Recommendation itu-r sm. 329-9 Spurious emissions




Yüklə 368.62 Kb.
səhifə13/13
tarix10.04.2016
ölçüsü368.62 Kb.
1   ...   5   6   7   8   9   10   11   12   13
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. To measure spurious domain emissions in the frequency range between 30 and 1 000 MHz, further recommends 4.1 indicates use of a reference bandwidth of 100 kHz. For other frequency ranges, the measurement must use the appropriate reference bandwidths given in further recommends 4.1.

With a measured total mean power of 10 W:

Attenuation relative to total mean power  43  10 log 10  53 dB

The 53 dBc is less stringent than 70 dBc, so the 53 dBc value is used.

Therefore:

Spurious domain emissions must not exceed 53 dBc in a 100 kHz reference bandwidth, or converting to an absolute level

Spurious domain emissions 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 dB

The 73 dBc is more stringent than 70 dBc limit, so the 70 dBc value is used.

Therefore:

Spurious domain emissions must not exceed 70 dBc in a 100 kHz reference bandwidth, or converting to an absolute level

Spurious domain emissions must not exceed 30 dBW – 70 dBc  – 40 dBW in a 100 kHz reference bandwidth.


Example 2:

A space services 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, footnote(3) of Table 2 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 dB

The 56 dBc 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

Spurious domain emissions must not exceed 13 dBW – 56 dBc  – 43 dBW in a 4 kHz reference bandwidth.



TABLE 10

Absolute levels of spurious domain emissions – Category A


Service category in accordance
with RR Article 1 or
equipment type(1), (2)


Maximum permitted spurious domain emission
power in the relevant reference bandwidth
(see further recommends 4.1) (dBm)
with P, PEP or X (W)


All services except those services quoted below

–13 dBm if P  500 W
10 log P – 40 if P  500 W

Space services (mobile earth stations)(3), (4)

–13 dBm if P  50 W
10 log P – 30 if P  50 W

Space services (fixed earth stations)(3), (4)

–13 dBm if P  50 W
10 log P – 30 if P  50 W

Space services space stations(3), (5), (6)

–13 dBm if P  50 W
10 log P – 30 if P  50 W

Radiodetermination(7)

–13 dBm if PEP  50 W
10 log PEP – 30 if PEP  50 W

Broadcast TV(8)
VHF transmitters

–16 dBm if P  25 W
10 log P – 30 if 25 W  P  1 000 W
0 dBm if P  1 000 W

Broadcast TV(8)
UHF transmitters

–16 dBm if P  25 W
10 log P – 30 if 25 W  P  12 000 W
10.8 dBm if P  12 000 W

Broadcast FM

–16 dBm if P  250 W
10 log P – 40 if 250 W  P  10 000 W
0 dBm if P  10 000 W

Broadcast MF/HF

10 log P – 20 if P  5 000 W
17 dBm if P  5 000 W

SSB from mobile stations(9)

10 log PEP –13

Amateur services operating below 30 MHz (including with SSB)(9)

–13 dBm if PEP  5 W
10 log PEP – 20 if PEP  5 W

Services operating below 30 MHz,
except space, radiodetermination, broadcast, those using SSB from mobile stations,
and amateur(9)

–13 dBm if X  50 W
10 log X – 30 if X  50 W
where:

XPEP for SSB modulation


XP for other modulation

Low power device radio equipment(10)

–26 dBm if P  0.025 W
10 log P – 10 if 0.025 W  P  0.100 W

EPIRB, ELT, PLB, SART, ship emergency, lifeboat, and survival craft transmitters, land, aeronautical or maritime transmitters when used in emergency

No limit




Notes to Table 10:

P : mean power (W) at the antenna transmission line, in accordance with RR No. 1.158. When burst transmission is used, the mean power P and the mean power of any spurious emissions are measured using power averaging over the burst duration.

PEP : peak envelope power (W) at the antenna transmission line, in accordance with RR No. 1.157.

When the term P is used, both the power supplied to the antenna transmission line and spurious emissions should be evaluated in terms of mean power and mean power in the reference bandwidth respectively. When the term PEP is used, both the power supplied to the antenna transmission line and spurious emissions should be evaluated in terms of peak envelope power and peak envelope power in the reference bandwidth respectively. However, when measurement of spurious emission in terms of PEP is difficult due to the nature of spurious emission (e.g. Gaussian noise), it is allowed to evaluate both power supplied to the antenna transmission line and spurious emission power in terms of mean power (see Annex 2).



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.

(1) In some cases of digital 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.

(2) Use the e.i.r.p. method shown in Annex 2, § 3.3, when it is not practical to access the transition between the transmitter and the antenna transmission line.

(3) Spurious limits for all space services are stated in a 4 kHz reference bandwidth.

(4) Earth stations in the amateur-satellite service operating below 30 MHz are in the service category “Amateur services operating below 30 MHz (including with SSB)”.

(5) 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 Table 10, 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 should not apply to those spurious domain 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 RR Appendix 3).

(6) Space stations in the space research service intended for operation in deep space as defined by RR No. 1.177 are exempt from spurious limits.

(7) For radiodetermination systems (radar as defined by RR No. 1.100), spurious domain emission attenuation (dB) shall be determined for radiated emission levels, and not at the antenna transmission line. The measurement method for determining the radiated spurious domain emission levels from radar systems should be guided by Recommendation ITU R M.1177.

(8) 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 signals) is provided to the antenna transmission line.

(9) All classes of emission using SSB are included in the category SSB.

(10) Low power radio device 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.).

ANNEX 6


Reference bandwidth for Category B limits
Case of the fixed service

Analogue and digitally modulated radio-relays although generally providing a good spectrum efficiency, are unable to comply with the Category B limits for close-in frequencies due to the wideband noise generated by such systems. It is therefore necessary to provide generic steps of reference bandwidth in order to produce suitable transition area for the spectral density.

The generic reference mask is shown in Fig. 3, with breakpoints function of the channel separation (CS) or the necessary bandwidth (NB) referred to in Table 11.

TABLE 11


Generic spurious emission mask for Category B fixed service stations
(refer to Fig. 3)


Fundamental
emission
frequency


CS
(MHz)


Typical symbol frequency
(Mbit/s)


Ref. BW
0.3 kHz


Ref. BW
1 kHz


Ref. BW
10 kHz


Ref. BW
100 kHz


Fa
(MHz)


Fb
(MHz)


Fc
(MHz)


Fd
(MHz)


Below
21.2 GHz

0.01  CS  1

Fs  0.006  0.8





14

70

(terminal stations)

1  CS  10

Fs  0.6  8





28

70




CS  10

Fs   6





49(1)

70(1)

Below
21.2 GHz

0.01  CS  1

Fs  0.006  0.8

3.5

7

14

70

(other stations)

1  CS  10

Fs  0.6  8



14(1)

28

70




CS  10

Fs   6





49(1)

70(1)

Above 21.2 GHz

1  CS  10

Fs  0.6  8







70

(all stations)

CS  10

Fs   6









(1) Not applicable for CS which 250% exceed these values.

ANNEX 7


Reference bandwidth for Category B limits
Case of the land mobile service

Narrow-band analogue modulated systems of the land mobile service, with output power higher than 1 W and operated above 30 MHz, and digitally modulated systems of the land mobile service, although generally providing a good spectrum efficiency, are unable to comply with the Category B limits for close-in frequencies due to the wideband noise generated by such systems. It is therefore necessary to provide generic steps of reference bandwidth in order to produce suitable transition area for the spectral density.

The generic reference bandwidth mask is shown in Fig. 4, with breakpoints function of the CS or the NB referred to in Table 12, for frequencies below 1 GHz and in Fig. 5, with breakpoints function of the CS or the NB referred to in Table 13, for frequencies above 1 GHz.

These masks shall apply to both mobile terminals and base stations.



TABLE 12


Generic spurious emission mask for Category B land mobile service stations
(refer to Fig. 4)


Fa

100 kHz or 4 times NB, whichever is the greater

Fb

500 kHz or 10 times NB, whichever is the greater



TABLE 13


Generic spurious emission mask for Category B land mobile service stations
(refer to Fig. 5)


Fa

500 kHz or 10 times NB, whichever is the greater

Fb

1 MHz or 12 times NB, whichever is the greater



*The scope of this Recommendation is more exactly unwanted emissions in the spurious domain, since the limits also apply to any out of band emissions in the spurious domain, but do not apply to spurious emissions in the out of band domain

Note by the Editorial Committee – The terminology used in this Recommendation is in conformity, in the three working languages, with that of Article 1 of the Radio Regulations (RR) No. 1.145, namely:

– French: rayonnement non essentiel


– English: spurious emission
– Spanish: emisión no esencial.

1The terms “out-of-band domain” and “spurious domain” have been introduced in order to remove some inconsistency now existing between, on one hand, the definitions of the terms “out of band emission” and “spurious emission” in Article 1 of the RR and, on the other hand, the actual use of these terms in Appendix 3 of the RR, as revised by the World Radiocommunication Conference (Istanbul, 2000) (WRC 2000). Out of band and spurious limits apply, respectively, to all unwanted emissions in the out of band and spurious domains.
1   ...   5   6   7   8   9   10   11   12   13


Verilənlər bazası müəlliflik hüququ ilə müdafiə olunur ©azrefs.org 2016
rəhbərliyinə müraciət

    Ana səhifə