APPENDIX 3 (Rev.WRC-03)
Tables of
maximum permitted power levels for spurious
or spurious domain emissions
1 The following sections indicate the maximum permitted levels of certain unwanted emissions, in terms of power as indicated in the tables, of components supplied by a transmitter to the antenna transmission line. Section I, which provides spurious emission limits, is applicable until 1 January 2012 to transmitters installed on or before 1 January 2003; Section II, which limits emissions in the spurious domain, is applicable to transmitters installed after 1 January 2003 and to all transmitters after 1 January 2012. The provisions of No. 4.5 apply to unwanted emissions not covered in Sections I and II.
2 Spurious and spurious domain emissions (covered by Sections I and II) from any part of the installation, other than the antenna and its transmission line, shall not have an effect greater than would occur if this antenna system were supplied with the maximum permitted power at the frequency of that emission.
3 These levels shall not, however, apply to emergency position-indicating radiobeacon (EPIRB) stations, emergency locator transmitters, ships’ emergency transmitters, lifeboat transmitters, survival craft stations or maritime transmitters when used in emergency situations.
4 For technical or operational reasons, more stringent levels than those specified may be applied to protect specific services in certain frequency bands. The levels applied to protect these services, such as safety and passive services, shall be those agreed upon by the appropriate world radiocommunication conference. More stringent levels may also be fixed by specific agreement between the administrations concerned. Additionally, special consideration of transmitter spurious or spurious domain emissions may be required for the protection of safety services, radio astronomy and space services using passive sensors. Information on the levels of interference detrimental to radio astronomy, Earth exploration satellites and meteorological passive sensing is given in the most recent version of Recommendation ITU‑R SM.329.
5 Spurious and spurious domain emission limits (covered by Sections I and II) for combined radiocommunication and information technology equipment are those for the radiocommunication transmitters. (WRC‑03)
Section I – Spurious emission
limits for transmitters installed on
or before 1 January 2003 (valid until 1 January 2012)
6 Radar systems are exempt from spurious emission limits under this Section. The lowest practicable power of spurious emission should be achieved. (WRC‑2000)
TABLE I
Attenuation values and absolute
mean power levels used to calculate maximum
permitted spurious emission power levels for use with radio equipment
|
Frequency band containing
the assignment |
For any spurious component, the attenuation (mean power within the necessary bandwidth relative to the mean power of the spurious component concerned) shall be at least that specified below and the absolute mean power levels given shall not be exceeded1 |
|
9 kHz to 30 MHz |
40
dB |
|
30 MHz to 235 MHz |
|
|
– mean power above 25 W |
60 dB |
|
– mean power 25 W or less |
40
dB |
|
235 MHz to 960 MHz |
|
|
– mean power above 25 W |
60 dB |
|
– mean power 25 W or less |
40
dB |
|
960 MHz to 17.7 GHz |
|
|
– mean power above 10 W |
50 dB |
|
– mean power 10 W or less |
100 mW 6, 7, 8, 9 |
|
Above 17.7 GHz |
The lowest possible values achievable shall be employed (see Recommendation 66 (Rev.WRC-2000)*). |
|
1 When checking compliance with the provisions of the Table, it shall be verified that the bandwidth of the measuring equipment is sufficiently wide to accept all significant components of the spurious emission concerned. 2 For mobile transmitters which operate below 30 MHz, any spurious component shall have an attenuation of at least 40 dB without exceeding the value of 200 mW, but every effort should be made to comply with the level of 50 mW wherever practicable. 3 For transmitters of a mean power exceeding 50 kW which can operate on two or more frequencies covering a frequency range approaching an octave or more, while a reduction below 50 mW is not mandatory, a minimum attenuation of 60 dB shall be provided. |
|
TABLE I (end)
|
4 For hand-portable equipment of mean power less than 5 W, the attenuation shall be 30 dB, but every practicable effort should be made to attain 40 dB attenuation. 5 Administrations may adopt a level of 10 mW provided that harmful interference is not caused. 6 Where several transmitters feed a common antenna or closely spaced antennas on neighbouring frequencies, every practicable effort should be made to comply with the levels specified. 7 Since these levels may not provide adequate protection for receiving stations in the radio astronomy and space services, more stringent levels might be considered in each individual case in the light of the geographical position of the stations concerned. 8 These levels are not applicable to systems using digital modulation techniques, but may be used as a guide. Values for these systems may be provided by the relevant ITU‑R Recommendations, when available (see Recommendation 66 (Rev.WRC-2000)*). 9 These levels are not applicable to stations in the space services, but the levels of their spurious emissions should be reduced to the lowest possible values compatible with the technical and economic constraints to which the equipment is subject. Values for these systems may be provided by the relevant ITU-R Recommendations, when available (see Recommendation 66 Rev.WRC-2000)*). * Note by the Secretariat: This Recommendation was abrogated by WRC-03. |
Section II – Spurious domain emission limits for transmitters installed after 1 January 2003 and for all transmitters after 1 January 2012 (WRC‑03)
Application of these limits
7 The frequency range of the measurement of spurious domain emissions is from 9 kHz to 110 GHz or the second harmonic if higher. (WRC‑03)
8 Except as provided in § 9 and 10 of this Appendix, the spurious domain emission levels are specified in the following reference bandwidths:
– 1 kHz between 9 kHz and 150 kHz
– 10 kHz between 150 kHz and 30 MHz
– 100 kHz between 30 MHz and 1 GHz
– 1 MHz above 1 GHz. (WRC‑03)
9 The reference bandwidth of all space service spurious domain emissions should be 4 kHz. (WRC‑03)
10 For radar systems, the reference bandwidths for specifying spurious domain emission levels should be calculated for each particular system. Thus, for the four general types of radar pulse modulation utilized for radionavigation, radiolocation, acquisition, tracking and other radiodetermination functions, the reference bandwidth values are determined using the following:
– for a fixed-frequency, non-pulse-coded radar, the reciprocal of the radar pulse length, in seconds (e.g. if the radar pulse length is 1 ms, then the reference bandwidth is 1/(1 ms) = 1 MHz);
– for a fixed-frequency, phase-coded pulsed radar, the reciprocal of the phase chip length, in seconds (e.g. if the phase-coded chip is 2 ms long, then the reference bandwidth is 1/(2 ms) = 500 kHz);
– for a frequency modulated (FM) or chirped radar, the square root of the quantity obtained by dividing the chirp bandwidth in MHz by the pulse length, in ms (e.g. if the FM is from 1 250 MHz to 1 280 MHz, i.e. 30 MHz, during the pulse length of 10 ms, then the reference bandwidth is (30 MHz/10 ms)1/2 = 1.73 MHz);
– for radars operating with multiple waveforms, the reference bandwidth for specifying spurious domain emission levels is determined empirically from observations of the radar emission and is obtained following the guidance given in the most recent version of Recommendation ITU‑R M.1177.
In the case of radars, for which the bandwidth, as determined using the method above, is greater than 1 MHz, a reference bandwidth of 1 MHz should be used. (WRC‑03)
10bis Guidance regarding the methods of measuring spurious domain emissions is given in the most recent version of Recommendation ITU‑R SM.329. The e.i.r.p. method specified in this Recommendation should be used when it is not possible to accurately measure the power supplied to the antenna transmission line, or for specific applications where the antenna is designed to provide significant attenuation in the spurious domain. Additionally, the e.i.r.p. method may need some modification for special cases. Specific guidance regarding the methods of measuring spurious domain emissions from radar systems is given in the most recent version of Recommendation ITU‑R M.1177.
To improve measurement accuracy, sensitivity and efficiency, the resolution bandwidth in which spurious domain emissions are measured can be different from the reference bandwidth used for specifying spurious domain emission levels. (WRC‑03)
11 The emission limits of this Section apply to all emissions, including harmonic emissions, intermodulation products, frequency conversion products and parasitic emissions, at frequencies in the spurious domain (see Fig. 1). The upper and lower parts of the spurious domain extend outward from a boundary determined using Annex 1. (WRC‑03)

11bis (SUP - WRC-03)
11ter For the case of a single satellite operating with more than one transponder in the same service area, and when considering the limits for spurious domain emissions as indicated in § 11 of this Appendix, spurious domain emissions from one transponder may fall on a frequency at which a second, companion transponder is transmitting. In these situations, the level of spurious domain emissions from the first transponder is well exceeded by the fundamental or out-of-band domain emissions of the second transponder. Therefore, the limits of this Appendix should not apply to those emissions of a satellite that fall within either the necessary bandwidth or the out-of-band domain of another transponder on the same satellite, in the same service area (see Fig. 2). (WRC‑03)

Transponders A, B, C and D are operating on the same satellite in the same service area. Transponder A is not required to meet spurious domain emission limits in frequency ranges ¨ and ¸, but is required to meet them in frequency ranges and . (WRC‑03)
Where specified in relation to mean power, spurious domain emissions are to be at least x dB below the total mean power P, i.e. – x dBc. The power P (W) is to be measured in a bandwidth wide enough to include the total mean power. The spurious domain emissions are to be measured in the reference bandwidths given in the relevant ITU‑R Recommendations. The measurement of the spurious domain emission power is independent of the value of necessary bandwidth. Because the absolute emission power limit, derived from 43 + 10 log (P), can become too stringent for high-power transmitters, alternative relative powers are also provided in Table II.
Example 1
A land mobile transmitter, with any value of necessary bandwidth, must meet a spurious domain emission attenuation of 43 + 10 log (P), or 70 dBc, whichever is less stringent. The reference bandwidths used for specifying spurious domain emission levels are provided in § 8 to 10 of this Appendix. Applying this in the frequency range between 30 MHz and 1 GHz gives a reference bandwidth of 100 kHz.
With a measured total mean power of 10 W:
– Attenuation relative to total mean power = 43 + 10 log (10) = 53 dBc.
– The 53 dBc value is less stringent than the 70 dBc, so the 53 dBc value is used.
– Therefore: Spurious domain emissions must not exceed 53 dBc in a 100 kHz bandwidth, or converting to an absolute level, they must not exceed 10 dBW – 53 dBc = –43 dBW in a 100 kHz reference bandwidth.
With a measured total mean power of 1 000 W:
– Attenuation relative to total mean power = 43 + 10 log (1 000) = 73 dBc.
– The 73 dBc value is more stringent than the 70 dBc limit, so the 70 dBc value is used.
– Therefore: Spurious domain emissions must not exceed 70 dBc in a 100 kHz bandwidth, or converting to an absolute level, they must not exceed 30 dBW – 70 dBc = _ 40 dBW in a 100 kHz reference bandwidth. (WRC‑03)
Example 2
A space service
transmitter with any value of necessary bandwidth must meet a spurious domain
emission attenuation of 43 + 10 log (P),
or 60 dBc, whichever is less stringent. To measure
spurious domain emissions at any frequency, Note 10 to Table II indicates
using a reference bandwidth of 4 kHz.
With a measured total mean power of 20 W:
– Attenuation relative to total mean power = 43 + 10 log (20) = 56 dBc.
– The 56 dBc value is less stringent than the 60 dBc limit, so the 56 dBc value is used.
– Therefore: Spurious domain emissions must not exceed 56 dBc in a 4 kHz reference bandwidth, or converting to an absolute level, they must not exceed 13 dBW – 56 dBc = _ 43 dBW in a 4 kHz reference bandwidth. (WRC‑03)
TABLE II (WRC‑03)
Attenuation values used to calculate maximum permitted
spurious domain emission power levels for
use with radio equipment
|
Service category
in accordance with |
Attenuation (dB)
below the power |
|
All services except those services quoted below: |
43 + 10 log (P), or 70 dBc, whichever is less stringent |
|
Space services (earth stations)10, 16 |
43 + 10 log (P), or 60 dBc, whichever is less stringent |
|
Space services (space stations)10, 17 |
43 + 10 log (P), or 60 dBc, whichever is less stringent |
|
Radiodetermination14 |
43 + 10 log (PEP), or 60 dB, whichever is less stringent |
|
Broadcast television11 |
46 + 10 log (P), or 60 dBc, whichever is less stringent, without exceeding the absolute mean power level of 1 mW for VHF stations or 12 mW for UHF stations. However, greater attenuation may be necessary on a case by case basis |
|
Broadcast FM |
46 + 10 log (P), or 70 dBc, whichever is less stringent; the absolute mean power level of 1 mW should not be exceeded |
|
Broadcasting at MF/HF |
50 dBc; the absolute mean power level of 50 mW
should |
|
SSB from mobile stations12 |
43 dB below PEP |
|
Amateur services operating below 30 MHz (including those using SSB)16 |
43 + 10 log (PEP), or 50 dB, whichever is less stringent |
|
Services operating below 30 MHz, except space, radiodetermination, broadcast, those using SSB from mobile stations, and amateur12 |
43 + 10 log (X), or 60 dBc, whichever is less stringent, where X = PEP for SSB modulation, and X = P for other modulation |
|
Low-power device radio equipment13 |
56 + 10 log (P), or 40 dBc, whichever is less stringent |
|
Emergency transmitters18 |
No limit |
TABLE II (end) (WRC-03)
|
P: mean power in watts supplied to the antenna transmission line, in accordance with No. 1.158. When burst transmission is used, the mean power P and the mean power of any spurious domain emissions are measured using power averaging over the burst duration. PEP: peak envelope power in watts supplied to the antenna transmission line, in accordance with No. 1.157. dBc: decibels relative to the unmodulated carrier power of the emission. In the cases which do not have a carrier, for example in some digital modulation schemes where the carrier is not accessible for measurement, the reference level equivalent to dBc is decibels relative to the mean power P. 10 Spurious domain emission limits for all space services are stated in a 4 kHz reference bandwidth. |
|
|
11 For analogue television transmissions, the mean power level is defined with a specified video signal modulation. This video signal has to be chosen in such a way that the maximum mean power level (e.g. at the video signal blanking level for negatively modulated television systems) is supplied to the antenna transmission line. 12 All classes of emission using SSB are included in the category “SSB”. 13 Low-power radio devices having a maximum output power of less than 100 mW and intended for short-range communication or control purposes; such equipment is in general exempt from individual licensing. 14 For radiodetermination systems (radar as defined by No. 1.100), spurious domain emission attenuation (dB) shall be determined for radiated emission levels, and not at the antenna transmission line. The measurement methods for determining the radiated spurious domain emission levels from radar systems should be guided by the most recent version of Recommendation ITU‑R M.1177. (WRC‑03) 15 In some cases of digital modulation (including digital broadcasting), broadband systems, pulsed modulation and narrow-band high-power transmitters for all categories of services, there may be difficulties in meeting limits close to ± 250% of the necessary bandwidth. 16 Earth stations in the amateur-satellite service operating below 30 MHz are in the service category “Amateur services operating below 30 MHz (including those using SSB)”. (WRC‑2000) 17 Space stations in the space research service intended for operation in deep space as defined by No. 1.177 are exempt from spurious domain emission limits. (WRC‑03) 18 Emergency position-indicating radio beacon, emergency locator transmitters, personal location beacons, search and rescue transponders, ship emergency, lifeboat and survival craft transmitters and emergency land, aeronautical or maritime transmitters. (WRC‑2000) |
|
ANNEX 1 (WRC‑03)
Determination
of the boundary between the
out-of-band and spurious domains
1 Except as
provided below, the boundary between the out-of-band and spurious domains
occurs at frequencies that are separated from the centre frequency of the
emission by the values shown in Table 1. In general, the boundary, on
either side of the centre frequency, occurs at a separation of 250% of the
necessary bandwidth, or at 2.5 BN, as shown in
Table 1. For most systems, the centre frequency of the emission is the
centre of the necessary bandwidth. For multichannel or multicarrier
transmitters/transponders, where several carriers may be transmitted
simultaneously from a final output amplifier or an active antenna, the centre
frequency of the
emission is taken to be the centre of the –3 dB bandwidth of the
transmitter or transponder, and the transmitter or transponder bandwidth is
used in place of the necessary bandwidth for determining the boundary. For
multicarrier satellite systems, guidance on the boundary between the
out-of-band and spurious domains is provided in the most recent version of
Recommendation ITU‑R SM.1541. Some systems specify unwanted
emissions relative to channel bandwidth, or channel spacing. These may be used
as a substitute for the necessary bandwidth in Table 1, provided they are
found in ITU‑R Recommendations.
TABLE 1
Values for frequency
separation between the centre frequency
and the boundary of the spurious domain
|
Frequency |
Narrow-band case |
Normal |
Wideband case |
||
|
for BN < |
Separation |
for BN > |
Separation |
||
|
9 kHz < fc £ 150 kHz |
250 Hz |
625 Hz |
2.5 BN |
10 kHz |
1.5 BN + 10 kHz |
|
150 kHz < fc £ 30 MHz |
4 kHz |
10 kHz |
2.5 BN |
100 kHz |
1.5 BN + 100 kHz |
|
30 MHz < fc £ 1 GHz |
25 kHz |
62.5 kHz |
2.5 BN |
10 MHz |
1.5 BN + 10 MHz |
|
1 GHz < fc £ 3 GHz |
100 kHz |
250 kHz |
2.5 BN |
50 MHz |
1.5 BN + 50 MHz |
|
3 GHz < fc £ 10 GHz |
100 kHz |
250 kHz |
2.5 BN |
100 MHz |
1.5 BN + 100 MHz |
|
10 GHz < fc £ 15 GHz |
300 kHz |
750 kHz |
2.5 BN |
250 MHz |
1.5 BN + 250 MHz |
|
15 GHz < fc £ 26 GHz |
500 kHz |
1.25 MHz |
2.5 BN |
500 MHz |
1.5 BN + 500 MHz |
|
fc > 26 GHz |
1 MHz |
2.5 MHz |
2.5 BN |
500 MHz |
1.5 BN + 500 MHz |
|
NOTE – In Table 1, fc is the centre frequency of the emission and BN is the necessary bandwidth. If the assigned frequency band of the emissions extends across two frequency ranges, then the values corresponding to the higher frequency range shall be used for determining the boundary. |
|||||
Example 1: The necessary bandwidth of an emission at 26 MHz is 1.8 kHz. Since BN is less than 4 kHz, the minimum separation of 10 kHz applies. The spurious domain begins 10 kHz each side of the centre of the necessary bandwidth.
Example 2: The necessary bandwidth of an emission at 8 GHz is 200 MHz. Since the wideband case applies for BN > 100 MHz at that frequency, the spurious domain begins 1.5 ´ 200 MHz + 100 MHz = 400 MHz each side of the centre of the necessary bandwidth. Using the general separation formula, the out-of-band domain would have extended to 2.5 ´ 200 MHz = 500 MHz either side of the centre frequency.
2 Tables 2 and 3 show exceptions to Table 1 for narrow-band and wideband cases, respectively, applicable to particular systems or services and frequency bands.
TABLE 2
Narrow-band variations for particular systems or services and frequency bands
|
System or service |
Frequency range |
Narrow-band case |
||
|
for BN
< |
Separation |
|||
|
Fixed service |
14 kHz-1.5 MHz |
20 |
50(1) |
|
|
1.5-30 MHz |
PT ≤ 50 W |
30 |
75(2) |
|
|
PT > 50 W |
80 |
200(2) |
||
|
(1) The separation value is based on an assumption that the maximum value of the necessary bandwidth is about 3 kHz for the frequency range 14 kHz-1.5 MHz. The separation value of 50 kHz is extremely large as compared with the necessary bandwidth. This is because unwanted emissions of high power transmitters under modulated conditions have to be below the spurious limit (70 dBc) at the boundary between the out-of-band and spurious domains. (2) PT is the transmitter power. The separation values are based on an assumption that the maximum value of the necessary bandwidth is about 12 kHz for the frequency range 1.5-30 MHz. The separation value of 200 kHz for PT > 50 W is extremely large as compared with the necessary bandwidth. This is because unwanted emissions of high power transmitters under modulated conditions have to be below the spurious limit, 70 dBc, at the boundary between the out-of-band and spurious domains. Also, if future systems in the fixed service operating in this frequency range require a necessary bandwidth larger than 12 kHz, it may become necessary to review the 200 kHz separation. |
||||
TABLE 3
Wideband variations for particular systems or services and frequency bands
|
System or service |
Frequency range |
Wideband case |
|
|
For BN > |
Separation |
||
|
Fixed service |
14-150 kHz |
20 kHz |
1.5 BN + 20 kHz |
|
Fixed-satellite |
3.4-4.2 GHz |
250 MHz |
1.5 BN + 250 MHz |
|
FSS |
5.725-6.725 GHz |
500 MHz |
1.5 BN + 500 MHz |
|
FSS |
7.25-7.75 GHz and 7.9-8.4 GHz |
250 MHz |
1.5 BN + 250 MHz |
|
FSS |
10.7-12.75 GHz |
500 MHz |
1.5 BN + 500 MHz |
|
Broadcasting-satellite service |
11.7-12.75 GHz |
500 MHz |
1.5 BN + 500 MHz |
|
FSS |
12.75-13.25 GHz |
500 MHz |
1.5 BN + 500 MHz |
|
FSS |
13.75-14.8 GHz |
500 MHz |
1.5 BN + 500 MHz |
3 For primary radar, the boundary between the out-of-band and spurious domains is the frequency at which the out-of-band domain limits specified in the applicable ITU-R Recommendations are equal to the spurious domain limit defined in Table II of this Appendix. Further guidance on the boundary between the out-of-band and spurious domains for primary radar is provided in the most recent version of Recommendation ITU-R SM.1541.