u-blox ZED-F9T - Antenna Bias

ZED-F9T-Integration Manual
Figure 31: u-blox low cost dual-band antenna internal structure
A suitable ground plane is required for the antenna to achieve good performance.
Location of the antenna is critical to reach the stated performance.
L1 + L2/E5b active antenna required specifications
Parameter Specification
Antenna Type Active antenna
Typical gain 30 dB
Maximum gain 40 dBActive antenna recommendations
Maximum noise figure 2 dB
L1 band antenna gain
1
1559 - 1606 MHz: 3 dBic typ.
L2/E5b band antenna gain
2
1197 - 1249 MHz: 2 dBic typ.
Polarization RHCP
Axial ratio 2 dB max at Zenith
Phase center variation <10 mm over elevation/azimuth
Group delay variation in-band
3
10 ns max @ each GNSS system bandwidth. Note:
Inter-signal requirement 50 ns max.
EMI immunity out-of-band
4
30 V/m
Out-of-band
5
Rejection
40 dB typ
ESD circuit protection 15 kV human body model air discharge
Table 23: Antenna specifications for ZED-F9T modules
The antenna system should include filtering to ensure adequate protection from nearby
transmitters. Care should be taken in the selection of antennas placed close to cellular or Wi-Fi
transmitting antennas.
4.4.1 Antenna bias
Active antennas have an integrated low-noise amplifier that contributes an additional current of
typically 5 to 20 mA to the system's power consumption budget. If customers do not want to make
use of the antenna supervisor function the filtered VCC_RF supply voltage output can supply the
1
Measured with a ground plane d=150 mm
2
Measured with a ground plane d=150 mm
3
GNSS system bandwidths: 1559… 1563 MHz; 1573… 1578 MHz; 1598… 1606 MHz; 1192… 1212 MHz; 1197…
1217 MHz; 1223… 1231 MHz; 1242… 1249 MHz
4
Exception L1 and L2 bands +/- 200 MHz, emphasis on cellular bands
5
GNSS system bandwidths: 1559… 1563 MHz; 1573… 1578 MHz; 1598… 1606 MHz; 1192… 1212 MHz; 1197…
1217 MHz; 1223… 1231 MHz; 1242… 1249 MHz
UBX-19005590 - R01
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