User's Manual

Installation 41
2-6.16 Two Sector Six TRX (S42) Configuration
This is a 25 watt (44 dBm) four antenna configuration available in either 850 MHz or 900 MHz
frequencies. This configuration has two sectors with four TRXs in one sector and two TRXs in the other
sector.
• Connect your antennas as shown in Figure 2-29.
2-6.17 RF Radiation Hazard
As of October 15, 1997, all products must address the issue of Human Exposure to RF electromagnetic
fields. Referring to OET Bulletin 65, RF radiation limits for the 300 - 1500 MHz range are f / 300 mW/
cm2 for occupational exposure, and f / 1500 mW/cm2 for general population exposure (where f is
frequency in MHz). At the 869 MHz cellular band these limits are 2.90 mW/cm2 for occupational
exposure, and 0.58 mW/cm2 for general population exposure.
The Ultrawave base station may consist of up to six separate transceivers, with each of the transmitters
operating at a maximum output power of +47 dBm (50W). The Ultrawave base station transmitters
operate in the U.S. cellular band of 869 to 894 MHz.
As the Ultrawave is intended to be operated in cellular service, each of its transmitters is typically
connected to a 65 - 120 degree sector antenna or omni directional antenna. For the purpose of the
MPE calculations, it will be assumed that the Ultrawave is fully equipped with six transceivers, and that
two different transmitters are used in each 120 degree sector. For the MPE calculations this would be
the worst case radiation levels as the equivalent RF power of +50 dBm (100W) would be transmitted
into a 120 degree sector.
The typical gain of 65 - 120 degree sector antenna is in the range of +6 to +18 dBi. However, there is
the highest ERP limitation on the Part22 requirement which is 500W(57 dBd).
The duty cycle of the transmitter is 100%. Assuming two transmitters are operating into the same 120
degree sector, a maximum of +47 dBm of RF energy would be transmitted into two antennas, with total
EIRP=61 dBi would be the worst case.
Figure 2-29 Antenna Cabling for S42 Configuration
ANT ANT
ANT
DIV
ANT
MAIN
RF modules
IW009309
Internal RF connector
External RF connector
Antenna 1
Diversity
Antenna connection
1 2 3 4 50
Not Used Not Used
Antenna 1
Main
Antenna 2
Main
Antenna 2
Diversity