Clear-Com FreeSpeak Beltpack - Manual (Page 67)

Clear-Com Communication Systems
Eclipse Wireless Communication System 4 - 5
Figure 4-2: Mapping overlapping coverage zones
In some environments you may observe that despite having a high
signal strength, the beltpack consistently reports a high error rate.
This could be due to two things:
• In-band interference from an RF source broadcasting in the DECT
area of the spectrum. This can be verified using a DECT band
monitor (which can be purchased from Vitec Group
Communications), or by using a Spectrum Analyser.
• Long Delay Spread Multipath, where the signal is bounced off a
number of reflective surfaces, such as metal ceilings, gantries,
walkways or other large structures. This problem is greatest
where the reflective surface is large and exists at a range of
distances from the antenna. To resolve this problem, consider
siting the antenna where it cannot “see” the reflective surface,
installing a reflector close to the antenna between it and the
reflective surface, or purchasing directional antennas. Contact
VGC customer support for more information.
TESTING ANTENNA HANDOFF
After you test the coverage areas for individual antennas, test the
handoff between the antennas. When you walk through a coverage
area with the beltpack, the beltpack searches to find the antenna with
the best signal strength, and switches transmission to that antenna.
Therefore the beltpack continually hands off transmission among
antennas as you move through the coverage area.
To test antenna handoff, connect any additional antennas in the
installation and walk through the coverage areas to ensure that the
coverage is continuous and complete, without audio breakups. You
can tell which antenna the beltpack transmits to by looking at the RPN
number in the top rightmost corner of the beltpack’s display when the
beltpack is in “site survey” mode. Reposition antennas if necessary.
Note that the numbering to identify antennas starts at “6” to identify the
first antenna, as shown in the table below.
Zone A
Zone B
Zone C
1 User
5 Users
4 Users