6. EMC Compliance
6.1 Introduction
Compliance of the fundamental and harmonic levels of the BRD4174B Radio Board is tested against the following standards:
• 169.4 MHz:
• ETSI EN 300-220-1
• 2.4 GHz:
• ETSI EN 300-328
• FCC 15.247
6.2 EMC Regulations for 169.4 MHz
6.2.1 ETSI EN 300-200-1 Emission Limits for the 169.4-169.475 MHz Band
Based on ETSI EN 300-220-1 the allowed maximum fundamental power for the 169.4-169.475 MHz band is 500 mW (27 dBm) e.r.p.
both for conducted and radiated measurements.
Note:
Further in this document EIRP (Effective Isotropic Radiated Power) will be used instead of e.r.p. (Effective Radiated Power) for
the comparison of the radiated limits and measurement results. The 500 mW e.r.p radiated limit is equivalent to 29.1 dBm EIRP.
For the unwanted emission limits see the table below.
Table 6.1. ETSI EN 300-220-1 Spurious Domain Emission Limits in e.r.p. (and EIRP)
Frequency
47 MHz to 74 MHz
87.5 MHz to 118 MHz
174 MHz to 230 MHz
470 MHz to 862 MHz
Other frequencies
below 1000 MHz
Frequencies
above 1000 MHz
Operating
4 nW (-54 dBm e.r.p. = -51.8 dBm
EIRP)
250 nW (-36 dBm e.r.p. = -33.9 dBm
EIRP)
1 uW (-30 dBm e.r.p. = -27.9 dBm
EIRP)
Standby
2 nW (-57 dBm e.r.p. = -54.8 dBm
EIRP)
2 nW (-57 dBm e.r.p. = -54.8 dBm
EIRP)
20 nW (-47 dBm e.r.p. = -44.8 dBm
EIRP)
The above ETSI limits are also applied both for conducted and radiated measurements.
6.3 ETSI EN 300-328 Emission Limits for the 2400-2483.5 MHz Band
Based on ETSI EN 300-328, the allowed maximum fundamental power for the 2400-2483.5 MHz band is 20 dBm EIRP. For the unwan-
ted emissions in the 1 GHz to 12.75 GHz domain, the specific limit is -30 dBm EIRP.
6.4 FCC15.247 Emission Limits for the 2400-2483.5 MHz Band
FCC 15.247 allows conducted output power up to 1 Watt (30 dBm) in the 2400-2483.5 MHz band. For spurious emissions the limit is
-20 dBc based on either conducted or radiated measurement, if the emission is not in a restricted band. The restricted bands are speci-
fied in FCC 15.205. In these bands the spurious emission levels must meet the levels set out in FCC 15.209. In the range from
960 MHz to the frequency of the 5th harmonic, it is defined as 0.5 mV/m at 3 m distance which equals to -41.2 dBm in EIRP.
Additionally, for spurious frequencies above 1 GHz, FCC 15.35 allows duty-cycle relaxation to the regulatory limits. For the EmberZNet
PRO the relaxation is 3.6 dB. Therefore, the -41.2 dBm limit can be modified to -37.6 dBm.
If operating in the 2400-2483.5 MHz band, the 2nd, 3rd, and 5th harmonics can fall into restricted bands. As a result, for those harmon-
ics the -37.6 dBm limit should be applied. For the 4th harmonic the -20 dBc limit should be applied.
BRD4174B Reference Manual
EMC Compliance
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