TOBY-L2 and MPCI-L2 series - System Integration Manual
UBX-13004618 - R07
Advance Information
System description
Page 36 of 158
1.7.1.1
Antenna RF interfaces requirements
Table 8, Table 9 and Table 10 summarize the requirements for the antennas RF interfaces (
ANT1
/
ANT2
). See
section 2.4.1 for suggestions to properly design antennas circuits compliant with these requirements.
The antenna circuits affect the RF compliance of the device integrating TOBY-L2 and MPCI-L2
series modules with applicable required certification schemes (for more details see section 4).
Compliance is guaranteed if the antenna RF interfaces (ANT1 / ANT2) requirements summarized
in Table 8, Table 9 and Table 10 are fulfilled.
Item
Requirements
Remarks
Impedance
50
nominal characteristic impedance
The impedance of the antenna RF connection must
match the 50
impedance of the
ANT1
port.
Frequency Range
See the
TOBY-L2 series Data Sheet
[1] and the
MPCI-L2 series Data Sheet
The required frequency range of the antenna connected
to
ANT1
port depends on the operating bands of the
used cellular module and the used mobile network.
Return Loss
S
11
< -10 dB (VSWR < 2:1) recommended
S
11
< -6 dB (VSWR < 3:1) acceptable
The Return loss or the S
11
, as the VSWR, refers to the
amount of reflected power, measuring how well the
primary antenna RF connection matches the 50
characteristic impedance of the
ANT1
port.
The impedance of the antenna termination must match
as much as possible the 50
nominal impedance of the
ANT1
port over the operating frequency range, reducing
as much as possible the amount of reflected power.
Efficiency
> -1.5 dB ( > 70% ) recommended
> -3.0 dB ( > 50% ) acceptable
The radiation efficiency is the ratio of the radiated power
to the power delivered to antenna input: the efficiency is
a measure of how well an antenna receives or transmits.
The radiation efficiency of the antenna connected to the
ANT1
port needs to be enough high over the operating
frequency range to comply with the Over-The-Air (OTA)
radiated performance requirements, as Total Radiated
Power (TRP) and the Total Isotropic Sensitivity (TIS),
specified by applicable related certification schemes.
Maximum Gain
According to radiation exposure limits
The power gain of an antenna is the radiation efficiency
multiplied by the directivity: the gain describes how
much power is transmitted in the direction of peak
radiation to that of an isotropic source.
The maximum gain of the antenna connected to
ANT1
port must not exceed the herein stated value to comply
with regulatory agencies radiation exposure limits.
For additional info see the section 4.2.2.
Input Power
> 33 dBm ( > 2 W )
The antenna connected to the
ANT1
port must support
with adequate margin the maximum power transmitted
by the modules.
Table 8: Summary of primary Tx/Rx antenna RF interface (ANT1) requirements
