Rf Interference; Synchronous Ethernet And Synchronous Ethernet Generation; Figure 10 Maximum Gps Receiver Interference Power Level Vs. Frequency - Nokia Flexi Zone Pico Product Description

Flexi Zone Indoor Pico BTS Product Description

7.1.2 RF Interference

7.2 Synchronous Ethernet and Synchronous Ethernet
Issue: 01
DC Block: All output ports must supply a DC Block to protect the FZP GPS inputs.
•
GPS Networking Inc. is one of the vendors that provide this type of equipment which can
meet these requirements. Below are some example part numbers:
8-Port: AL-DCB-S1X8-N/5/110
•
16-port Rack mount: RMAL-DCB-S1X16-N/5/110
•
32-port Rack mount: RMAL-DCB-S1X32-N/5/110
•
These models include the DC Block on all output ports, provide the 5 VDC for the active
antenna, utilize N type connections and are powered via 110 VAC. For other AC power
options the "110" in the part number above can be replaced with either "220" or "240"
depending on the available local power. If utilizing a distribution network insure that all
grounding and surge suppression requirements are followed.
While the BTS GPS receiver and recommended antennas provide a high level of out of
band interference, rejection care needs to be taken to avoid placing the GPS antenna in
the direct radiation path of cellular or other transmit antennas. To minimize interference
potential the GPS antenna needs to be positioned at a different elevation and as far as
possible from nearby transmit antennas. The graph presented in Figure 10: Maximum
GPS Receiver Interference Power Level vs. Frequency can be used to identify the
maximum interference source power levels presented at the GPS antenna surface
(assuming that a Nokia recommended GPS antenna is in use and RF signal presented
to the GPS receiver meets all level and noise figure requirements).
Different interference rejection performance can be experienced with other (non-Nokia
recommended) GPS antenna types or when the GPS receiver is not provided with the
required (minimum or maximum) RF signal levels.
Figure 10 Maximum GPS Receiver Interference Power Level vs. Frequency
Power
Level
-5dBm
-45dBm
-110dBm
generation
According to G.8261, Synchronous Ethernet provides a SDH-like mechanism for
distributing frequency information at Layer 1. The BTS receives the frequency
information from the directly connected (next-hop) Ethernet switch or IP router through
the Ethernet link.
Interferenceabovelimits
Interferencewithinlimits
DN09210454
Synchronization
Frequency
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