Справочник Пользователя для Wave Wireless Corporation 915B
TN138A
915B Radio Operational Requirements
Lawrence Gordon
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Last saved on 14-Sep-06 4:52 PM
F:\Tech Notes\TN138A - 915B Radio Operational Requirements.doc
2.5 Antennas
Only antennas that have been approved by FCC and IC shall be used with the 915B radio. This
means that any antenna of the same family with a gain less than or equal to the approved antenna
can be used.
The list of approved antennas is given in Appendix A, which will be updated as new antennas are
approved.
The 915B radio is approved for 27.3 dBm output power at the antenna port and FCC and IC rules
require the peak radiated power be no more than 36 dBm, so a maximum of 8.7 dB gain is
allowed for the antenna system, which includes the antenna gain in dBi and any losses between
the 915B radio and the antenna, including cable losses, insertion losses at filters and surge
protectors etc.
Therefore if a 12.15 dBi Dipole antenna is used, then the losses must be at least 3.45 dB (27.3 +
12.15 – 3.45 = 36 dBm). A rule of thumb is that the losses must equal Antenna Gain (dBi) – 8.7.
For antennas of the same type, but with less gain, the cable loss requirements can be reduced.
For example, a 9 dBi Dipole antenna would only require 0.3 dB cable loss.
This information shall be clearly noted in any installation manual for the final product.
It is also required that warnings be included in the installation manual regarding separation of
people from the antennas.
means that any antenna of the same family with a gain less than or equal to the approved antenna
can be used.
The list of approved antennas is given in Appendix A, which will be updated as new antennas are
approved.
The 915B radio is approved for 27.3 dBm output power at the antenna port and FCC and IC rules
require the peak radiated power be no more than 36 dBm, so a maximum of 8.7 dB gain is
allowed for the antenna system, which includes the antenna gain in dBi and any losses between
the 915B radio and the antenna, including cable losses, insertion losses at filters and surge
protectors etc.
Therefore if a 12.15 dBi Dipole antenna is used, then the losses must be at least 3.45 dB (27.3 +
12.15 – 3.45 = 36 dBm). A rule of thumb is that the losses must equal Antenna Gain (dBi) – 8.7.
For antennas of the same type, but with less gain, the cable loss requirements can be reduced.
For example, a 9 dBi Dipole antenna would only require 0.3 dB cable loss.
This information shall be clearly noted in any installation manual for the final product.
It is also required that warnings be included in the installation manual regarding separation of
people from the antennas.
• Indoor antennas are limited to gains of 7.5 dBi or less, including cable losses. This limts
the totoal EIRP to 34.8 dBm. Indoor antennas must be installed so that people are at least
20 cm from the antenna under normal conditions.
20 cm from the antenna under normal conditions.
• Outdoor antennas can support the full total gain of 8.7 dBi for the antenna system, for a
maximum EIRP of 36 dBm. Outdoor antennas must be installed so that people are
normally at least 30 cm from the antenna.
normally at least 30 cm from the antenna.
Antennas that support dual polarization, such as the dipole array (Til-tek TA-926VH-8-120 or
similar), can only be installed with one of the polarizations active at one time. For the Til-Tek
antenna, this means that the 915B radio can only be connected to one of the antenna ports.
similar), can only be installed with one of the polarizations active at one time. For the Til-Tek
antenna, this means that the 915B radio can only be connected to one of the antenna ports.
2.6 External RF Connectors
The 915B radio can be manufactured by Wave Wireless with a variety of external RF connection
options. The following requirements apply:
options. The following requirements apply:
• Wave Wireless proprietary, unique external connector – This connector is externally
accessible and can be used on any final product.
• No RF connector – Final products with an integrated, approved antenna (i.e. no RF
connector externally accessible).
• Standard external RF Connectors (e.g. SMA or N type) – Final products that have
standard externally accessible RF connectors can only be installed by professionals. The
installation guide for these products must make this clear. The guide must provide
sufficient instruction to the installer for a successful installation.
installation guide for these products must make this clear. The guide must provide
sufficient instruction to the installer for a successful installation.