Bird Technologies Group 61470A Benutzerhandbuch

Uplink output signals leave the channel module at
the UL OUT port. The signals are then passed on
to a power amplifier stage. The output of the power
amplifier is passed through a filter then radiated
from the donor antenna. Note: When the booster is
operated at the maximum uplink output power level
(+37 dBm) the gain of the donor antenna should be
limited to 0 dBi.

Downlink output signals leave the channel module
at the DL OUT port. The signals are then passed
on to a power amplifier stage. The output of the
power amplifier is passed through a filter then radi-
ated from the DAS antenna. Note: When the
booster is operated at the maximum downlink out-
put power level (+37 dBm) the gain of the DAS
antenna should be limited to 0 dBi. We recommend
the use of a Ceiling Mount DAS Antenna from Frac-
tal Antenna Systems inc. part # UACM.

The filter bandwidths can be programmed up to 3
MHz wide occupied bandwidth as long as operat-
ing in Class B mode. If in Class A mode the occu-
pied filter bandwidth is limited to 75 KHz.

Typically the filter bandwidth is usually kept small,
such as one of the predefined bandwidths of 12.5

KHz, 25 KHz, or 12.5 KHz low delay. In areas
where group delay is a concern the filter rejection
bandwidths or rejection amount can be modified
using the filter design tool.

When programming a filter for wide-
band it is important to note that the fil-
ter cannot be programmed wider than
the hardware filter being used in the
booster design (typically 1.5 MHz for
the 470-488 range and 3 MHz for the
450-470 range).

When the booster is shipped from the factory it is
programmed in a generic fashion as follows; the
first wideband filter will be set to 500 KHz above
the lowest frequency in the band, the second wide-
band filter will be set to the center frequency of the
band, and the third wideband filter will be set to 500
KHz below the highest frequency in the band. All of
these filters will be set up as 12.5 KHz low delay fil-
ters. Changes to this initial setup are the cus-
tomer’s responsibility. If you need help with
programming your frequencies please contact your
sales representative at Bird Technologies.

Power is applied to the digital booster by plugging
in the AC or DC power cord (depending on how the
system was configured for input power), then turn-
ing the circuit breakers inside the cabinet to the ON
position. The breakers are ganged so they function
as a 2-pole switch, see Figure 6.

NOTE

Figure 6: On/Off Circuit breakers.

Figure 7: Alarm Form-C Contacts.