User's Manual

11
RA
K20
11
RAK7248
11
Conditions Temperature Humidity
Working -35 ºC ~ +80 ºC 0% ~ 95%
Storage -40 ºC ~ +85 ºC 0% ~ 95%
Table 7| GPS Environmental Requirements
3.2.4GPS Antenna Parameter
Antenna specifications are listed in the table below:
Item Specifications PET
Range of Receiving Frequency 1575.42±1.1 ±2.5
Center Frequency (MHz) w/ 30mm2 GND plane 1575.42 ±3.0
Bandwidth (MHz) (Return Loss -10dB) ≥10 ±0.5
VSWR (in Center Frequency) ≤2.0 ±0.5
Gain (Zenith) (dBi Typ.) w/ 70mm2 GND Plane 4.5 ±0.5
Axial Ratio (dB) w/ 70mm2 GND Plane 3.0 ±0.2
Polarization Right-Handed Circular -
Impedance (Ω) 50 -
Frequency Temperature Coefficient (ppm/ºC) 0±10 -
Table 8| GPS Antenna Paramete
Amplifier Specifications are listed in the table below:
Item Specifications
Frequency Range 1575.42 MHz
Gain 27 dB
VSWR ≤ 2.0 V
Noise Coefficient ≤ 2.0 dBm
DC Voltage 3 ~ 5 V
DC Current 5 ± 2 mA
Table 9| Amplifier Specifications
Environmental test performance specifications are listed below:
Item Normal Temp. High Temp.
1
Low Temp.
2
Amplifier Gain 27dB ± 2.0 27dB ± 2.0 27dB ± 2.0
VSWR ≤ 2.0 ≤ 2.0 ≤ 2.0
Noise Coefficient ≤ 2.0 ≤ 2.0 ≤ 2.0
1. High temperature test: soap in temperature (85º C) and humidity (95%) chamber for 24-
hour and return to normal temperature (at least for 1-hour) without visual shapechange.