.3.1 Co-channel interference sensitivity .23
8.3.2 Adjacent channel interference sensitivity .25
8.3.3 CW Spurious Interference.25
8.4 Distortion sensitivity .25
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ETS 300 234: July 1995
9 System characteristics with diversity . 25
9.1 Differential delay compensation . 25
9.2 BER performance. 25
Annex A (informative): Branching/feeder/antenna requirements . 26
A.1 Cross-Polar Discrimination (XPD) . 26
A.1.1 Intermodulation products. 26
A.1.2 Interport isolation. 26
A.1.3 Return loss . 26
A.2 ATPC . 26
Annex B (informative): Bibliography . 27
History. 28
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ETS 300 234: July 1995
Foreword
This European Telecommunication Standard (ETS) has been produced by the Transmission and
Multiplexing (TM) Technical Committee of the European Telecommunications Standards Institute (ETSI).
This ETS contains the minimum technical requirements to ensure compatibility of products and
conformance with radio regulations across ETSI member states. Radio terminals from different
manufacturers are not required to interwork at radio frequency (i.e. no common air interface). However,
terminals may be combined with other manufacturers equipment on an Radio Frequency (RF) branching
network for operation on different polarizations.
This ETS defines the requirements of radio terminal and radio relay equipment and associated interfaces.
The requirements for multiplex, network management and antenna/feeder equipment may be addressed
elsewhere.
Proposed transposition dates
Date of latest announcement of this ETS (doa): 31 October 1995
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 30 April 1996
Date of withdrawal of any conflicting National Standard (dow): 30 April 1996
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Blank page
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1 Scope
This European Telecommunication Standard (ETS) specifies parameters for digital radio-relay systems
with a channel capacity of 1 x Synchronous Transport Module-level 1 (1 x STM-1) designed to operate in
defined bands up to 15 GHz utilising approximately 30 MHz between adjacent cross-polar channels.
The parameters specified fall into two categories:
a) those required to provide compatibility between channels from different sources of equipment on
the same route, connected either to separate antennas, or to separate polarizations of the same
antenna. This category also includes parameters providing compatibility with the existing radio-relay
network;
b) parameters defining the transmission quality of the proposed systems.
The task of defining compatibility requirements with analogue and digital systems on the same hop and at
nodes is made complex by the fact that analogue systems and some digital systems are not standardized.
Compatibility requirements are, therefore, limited to allowing the operation of digital and analogue
channels on separate ports of the same antenna.
The standardization includes the following specifications:
- transmitter and receiver characteristics;
- baseband and Radio Frequency (RF) interface characteristics;
- diversity system characteristics.
Two possible baseband interfaces have to be considered:
- one for STM-1 signals (electrical and/or optical) in accordance with ITU-R Recommendation 750;
and
- one for 140 Mbit/s plesiochronous signals (only electrical), according to ITU-T recommendation
G.703.
The 140 Mbit/s signals should be carried "open-port", i.e. in a transparent manner independent of their
content. They should be mapped into a 155 Mbit/s STM-1 signal as described in ITU-T Recommendations
G.708 and G.709.
As regards the STM-1 signal the Section Overhead (SOH) processing is covered in a separate ETSI STC
TM 4 document (a report on Synchronous Digital Hierarchy (SDH) aspects) and in ITU-R
Recommendation 750 [7].
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2 Normative references
This ETS incorporates by dated or 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] ITU-R Recommendation 382: "Radio-frequency channel arrangements for
medium and high capacity analogue radio-relay systems operating in the 2 and
4 GHz bands, or for medium and high capacity digital radio-relay systems
operating in the 4 GHz band".
[2] ITU-R Recommendation 385: "Radio-frequency channel arrangements for
radio-relay systems operating in the 7 GHz band".
[3] ITU-R Recommendation 383: "Radio-frequency channel arrangements for
radio-relay systems operating in the Lower 6 GHz band".
[4] ITU-R Recommendation 386, Annex I: "Description of the radio-frequency
channel arrangement referred to in recommends 7".
[5] ITU-R Recommendation 497: "Radio-frequency channel arrangements for low
and medium capacity analogue or medium and high capacity digital radio-relay
systems operating in the 13 GHz band".
[6] ITU-R Recommendation 636: "Radio-frequency channel arrangements for
radio-relay systems operating in the 15 GHz band".
[7] ITU-R Recommendation 750: "Architectures and functional aspects of
radio-relay systems for SDH-based networks".
[8] ITU-R Recommendation 751: "Transmission characteristics and performance
requirements of radio-relay systems for SDH-based networks".
[9] ETS 300 019: "Equipment Engineering (EE); Environmental conditions and
environmental tests for telecommunications equipment".
[10] ETS 300 132: "Equipment Engineering (EE); Power supply interface at the input
to telecommunications equipment".
[11] CEPT Recommendation T/L 04-04: "Harmonization of 140 Mbit/s digital radio
relay systems for operation below 10 GHz utilising 64 QAM at about 30 MHz
spacing".
[12] ITU-T Recommendation G.708 (1990): "Network Node Interface for the
Synchronous Digital Hierarchy".
[13] ITU-T Recommendation G.709 (1990): "Synchronous Multiplexing Structure".
[14] ITU-T Recommendation G.773: "Protocol Suites for Q-Interfaces for
Management of Transmission Systems".
[15] ITU-T Recommendation G.784: "Synchronous Digital Hierarchy Management".
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3 Abbreviations and symbols
3.1 Abbreviations
For the purpose of this ETS the following abbreviations apply.
ATPC Automatic Transmit Power Control
BER Bit Error Ratio
DRRS Digital Radio-Relay System
IF Intermediate Frequency
L6 Lower 6 (GHz band)
PRBS Pseudo-Random Binary Sequence
QAM Quadrature Amplitude Modulation
RF Radio Frequency
Rx Receive (Receiver)
SDH Synchronous Digital Hierarchy
SOH Section Overhead
STM-1 Synchronous Transport Module-level 1
TMN Telecommunications Management Network
Tx Transmit (Transmitter)
VSWR Voltage Standing Wave Ratio
XPD Cross-Polar Discrimination
3.2 Symbols
For the purpose of this ETS the following symbols apply:
dB decibel
dBm decibel relative to 1 mW
GHz GigaHertz
km kilometre
m/s metres per second
Mbit/s Megabit per second
MHz MegaHertz
ns nanosecond
ppm parts per million
W/m² Watts per square metre
4 Network and system considerations
The area of application of these digital radio-relay systems is foreseen to be in regional and trunk
networks. Consideration shall be given to the special requirement in the case of a regional network, e.g.
simpler towers with less space for antenna, different network structures with high density nodes.
Application may also be envisaged for local links and unidirectional connections.
Systems considered in this ETS should be able to respect ITU-R high grade performance objectives.
The systems considered should operate in these networks having regard for existing hop lengths, which
are considered to be normally up to about 30 km - 40 km for regional and about 60 km for trunk networks,
respectively. Hop lengths greater than this latter length, up to about 100 km, are used in special
applications.
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5 General characteristics
5.1 Frequency bands and channel arrangements
The systems shall be required to operate in the following frequency bands, to the specified ITU-R
Recommendation on the quoted channel spacings.
4 GHz
ITU-R Recommendation 382 [1] with 29 MHz channel spacing. The centre gap between transmitters and
receivers in ITU-R Recommendation 382 [1] is 68 MHz.
Lower 6 GHz
ITU-R Recommendation 383 [3] with 29,65 MHz spacing and a centre gap of 44,49 MHz. The alternative
plan in which channels 8 and 1' operate on opposite polarizations should be utilised.
7 GHz
A number of frequency channelling plans are in use at 7 GHz, including that given in ITU-R
Recommendation 385 [2] Annex III. These plans all make use of 28 MHz channel spacing with centre
gaps of 56 MHz or 84 MHz.
8 GHz
ITU-R Recommendation 386 [4], Annex 1, with 29,650 MHz spacing and a centre gap of 103,770 MHz.
13 GHz
ITU-R Recommendation 497 [5] with 28 MHz spacing and a centre gap of 70 MHz.
15 GHz
ITU-R Recommendation 636 [6] with 28 MHz spacing. The centre gap shall be equal to N x 28 MHz (N
integer) and greater than 84 MHz.
5.2 Modes of operation
The mode of operation shall make use of alternate polarizations for adjacent channels in all frequency
bands up to 15 GHz (covered by this ETS).
It should be noted that systems designed for co-frequency cross-polar operation with a 30 MHz channel
spacing are also expected to comply at least with the specifications contained in this ETS.
However, more stringent specifications for spectrum masks and interference sensitivity would certainly be
required for co-frequency cross-polar operation.
5.3 Types of installation
For frequency bands below 10 GHz mainly indoor installations are foreseen.
For radio-relay systems operating in the 13 GHz and 15 GHz bands both indoor and partially outdoor
installations are foreseen.
5.3.1 Environmental conditions
The equipment shall be required to meet either the environmental conditions set out in
ETS 300 019-1-3 [9] and ETS 300 019-1-4 [9], which define weatherprotected and non-weatherprotected
locations, classes and test severities, or one of the conditions listed in subclause 5.3.1.2.
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5.3.1.1 Equipment within weatherprotected locations
The most important climatic parameters for the five classes defined are given in table 1.
Table 1
Climatic class 3.1 3.2 3.3 3.4 3.5
High air temperature (ºC) +40 +45 +55 +70 +40
Low air temperature (ºC) +5 -5 -25 -40 -40
85 95 100 100 100
High relative humidity (%)
Low relative humidity (%) 5 5 10 10 10
55 55 5
Air movement (m/s)
Solar radiation (W/m²) 700 700 1 120 1 120 -
For equipment designed for stationary use in weatherprotected locations (indoor installation), only classes
3.1 or 3.2 shall apply (see ETS 300 019-1-3 [9]).
5.3.1.2 Equipment for non-weatherprotected locations
This type of equipment is generally described as "outdoor" equipment. Class 4.1 or extended class 4.1E
parameters should be applied. Class 4.1 applies to many ETSI countries and class 4.1E applies to them
all. The most important parameters values are given in table 2.
Table 2
Climatic class 4.1 4.1E
+40 +45
High air temperature (ºC)
Low air temperature (ºC) -33 -45
100 100
High relative humidity (%)
Low relative humidity (%) 15 8
Air movement (m/s) +50 +50
1 120 1 120
Solar radiation (W/m²)
It should be noted that radio cabinets supplied with a system will give their own "weather protection"
including full protection against precipitation and wind. Climatic classes 3.3, 3.4 and 3.5 (subclause
5.3.1.1) may, therefore, also be applicable to equipment in outdoor locations.
The operation of the outdoor equipment in accordance with Class 4.1E shall not be mandatory for all ETSI
members.
Some ETSI members may also decide to apply one of the non-standard specifications given in table 3.
Table 3
High air temperature (ºC) +40 +50
Low air temperature (ºC) -20 -30
90 90
High relative humidity (%)
Low relative humidity (%) 55
Air movement (m/s) +50 +50
1 120 1 120
Solar radiation (W/m²)
5.3.2 Electromagnetic compatibility conditions
Equipment shall operate under the conditions specified in relevant standards produced by the appropriate
European standard organizations (under study in ETSI STC RES 9).
For enclosure emissions and immunity to RF electromagnetic fields, the range of frequencies is extended
to cover frequencies up to 2 GHz.
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5.3.3 Mechanical dimensions
The mechanical dimensions for indoor installations should be in agreement with ETS 300 119.
The following parameters should be taken into account in the design of equipment incorporating an
external unit:
a) maximum weight of the external unit;
b) size of external unit for wind loading considerations;
c) maximum weight of replaceable units;
d) ease of access to replaceable units.
5.3.4 Power supply
The equipment shall operate from any of the supply voltages within the ranges specified in
ETS 300 132 [10]. According to ETS 300 132 [10], the normal values and tolerances, as given in table 4,
are specified.
Table 4
48 V DC: - 40,5 - 57,0 V DC
- 50 - 72 V DC
60 V DC
230 V AC 207 253 V AC/50 Hz ± 2 Hz
For DC systems, the positive pole of the battery shall be earthed.
NOTE: Some countries may require to use a primary supply of 24 V DC or 110 V AC, which is
not covered by ETS 300 132 [10].
5.3.5 Safety considerations
Maximum radiated power density under normal operating conditions shall be in accordance with current
World Health Organization figures.
5.4 Telecommunications Management Network (TMN) interface
Where provided, a TMN interface shall follow relevant ITU-T and ITU-R Recommendations and ETSs.
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5.5 System block diagram
The system block diagram including reference points is shown in figure 1. These points are reference
points only and not necessarily measurement points.
The receiver diversity path shown in the block diagram refers only to combining techniques.
Z' A' B' C' D'
Branching
Transm itter
RF Tx filter Feeder
netw ork
(note 3)
(note 1)
D C B A EZ
Branching
Feeder
RF Rx filter Dem odulator
network Receiver
(note 1)
(note 3)
Main receiver path
(note 2) (note 2)
Branching
Dd Cd Bd Ad Ed
netw ork RF Rx filter
Receiver Dem odulator
Feeder
(note 1)
Diversity receiver path
NOTE 1: No filtering included.
NOTE 2: Connection at RF, IF or baseband.
NOTE 3: A 155 Mbit/s or 140 Mbit/s interface is used at points Z and Z'.
Figure 1: Block diagram
5.6 Intermediate Frequency (IF)
If any, the IF should preferably be 70 MHz.
5.7 Local oscillator arrangements
When an IF is used, the local oscillator frequencies for both, transmitters and receivers, shall be in the
same half-band as their associated transmitter or receiver carrier frequencies.
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6 Transmitter characteristics
6.1 Output power
Referred to point B' the value of the output power shall be less or equal to +38 dBm and greater or equal
to +20 dBm, all tolerances included.
Depending on environmental conditions (see subclause 5.3.1) the nominal output power tolerance should
be within:
+1 dB/-1 dB for the classes 3.1 and 3.2;
+2 dB/-1 dB for all other classes.
NOTE: For the purpose of system engineering four classes of nominal output power are
defined (see intervals in table 5).
Equipments of different output power classes are not considered to require individual type approval,
however this is subject to individual national agreements.
Table 5
Class A < + 26 dBm
< + 31 dBm
Class B ≥ + 26 dBm
Class C < + 34 dBm
≥ + 29 dBm
Class D ≥ + 34 dBm
In the case of a 140 Mbit/s transport signal, the measurement shall be carried out with the carrier
23
modulated by a pseudo-random bit sequence 2 -1.
In the case of a STM-1 signal the measurement shall be carried out using an STM-1 test signal to be
defined.
6.2 Automatic Transmit Power Control (ATPC)
ATPC is an optional feature, information on ATPC is given in an informative annex (see annex A, clause
A.2).
6.3 RF spectrum masks
The three main factors considered in recommending a mask are as follows:
a) control of interference into analogue channels operating on the adjacent channel allocation on the
orthogonal polarization;
b) control of interference into digital channels from a different manufacturer's equipment operating on
the adjacent channel allocation on the orthogonal polarization;
c) different transmitter characteristics.
The spectrum mask given in figure 2 for all frequency bands considered is based on a level of
compatibility required, which is identical to that considered in CEPT Recommendation T/L 04-04 [11]. It
allows compatibility between systems defined in this ETS and those specified in the CEPT
Recommendation.
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If, depending on application, administrations or operating companies do not require compatibility with
systems specified in CEPT Recommendation T/L 04-04 [11], a slightly relaxed spectrum mask as given in
figure 2 curve c), may be applied. However, all other specifications in this ETS shall be met.
The spectrum mask marked (a) in figure 2 shall be verified directly by measurement (referenced to point
B'). Since it is not possible to measure attenuation values up to 105 dB directly, values of the relative
power spectral density below -65 dB in figure 2 (curve (b)) and figures 3 and 4 should be verified by
adding a measured filter characteristic to the spectrum at A'.
Masks shall be measured with a modulating baseband signal, given by a Pseudo-Random Binary
23
Sequence (PRBS) 2 -1 in the case of a 140 Mbit/s signal, or an STM-1 test signal to be defined.
The spectrum masks are referenced to the level at the centre of the spectrum excluding any residual
carrier and to the actual carrier frequency; they shall be verified for the actual output power. The frequency
tolerance is not included in the masks.
The spectrum analyser settings for measuring the RF spectrum masks are given below in table 6.
Table 6
Parameter Setting
IF bandwidth 100 kHz
Total sweep width 200 MHz
Total scan time 20 s
Video filter bandwidth 0,3 kHz
For the Lower 6 (L6) GHz band, where the centre gap (44,49 MHz) is particularly small, a mask is
specified for the innermost edges of the centre gap channels 8 and 1' (referenced to point B'), the mask is
given in figure 3.
A mask for the innermost channels in the 7 GHz band (centre gap 56 MHz) is given in figure 4.
The mask labelled (b) in figure 2 fixes a lower limit of - 105 dB in order to control local interference
between transmitters and receivers as for the innermost channels.
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NOTE: Frequency tolerance not included in the mask.
Figure 2: Limits of spectral power density for normal channels (reference point B')
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10
15 MHz/+1dB
0
relative
power
13 MHz/+1 dB
- 10
spectral
(c)
density
- 20
(dB)
21 MHz/-35 dB
- 30
- 40
20 MHz/-35 dB
- 50
- 60
(a)
31,5 MHz/-65 dB
- 70
- 80
- 90
(b)
- 100
60 MHz/-105 dB
- 110
0 10
20 30 40 50 60 70
Frequency offset from the actual centre frequency (MHz)
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NOTE: Frequency tolerance not included in the mask.
Figure 3: Limits of spectral power density for the inner edges of innermost channels, L6 GHz band
(reference point B')
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10
15 MHz/+1 dB
0
relative
13 MHz/+1 dB
- 10
power
spectral
- 20
den
...
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