External GPS Antenna

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Compact & Sensitive GPS antenna with Excellent Signal Amplification for Mobile Applications

  • High performance
  • Out-band filtering & rejection
  • Fully waterproof
  • Voltage: 2.5 V ~5.5 V DC
  • Provides excellent signal amplification

GA-25 is the integration of a high performance GPS patch antenna and a state-of-the-art low noise amplifier into a very low profile/ extremely compact/ fully waterproof enclosure which, when connected to a GPS receiver with 2.3~5.5V DC antenna power, provides excellent signal amplification and out-band filtering & rejection, provide 3V or 5V input Voltage is available.


  • Compact Construction/ Low Profile/ Fully Waterproof
  • Magnet and Screw Mount Base
  • Excellent Temperature Stability
  • Low Noise Figure
  • High Sensitivity


  • Automobile GPS
  • Bluetooth Receiver
  • Car Tracking Navigation System
  • AVL / Fleet Management Systems
  • External Antenna for Handheld GPS
  • External Antenna for PDA Navigator


Physical Condition
Construction Polycarbonate- radome at top, die-cast shell at bottom/ rubber gasket for water seal in between
Dimension 45.5mm (L) x 34.2mm (W) x 15mm (H)
Weight 80 grams (excluding cable & connector)
Standard Mounting 3M / Magnet mount (Optional)
Optional Mounting Plate customized metal sheet
Environmental Conditions
Operation temperature -40°C to +85°C
Storage temperature -40°C to +100°C
Relative Humidity 95% non-condensing
Cable & Connector
Cable 5 meter RG174/U (standard) cable, other length available
Pulling Strength 6 Kg @ 5sec with molded plastics on connector end for strain relief
Connector Available BNC,TNC,FME (to be adapted), GT5, MCX (OSX), SMA, SMB or SMC in straight or right angle
Optional Adapters Universal Connector Adapter (FME to TNC/BNC/SMA/SMB/MCX)
Antenna Element
Center Frequency 1575.42 MHz +/-1.023MHz
Polarization R.H.C.P. (Right Handed Circular Polarization)
Absolute Gain @ Zenith 3 dBic Typ.
Gain 90 o:2.0dBi min. 20o :-5.0dBi min. Mounted on the 60mm × 60mm square ground plane
Axial Ratio 90o:3 .0dB max. Mounted on the 60mm × 60mm square ground plane
Low Noise Amplifier
Center Frequency 1575.42 MHz +/- 1.023 MHz
Gain 28+/-4.5dB
Bandwidth 10 MHz min. @S11-10 dB
Noise Figure 1.5dB Typ.
Filter 25dB @ fo 50MHz 35dB @ fo 100MHz * fo=1575.42MHz
Supply Voltages 2.5 ~5.5V DC
Current Consumption 2.5V : 6.6mA Typ.
3V: 8.6mA Typ.
4V: 12.6mA Typ.
5V: 16.6mA Typ.
Output Impedance 50 ohm
Output VSWR 2.0 max.
Overall Performance(Antenna Element, LNA & Cable)
Frequency range 1575.42 +/- 1.023 MHz
Gain At 90o 30 ± 4.5dBi-(cable loss) Note:1
Mounted on the 60mm x 60mm square ground plane
Output Impedance 50 ohm
VSWR 2.0 max.

(This specification is subject to change without prior notice)
Note:1:Cable Loss=(-1.2dB/m)

Return loss and Smith Chart for Ceramic Path:

1. Return loss

2. Smith Chart

Insertion Gain and I/O Reflection Coefficient for LNA:
1. LNA Insertion Gain

2. LNA Input reflection Coefficient

3. LNA Output reflection Coefficient

Active Antenna Module:

1. Output VSWR

2. Active antenna Gain

S-parameter Highest Lowest
S21(dB) 11 5

Note: 50 cm measurement S21> 5dB Pass

VSWR ≤ 2


  • Network Analyzer:
    Power: -40Db
  • Power Supply:
    Voltage: 5V Current: 100mA

*AUT: Antenna on 70x70mm metal pillar

IEC/EN 60529 IPX8 contunuous: