Page
All Rights Reserved Shyam Telecom Limited
39/43
Next Generation
Signal Enhancement
III) Defective Unit – Replace the unit with a known operational unit. Verify
the signal level at the unobstructed test location. If the signal level
increases, re-verify the weak coverage area. If the weak coverage area
remains marginal, an additional indoor antenna or DB6MR20 may be
required to cover the additional area. If the unit is found to be defective,
please contact our Technical support team. The unit serial number must
be available to establish a return authorization. If replacing any part,
Shyam authorized service dealer should replace it and no soldering/
repairing of PCBs should be carried out in the field for reliable service
thereafter.
IV) Signal Quality Problems
Under certain conditions, the signal level on the mobile handset may
indicate adequate signal strength, but the quality of the signal is
degraded (i.e. distortion).The signal level at the donor antenna is
probably too strong. Under these conditions, the service provider’s
exterior signal level is adequate, in such condition, reduce the forward
path signal using the forward attenuation in the repeater and minimize
the forward signal level in step of 1dB until the problem subsides.
But ensure that the In-Building signal level remains adequate for the
coverage area.
V) Antenna Isolation
Antenna isolation is defined by the path loss or attenuation, between the
donor and server antennas. It is important to ensure that the antennas
are sufficiently separated, such that the signal transmitted by donor
antenna is not received by server antenna and vice versa. For optimal
performance, the separation of the two antennas must provide a path
loss of at least 15 dB greater than the set gain of the repeater.
In most cases, isolation will be achieved by properly locating the donor
and server antennas, respectively. The optimal location for the donor
antenna is high above the roofline, and exterior to the building. The
indoor coverage antenna (server) should be installed inside, near or
below the ceiling. Following guidelines should ensure adequate isolation
between antennas.
a) Never mount the donor or server antenna near a window, where
signals can easily pass through the glass.
b) Mount the donor antenna as high as physically possible to the exterior
of the building, maximizing the vertical separation between the donor
and server antennas. The donor antenna should point towards the
base station site.
c) Install the antennas taking advantage of any existing building structure
such as brick walls, metal roofs, or multiple wall structures to
additionally attenuate the path between them.
d) Whenever using directional antennas inside the building to cover
corridors and hallways, point the indoor antenna away from the donor
antenna location.
e) In extreme cases, the building configuration may not allow for such
separation and isolation. If additional isolation is required, coaxial
