
Rev 1.9.1 Feb.09
Proprietary and Confidential
105
In the event of a discrepancy in values between this guide and the Product Specification Document (PSD), the PSD takes precedence.
Diversity antenna design requirements
(MC57xx / MC8780 / MC8781 / MC8785V /
MC8790 / MC8790V / MC8791V /
MC8792V)
Antenna
diversity
is
required
for
end
user
performance
and
enhanced
coverage
on
CDMA
networks
(800
MHz
/
1900
MHz)
for
MC57xx,
and
on
UMTS
networks
(850
MHz
/
1900
MHz
/
2100
MHz)
for
MC8780
/
MC8781
/
MC8785V
/
MC8790
/
MC8790V
/
MC8791V
/
MC8792V.
(See
on
for
UMTS
diversity
support
by
module.)
In
addition
to
passing
the
specific
tests
described
in
beginning
on
the
diversity
path
antenna
should
satisfy
the
following
requirement:
•
Receive
performance,
measured
by
forward
link
throughput,
must
be
0
to
3
dB
better
than
a
single
antenna
Performance goals
When
designing
the
antenna
system,
consider
the
following
performance
goals:
•
0dB
gain
antenna
(or
better)
•
Diversity
antenna
receive
performance
to
be
similar
to
primary
antenna
•
Separation
distance
or
polarity
separation
to
achieve
diversity
antenna
isolation
of
10db
(minimum)—otherwise
the
receive
antenna
picks
up
too
much
power
radiating
from
the
primary
antenna
GPS antenna design requirements
(MC57xx / MC8775V / MC878x)
A
second
antenna
is
required
to
access
GPS
functionality—if
the
modem
also
supports
diversity,
the
same
antenna
can
be
used.
In
addition
to
passing
the
specific
tests
described
in
beginning
on
the
diversity
path
antenna
should
satisfy
the
following
requirements:
•
Field
of
view
(FOV):
Omni
‐
directional
in
azimuth,
‐
45
°
to
+90
°
in
elevation
•
Polarization
(average
Gv/Gh):
>
0
dB.
Vertical
linear
polar
‐
ization
is
sufficient
(no
need
to
optimize
for
circular
polar
‐
ization)
•
Free
space
average
gain
(Gv+Gh)
over
FOV:
>
‐
6
dBi
(preferably
>
‐
3
dBi).
Note:
Average
gain
is
the
sum
of
average
values
(Gv
+
Gh)
where
both
Gv
and
Gh
are