15
15
Pinout and I/O Description
15
4.2.1.1
ANT_1 Electrical Specifications
Never inject an external DC voltage into the ANT_1 pad as it may damage the module. For
instance, when using a splitter to distribute the antenna signal to several GNSS receivers,
make sure that no more than one output of the splitter passes DC. Use DC-blocks
otherwise.
4.2.2
Auxiliary Antenna
In dual-antenna modules, the auxiliary antenna is connected to the ANT_2 pad. In single-
antenna modules, ANT_2 is not used and must be tied to ground.
Pin Name
Type
Level
Description
Comment
ANT_2
RF
RF input for auxiliary antenna
To be tied to ground in single-antenna
modules
Contrary to the ANT_1 pad, ANT_2 is not ESD-protected and it carries no DC voltage. ESD
protection and biasing must be performed externally. See section 4.2.3.2.
4.2.2.1
ANT_2 Electrical Specifications
1
The pre-amplification gain is the total gain of the distribution network in front of the module. Typically, this
equals antenna active LNA gain minus coax losses in the applicable GNSS bands. The pre-amplification gain
can be computed from the AGC gain reported by the module in the
ReceiverStatus
SBF block and shown
in the web interface or the RxControl GUI. The conversion formula from the reported AGC gain to the pre-
amplification gain is:
Pre-amp gain[dB] = 65 - AGCgain[dB]
So, if the receiver reports an AGC gain of 30dB, the pre-amplification gain is 35dB.
2
The listed noise figure is at room temperature. Add 2 dB for the noise figure at the worst temperature corner
(85°C)
DC bias
DC level provided with the VANT pad
Equivalent DC series impedance at
the ANT_1 pin
2.5 Ohms typical, 3.0 Ohms max
Antenna current limit
150 mA
ANT_1 pre-amplification gain range
1
Single-antenna modules: 15-50 dB (AGC gain: 15-50dB)
Dual-antenna modules: 15-35dB (AGC gain: 30-50dB)
ANT_1 receiver noise figure
2
(NFrx, see Appendix B)
8.5 dB with 15 dB net pre-amplification
18 dB with 25 dB net pre-amplification
26 dB with 35 dB net pre-amplification
35 dB with 45 dB net pre-amplification
RF nominal input impedance
50 Ohms
VSWR
< 2:1 in all the supported frequency bands
DC bias
None, ANT_2 is AC-coupled
ANT_2 pre-amplification gain range
15-35 dB (i.e. AGC gain: 30-50dB)
ANT_2 receiver noise figure
(NFrx, see Appendix B)
6 dB with 15 dB net pre-amplification
14.5 dB with 25 dB net pre-amplification
21 dB with 35 dB net pre-amplification
RF nominal input impedance
50 Ohms
VSWR
< 2:1 in all the supported frequency bands
