CXtec NEW COMPATIBLE 2.2 DBI RUBBER DUCK ANTENNA WITH RPTNC FEMALE Guia De Especificaciones
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below 30 dBm the antenna may be increased from the initial 6dBi, by 3 dB. (29 dB transmitter means 9dBi antenna, 28 dB transmitter means
12dBi antenna). Because we are operating at 20 dBm, which is 10 dB below the 30 dBm level, we can increase the out antenna by 30 dB. Note
that Cisco has never tested, and therefore is not certified, with any antenna larger than 21dBi.
The main issue that comes to question here is, what differentiates a point-to-point from a multipoint system.
In Figure 8, point A communicates to a single point, B, and point B communicates to a single point A; therefore, it is simple to see that both
locations see this as a point-to-point installation.
In Figure 9, point A communicates to more than one (or multiple) points; therefore, point A is operating in a multipoint configuration, and the
largest antenna permitted is 16dBi. Point B or point C can each communicate to only one point, (point A); therefore, point B and point C actually
operate in a single-point or point-to-point operation, and a larger antenna may be used.
Figure 8. Point-to-Point Wireless Bridge Solution
Figure 9. Point-to-Multipoint Wireless Bridge Solution
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Amplifiers—The FCC Rules, Section 15.204-Part C, states “External radio frequency power amplifiers shall not be marketed as separate
products...” Part D states “Only the antenna with which an intentional radiator (transmitter) is originally authorized may be used with the
intentional radiator." This means that unless the amplifier manufacturer submits the amplifier for testing with the radio and antenna, it cannot
be sold in the U.S. If it has been certified, then it must be marketed and sold as a complete system, including transmitter, antenna, and coax.
It also must be installed exactly this way.
intentional radiator." This means that unless the amplifier manufacturer submits the amplifier for testing with the radio and antenna, it cannot
be sold in the U.S. If it has been certified, then it must be marketed and sold as a complete system, including transmitter, antenna, and coax.
It also must be installed exactly this way.
If using a system that includes an amplifier, remember that the above rules concerning power are still in effect. If the amplifier is 1/2 watt
(27 dBm), this means in a multipoint system the maximum antenna gain is only 9dBi, and in a point-to-point system it is only 15dBi.
ETSI
The European Telecommunication Standardization Institute (ETSI) has developed standards that have been adopted by many European countries
as well as many others. Under the ETSI regulations, the power output and EIRP regulations are much different than in the U.S.
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Antenna Gain and Power Output—The ETSI regulations specify maximum EIRP as 20 dBm. Since this includes antenna gain, this limits
the antennas that can be used with a transmitter. To use a larger antenna, the transmitter power must be reduced so that the overall gain of the