UK Voluntary National Specification 2111
Performance parameters for Scanning Telemetry and Telecontrol
Systems operating in the frequency band 457.5 MHz to 464.0 MHz
(Version 1.0)
98/34/EC Notification Number: 2000/XXX/UK
Contents
1.
FOREWORD
3
2.
ABBREVIATIONS AND SYMBOLS.
4
2.1
2.2
3.
ABBREVIATIONS
SYMBOLS
4
4
EQUIPMENT PERFORMANCE PARAMETERS AND LIMITS
3.1
3.2
4.
MAXIMUM PERMISSIBLE FREQUENCY DEVIATION.
SPECIFICATIONS FOR ADJACENT CHANNEL POWER MEASUREMENT ARRANGEMENTS
ANTENNA REQUIREMENTS
4.1
4.2
4.3
5
8
8
9
POLARISATION
SPECIFICATION LIMITS
EQUIVALENT ISOTROPICALLY RADIATED POWER (EIRP)
9
9
9
A.1
INTRODUCTION
15
A.2
INPUT AND OUTPUT PORTS
15
A.3
PROCEDURES FOR TESTS AT EXTREME TEMPERATURES
15
A 3.1
A 3.2
EQUIPMENT DESIGNED FOR CONTINUOUS OPERATION
EQUIPMENT DESIGNED FOR INTERMITTENT OPERATION
15
15
A.4
ARRANGEMENTS FOR TEST SIGNALS AT THE INPUT TO THE RECEIVER
15
A.5
RECEIVER MUTE OR SQUELCH FACILITY
16
A.6
RECEIVER RATED AUDIO OUTPUT POWER
16
A.7
NORMAL TEST MODULATION
16
A.8
TRANSMITTER ARTIFICIAL LOAD
16
A.9
MEASURING FREQUENCY ERROR
16
A.10
CARRIER POWER MEASUREMENT
16
A.11
MAXIMUM PERMISSIBLE FREQUENCY DEVIATION MEASUREMENT
16
A.12
RESPONSE OF THE TRANSMITTER AT MODULATION FREQUENCIES ABOVE 3 KHZ
16
A.13
ADJACENT CHANNEL POWER
16
A.14
TRANSMITTER SPURIOUS EMISSION MEASUREMENT
17
A.15
REFERENCE SENSITIVITY MEASUREMENT
17
Page 1 of 18
VNS 2111 Issue 1:
A.16
ADJACENT CHANNEL SELECTIVITY
17
A.17
SPURIOUS RESPONSE REJECTION
17
A.18
RECEIVER SPURIOUS EMISSIONS MEASUREMENT
17
A.19
ANTENNA TESTING
17
A 19.1
POLARISATION
17
Page 2 of 18
VNS 2111 Issue 1:
1.
1.1
1.2
1.3
these exist, and in other cases are
calculated for this specific frequency
band. This specification also includes a
number of “non-essential parameters”, as
do the ETSI standards, which are
included for reasons of spectrum
efficiency and are used in the national
frequency assignment process.
Foreword
The Radio and Telecommunications
Terminal Equipment (R&TTE) Directive
came in to force on the 8th April 2000.
This directive removes the need for
national type approval regimes allowing
manufacturers
to
self
declare
conformance to the R&TTE Directive, via
a number of possible routes detailed in
the directive.
Once a declaration of
conformance has been made, and
notification procedures with the relevant
spectrum management authorities have
been completed, where applicable, the
manufacturer is free to sell the equipment
in all European Union (EU) member
states.
In the UK the spectrum
management
authority
is
the
Radiocommunications Agency (RA), refer
to information sheet RA368 for details of
the notification procedure.
In order to declare conformance with the
R&TTE Directive the manufacturers must
satisfy the “essential requirements” laid
out in the R&TTE Directive. It is the
responsibility
of
the
European
Telecommunication Standards Institute
(ETSI) to develop harmonised standards
under mandate from the European
Commission. Compliance with these
harmonised
standards
gives
a
presumption of conformity with the
“essential requirements” of the Directive.
In the absence of a relevant ETSI
Harmonised Standard for Scanning
Telemetry applications this VNS Identifies
“essential parameters”, and the numeric
values associated with these “essential
parameters” with reference to ETSI
Candidate Harmonised Standards EN 300
113-2 and EN 300 086-2. The noted
Candidate Harmonised standards cover
similar systems but can not be used
directly for this application hence the need
for this VNS. Throughout table 3.1 this
VNS
identifies
all
“essential
parameters” under Article 3.2 of
Directive 99/5/EC as entries in bold
italics.
1.4
This document gives no presumption of
conformity to the R&TTE Directive.
Manufacturers should consult the R&TTE
Directive specifically annexes II, III, IV and
V that detail the various routes to
conformance with the Directive.
1.5
The details contained in this document will
be used in the national frequency
assignment process for this frequency
band. Additional information on licensing
of systems and antenna requirements can
be found in the UK Radio Interface
Requirement 2037 (I/R 2037) document.
The I/R 2037 also contains reference to
the
relevant
national
frequency
assignment criteria document.
1.6
This VNS should be used in conjunction
with the I/R 2037, R&TTE Directive, the
relevant national frequency assignment
criteria and the documents referenced
within these publications that relate to this
frequency band.
1.7
It is acknowledged that the use of any
equivalent standards, produced by any
relevant body of any European Economic
Area (EEA) state, will be accepted as
fulfilling the purpose of this VNS.
1.8
Further information on this VNS can be
obtained from the technical enquiry
contact, details are given on the back of
this document along with contact details
for more general enquiries.
There is currently no ETSI standard for
the frequency band covered by this
Voluntary National Specification (VNS).
This VNS takes the parameters identified
in the ETSI Candidate Harmonised
Standard and supplies relevant numerical
limits, which are taken directly from
relevant European documents where
Page 3 of 18
VNS 2111 Issue 1:
2.
Abbreviations and Symbols.
2.2
2.1
Abbreviations
For the purpose of this UK VNS, the following
symbols apply.
For the purpose of this VNS, the following
abbreviations apply:
CW
C/I
CEPT
EC
EIRP
EN
ETS
ETSI
IF
I/R
ITU-R
ITU-T
RA
RF
RMS
RSL
R&TTED
RX
TM
TX
VNS
W/U
Continuous Wave
Carrier to Interference
(ratio in dB)
Conférence des
Administrations
Européennes des
Postes et
Télécommunications
European Commission
Equivalent Isotropically
Radiated Power
dB
dBm
GHz
kHz
MHz
ppm
European Normative
European
Telecommunications
Standard
European
Telecommunications
Standards Institute
Intermediate
Frequency
Interface
Requirements
International
Telecommunication
Union Radiocommunication
Sector
International
Telecommunication
Union Telecommunication
Standardisation Sector
Radiocommunications
Agency
Radio Frequency
Root Mean Square
Receive signal level
Radio and
Telecommunications
Terminal Equipment
Directive.
Receiver
Transmission and
Multiplexing
Transmitter
Voluntary National
Specification
Wanted to Unwanted
ratio
Page 4 of 18
Symbols
decibel
decibels relative to 1
milliwatt
Gigahertz
kilohertz
Megahertz
parts per million
VNS 2111 Issue 1:
3.
Equipment Performance Parameters and Limits
Table 3.1: Equipment Performance Parameters and Limits
Parameter Reference
Standards
Equipment Parameters and limits
Additional Information
General Characteristics
Channel Plan
Co-polar
Channel Spacing
Adaptable
cellular channel
plan
Details of the channel plan can be
found in the RA report entitled “The
future of UHF Scanning Telemetry
Frequency Assignment – A report for
DTI, JRC and TAG” published
January 1989.
N/A
Channel Spacing (kHz)
12.5
Normal Test
Conditions
15 to 350C and Relative Humidity of 20 % to 75 %
The normal environmental conditions
are any convenient and naturally
occurring combination of
temperature and humidity within the
stated ranges.
Extreme Test
Conditions
–100C to +55 0C
The limits given here are the extreme
temperature range for equipment
that is designed for indoor use.
Carrier Power
Output Power is subject to manufacturer The transmitter power (conducted) is
declaration, but shall not exceed 10 watts in any the mean power delivered to the
case.
artificial antenna during a radio
frequency cycle, in the absence of
modulation.
Transmitter
carrier Power
Tolerance
+2dB –3dB under all environmental conditions
Transmitter Characteristics
Frequency
Error
N/A
 1.5 kHz
Page 5 of 18
The
frequency
error
of
the
transmitter is the difference between
the measured carrier frequency in
the absence of modulation and the
nominal frequency of the transmitter.
VNS 2111 Issue 1:
Parameter Reference
Standards
Maximum
Permissible
frequency
deviation
N/A
Equipment Parameters and limits
Additional Information
Maximum permissible frequency deviation at any
modulating frequency shall not exceed 2.5 kHz.
For modulating frequencies between 3 kHz and 6 kHz
the frequency deviation shall not exceed the frequency
deviation at 3 kHz.
At 6 kHz the frequency deviation shall be at least 6dB
below that of the frequency deviation for a 1 kHz
modulation frequency.
The frequency deviation is the
maximum difference between the
instantaneous frequency of the
modulated radio frequency signal
and the carrier frequency in the
absence of modulation.
For modulating frequencies from 6 kHz to a frequency
equal to the channel separation the frequency deviation
should not exceed the level given by a linear
representation with a slope of 14 dB/octave with the
frequency deviation diminishing as the modulating
frequency increases to a value equal to channel
separation. These limits are illustrated in figure 3.1.
Adjacent
channel power
N/A
Adjacent channel power shall not exceed a value of
55 dB below the carrier power of the transmitter,
without the need to be below –67 dBW (0.2uW).
Refer to section 3.2 for the power measuring receiver
specification and figure 3.2 for the IF filter selectivity
characteristic.
IF Filter
Specification
N/A
Frequency separation of filter curve from Figure The power measuring receiver
nominal centre frequency of adjacent
consists of a mixer, an IF filter, an
channel (kHz) for channel spacing of 12.5
oscillator, an amplifier, a variable
kHz
attenuator and an RMS value
indicator, it is also possible to use an
D1
D2
D3
D4
3.2
RMS voltmeter calibrated in decibels.
3
4.25
5.5
9.5
The technical characteristics of the
power measuring receiver are given
Attenuation Points Close to the Carrier
in Annex A.
Tolerance Range (kHz)
D1
D2
D3
D4
1.35
 0.10
-1.35
-5.35
The adjacent channel power is that
part of the total output power of a
transmitter, under defined conditions
of modulation, which falls within a
specified passband centred in the
nominal frequency of either to the
adjacent channels
3.2
Attenuation Points Distant from the Carrier
Tolerance Range (kHz)
D1
D2
D3
D4
 2.0
 2.0
 2.0
+2.0
3.2
-6.0
Spurious
Emissions
N/A
Any spurious emissions in the frequency range 100 Spurious emissions are emissions at
kHz to 2 GHz shall not exceed a power level of –56 frequencies which are outside the
dBW
necessary bandwidth and the level of
which may be reduced without
affecting
the
corresponding
transmission
of
information.
Spurious emissions include harmonic
emissions,
parasitic
emissions,
intermodulation
products
and
frequency conversion products but
exclude emissions on frequencies
immediately outside the necessary
bandwidth which result from the
modulation process.
Page 6 of 18
VNS 2111 Issue 1:
Receiver Characteristics
Reference
Sensitivity
N/A
Adjacent
channel
selectivity
N/A
For an input signal level of –124 dBW the minimum The reference sensitivity of the
signal to noise ratio at the audio output, un- receiver is the minimum level of
weighted, shall be 27 dB.
signal at the receiver input, at the
nominal frequency of the receiver
and with normal test modulation, that
will produce an audio frequency
output signal at the specified level.
Channel separation (kHz)
The S/N ratio should not be less than 24 dB under
any conditions
At each emission up to 2 GHz, the power of any
spurious emission shall not exceed –77dBW.
Spurious
Emissions
CW Interference
The adjacent channel selectivity is
the capability of the receiver to
receive a wanted modulated signal at
the nominal frequency without
exceeding a given degradation due
to the presence of an unwanted
modulated signal in the adjacent
channel.
N/A
At any frequency separated from the nominal
frequency of the receiver by more than 12.5 kHz the
signal to noise ratio shall not exceed 27 dB
Page 7 of 18
The spurious response rejection is
the capability of the receiver to
discriminate between the wanted
modulated signal at the nominal
frequency and an unwanted signal at
any other frequency at which a
response is obtained.
VNS 2111 Issue 1:
3.1
Maximum Permissible Frequency Deviation.
The frequency deviation of the equipment shall comply with the profile in Figure 3.1.
MPFD
A
30% MPFD
-14 dB/oct.
-14 dB/oct.
f1
f2
6 kHz
fcs
Audio frequency
Frequency deviation
Figure 3.1: Maximum Permissible Frequency Deviation verses Audio Frequency
3.2
Specifications For Adjacent Channel Power Measurement Arrangements
3.2.1
Power measuring receiver specification
The power measuring receiver consists of a mixer, an IF filter, an oscillator, an amplifier, a variable
attenuator and an RMS value indicator. Instead of the variable attenuator with the RMS value indicator it
is also possible to use an RMS voltmeter calibrated in dB as the RMS value indicator. The technical
characteristics of the power measuring receiver are given below.
3.2.1.1
IF Filter
The IF Filter shall be within the limits of the selectivity characteristic given in figure 3.2. The limits
associated with figure 3.2 are given in table 3.1.
dB
90
D4
D3
D4
D3
26
D2
D2
6
2
D1
-8
-4
D1
0
4
Figure 3.2: IF Filter Selectivity Characteristics
Page 8 of 18
8
kHz
VNS 2111 Issue 1:
4.
Antenna Requirements
4.1
Polarisation
The polarisation of radiation shall be either vertical or horizontal. The polarisation to be used for any
specific radio system will be specified when frequencies for the system are assigned.
Radiation in the main beam having a polarisation orthogonal to that which is intended shall not exceed a
level of –20 dB relative to the radiation of energy having the intended polarisation.
4.2
Specification Limits
The measured antenna performance shall meet the minimum requirements specified in table 4.1 below.
Antenna
Type
Limits
Base Station
Omni-directional
The radiation pattern when measured in azimuth shall not
vary by more than  1.5 dB for horizontally and vertically
polarised antennas.
Base Station
Sector coverage
See Figure 4.1
Outstation
Directional
See Figures 4.2 and 4.3
Table 4.1: Antenna Radiation Pattern Envelope Limits
4.3
Equivalent Isotropically Radiated Power (EIRP)
In the band 457.5 to 464.0 MHz the maximum equivalent isotropically radiated power (EIRP) shall not
exceed 24 dBW.
Page 9 of 18
VNS 2111 Issue 1:
Under Test Range Conditions
14
Gain relative
to an isotropic
antenna (dBi)
12
10
12
7.8
10
8
6
8
4
6
2
4
Co-Polarised Response
0
2
0
-2
-2
-4
-6.2
-4
Cross Polarised Response
-6
-8.2
-6
-8
-10
-8
-10
0
20
40 45
60
80
100
120
140
Angle of azimuth relative to the main beam axis 00 ( degrees)
Figure 4.1: Sector Antenna Radiation Pattern Envelope for Base Stations
Page 10 of 18
160
180
Gain relative
to a half-wave
dipole (dBd)
VNS 2111 Issue 1:
Under Test Range Conditions
14
Gain relative
to an isotropic
antenna (dBi)
12
10
12
8.8
11
10
8
8
6
4
6
1.8
4
2
0
2
Co-Polarised Response
0
-2
-4
-2
-6.2
-4
Cross Polarised Response
-6
-8.2
-6
-8
-10
-8
-10
0
15 20
30
40
60
80
100
120
140
160
Angle of azimuth relative to the main beam axis 00 ( degrees)
Figure 4.2: Antenna Radiation Pattern Envelope for Outstations – Standard Antenna
Page 11 of 18
180
Gain relative
to a half-wave
dipole (dBd)
VNS 2111 Issue 1:
14
Gain relative
to an isotropic
antenna (dBi)
Under Test Range Conditions
13.7
11.5
12
12
10
10
8
8
6
4
6
1.8
4
2
0
2
Co-Polarised Response
0
-2
-4
-2
-6.2
-4
Cross Polarised Response
-6
-8.2
-6
-8
-10
-8
-10
0
12
20
40
60
80
100
120
140
160
Angle of azimuth relative to the main beam axis 00 ( degrees)
0 4.3: Antenna Radiation Pattern Envelope for Outstations – High Performance Antenna
Figure
Page 12 of 18
180
Gain relative
to a half-wave
dipole (dBd)
VNS 2111 Issue 1:
Informative Annex
Page 13 of 18
VNS 2111 Issue 1:
Blank Page
Page 14 of 18
VNS 2111 Issue 1:
Introduction
This section of the document is informative and includes data deemed to be helpful to engineers
conducting tests to confirm system performance.
Input and Output Ports
For the purpose of this VNS the “transmitter input port”, “transmitter output port”, “receiver input port” and
“receiver output port” shall be taken to refer to those points corresponding respectively to the points Z’, C’,
C and Z in Figure A1. Points Z’ and Z are baseband input and output points respectively.
Z'
D
Transmitter
Feeder
A'
C
RF Tx Filter
Branching
Network
B'
B
Branching
Network
RF Rx Filter
C'
A
Feeder
Receiver
D'
Z
Figure A1: System Block Diagram
Procedures for Tests at Extreme Temperatures
Equipment should be left un-powered in a temperature controlled chamber for a period of one hour or for
such a period as may be judged necessary to achieve thermal balance before tests are carried out. The
Humidity content in the test chamber shall be controlled so that excessive condensation does not occur.
A 1.1
Equipment designed for continuous operation
For tests at the upper temperature limit, see table 3.1 for details, after thermal balance has been attained
the equipment shall be switched on in the transmit condition for half an hour after which the appropriate
tests shall be carried out.
For tests at the lower temperature, see table 3.1 for details, after thermal balance has been attained the
equipment shall be switched on in the receive or transmit condition for one minute after which the
appropriate tests shall be carried out. If the equipment contains temperature stabilisation circuits
designed to operate continuously, the equipment may be switched on for 15 minutes before
measurements are made.
A 1.2
Equipment designed for intermittent operation
For tests at the upper temperature the equipment shall be placed in the test chamber and left until
thermal balance is attained. The equipment shall then be switched on for one minute in the transmit
condition, followed by four minutes in the receive condition after which the equipment shall meet the
specified requirements. For tests at the lower temperature the equipment shall be left in the test chamber
until thermal balance is attained, then switched to the standby or receive conditions for one minute after
which the equipment shall meet the specified requirements.
Arrangements for Test Signals at the Input to the Receiver
Test signal sources which are applied to the receiver shall present an impedance of 50 ohms to the
receiver input. This requirement shall be met irrespective whether one or more signals using a combining
network are applied to the receiver simultaneously.
The effects of any intermodulation products and noise produced in the test signal sources shall be
negligible.
Page 15 of 18
VNS 2111 Issue 1:
Receiver Mute or Squelch Facility
If the receiver is equipped with a mute or squelch circuit, this shall be made inoperative for the duration of
the type approval tests.
Receiver Rated Audio Output Power
The rated audio output power shall be the maximum power, declared by the manufacturer, for which all
the requirements of this specification are met. With normal test modulation the audio output power shall
be measured in a resistive load simulating the load with which the receiver normally operates.
Normal Test Modulation
For normal test modulation, the modulation frequency shall be 1 kHz and the resulting frequency
deviation shall be  1.5 kHz. The test signal shall be substantially free from amplitude modulation.
Transmitter Artificial Load
Tests on the transmitter shall be carried out using a non-reactive and non-radiating load of 50 ohms
connected to the transmitter radio frequency output port.
Measuring Frequency Error
The transmitter output shall be connected to an artificial load (clause A.8) and operated in accordance
with the manufacturer’s instructions. The emission shall be monitored by a frequency counter and the
carrier frequency shall be measured in the absence of modulation. The measurements shall be made
under normal test conditions, see table 3.1 for details, and repeated under extreme test conditions, see
table 3.1 for details.
Carrier Power Measurement
The transmitter output port shall be connected to an artificial load (clause A.8) with means of measuring
the power delivered to this load. In the absence of modulation, the transmitter shall be operated in
accordance with the manufacturer’s instructions. The carrier power shall be set to the manufacturer’s
maximum rated output.
The measurement shall be made under normal test conditions, see table 3.1 for details, and repeated
under extreme test conditions, see table 3.1 for details.
Maximum Permissible Frequency Deviation Measurement
The transmitter output shall be connected to an artificial load (clause A.8) and operated in accordance
with the manufacturer’s instructions. The emission shall be monitored by a modulation meter, capable of
measuring the peak value of both positive and negative frequency deviation, including that due to any
harmonics and intermodulation products which may be produced in the transmitter. The transmitter shall
then be modulated by an audio frequency signal 20dB above the level necessary to produce normal test
modulation (clause A.7) and the modulation frequency from 300 Hz to 3 kHz. At each frequency the peak
deviation shall be measured.
Response of the Transmitter at Modulation Frequencies above 3 kHz
The transmitter shall be arranged as described in clause A.11 and modulated with normal test modulation
(clause A.7). With a constant input level of the modulation signal, the frequency shall be varied from 3
kHz to 12.5 kHz. At each test frequency, the resulting frequency deviation shall be measured.
Adjacent Channel Power
The transmitter output shall be connected to a power measuring receiver (clause 3.2.1) via a 50 ohm
attenuator, set to produce an appropriate level at the receiver input. The transmitter shall be operated at
Page 16 of 18
VNS 2111 Issue 1:
the carrier power, see table 3.1 for limits. The transmitter shall be modulated at 1.25 kHz at a level 20dB
above that required to produce 60% of the maximum permissible frequency deviation, see table 3.1 for
limits. The test receiver shall be tuned to the nominal frequency of such a transmitter and the receiver
attenuator adjusted to a value ‘p’ such that a meter reading, of the order of 5 dB above the receiver noise
level, is obtained. The test receiver shall then be tuned to the nominal frequency of the higher adjacent
channel and the receiver attenuator re-adjusted to a value ‘q’ such that the same meter reading is again
obtained. The ratio, in decibels, of the adjacent channel power to the carrier power is the difference
between the attenuator settings ‘p’ and ‘q’. The adjacent channel power shall be determined by applying
this ratio to the carrier power as detailed in table 3.1. The measurement shall be repeated for the lower
adjacent channel.
Transmitter Spurious emission Measurement
The transmitter output shall be connected to either a spectrum analyser via an attenuator, or an artificial
load, with means of monitoring the emission with the spectrum analyser or selective voltmeter. The
transmitter shall be un-modulated and at each spurious emission in the frequency range given in table 3.1
the level of emission shall be measured relative to the carrier emission. The power level of each
emission shall be determined by applying the ratio measured to the carrier power level determined in
clause A.10.
Reference Sensitivity Measurement
A test signal at the nominal frequency of the receiver and with normal test modulation (clause A.7) shall
be applied to the input of the receiver via the standard input network according to clause A.4, at a level of
–124 dBW. The receiver shall then be adjusted for standard power output according to clause A.6. With
modulation removed the un-weighted signal to noise ratio shall be measured at the receiver output.
Adjacent Channel Selectivity
A test signal at the nominal frequency of the receiver and with normal test modulation (clause A.7) shall
be applied to the input of the receiver via one path of a combining unit . This signal constitutes the
wanted signal. A second test signal shall be applied to the receiver via the second path of the combining
unit. This test signal shall be set to the carrier frequency to the upper adjacent channel and shall be
modulated with a frequency of 400Hz at a deviation of  2.5kHz. This signal constitutes the unwanted
signal. In the absence of the unwanted signal the reference sensitivity shall be obtained as described in
clause A.15. The unwanted signal shall then be applied at a level of –74 dBW at the receiver input. The
un-weighted signal to noise ratio at the output of the receiver shall be measured. This measurement shall
be repeated using the frequency of the lower adjacent channel. These measurements shall be made
under normal test conditions and repeated under extreme test conditions (see table 3.1 for test condition
limits).
Spurious Response Rejection
A standard test signal according to clause A.7 shall be applied through the standard input network
according to clause A.4 to the receiver input at a level of –64 dBW, and its frequency varied from the
lowest intermediate frequency of the receiver to 2 GHz. At each frequency at which a response is
obtained the un-weighted signal to noise ratio at the output of the receiver shall be measured.
Receiver Spurious Emissions measurement
The receiver input port shall be connected to either a spectrum analyser or a selective voltmeter via an
attenuator or an artificial load with means of monitoring the emission with a spectrum analyser or a
selective voltmeter. At each emission up to 2 GHz the power level of the emission shall be measured.
Antenna Testing
A 1.3
Polarisation
Measurement of this characteristic shall be made under “free space” conditions.
Page 17 of 18
VNS 2111 Issue 1:
Document history
Draft
Date
Changes
Radiocommunications Agency
General Enquiries to the
Technical Enquiries to the
Information and Library Service:
Fixed Terrestrial and Satellite Links Unit:
Tel.: +44-(0) 207-211-0502 or 0505
Tel.: +44-(0)207-211-0300
Fax: +44 (0) 207-211- 0507
Fax: +44-(0)207-211- 0113
Email: library@ra.gsi.gov.uk
Email: fluhd@ra.gsi.gov.uk
Web site: www.radio.gov.uk
This is a UK Voluntary National Standard
There is no current published version of this UK VNS.
Postal address:
Fixed Terrestrial and Satellite Links Unit, Wyndham House, 189 Marsh Wall, LONDON, E14 9SX
Page 18 of 18