Alpha 4ACompact Active Single-Band GPS L1 Adhesive Antenna

The Alpha 4A is a compact, waterproof, self-adhesive GPS antenna designed for reliable L1-band performance. Delivering strong RHCP gain of 27.6 dBiC at zenith, the Alpha 4A also maintains excellent top-hemisphere uniformity with consistent performance across 90° and 120° angular sectors from zenith.

This gain stability ensures dependable satellite visibility and reduced fix times in outdoor environments. The integrated low-noise amplifier (26 ± 2 dB) enhances weak signals, providing a reliable performance for vehicle tracking, fleet management, asset monitoring, and GNSS timing systems.

Supplied as standard with SMA Male connectors and 1 m or 5 m RG174 cable.
Alternative cable lengths and connector types can be specified for high-volume projects.

Key Features

  • Supports GPS L1, Galileo E1, BeiDou B1C, and QZSS L1
  • High RHCP gain up to 27.6 dBiC
  • Consistent coverage across ±90° and ±120° from zenith
  • Low VSWR (1.15 typical) with excellent return loss (−23 dB)
  • Integrated 26 ± 2 dB LNA with ≤ 1.3 dB noise figure
  • Compact IP67 waterproof design with adhesive or optional magnetic mount

Electrical Specifications

  • Frequency Bands: GPS L1 (1575.42 MHz), Galileo E1, BeiDou B1C, QZSS L1
  • Impedance: 50 Ohm
  • Polarisation: RHCP
  • VSWR: <1.5
  • LNA Gain: 26 dB +/-2 dB
  • Noise Figure: <1.3
  • Filter Insertion Loss: <3 dB
  • Supply Voltage: 2.5 – 5 V DC
  • Current Consumption: 10 – 26 mA

Mechanical Specifications

  • Operational Temperature Range: −40 °C to +85 °C
  • Storage Temperature Range: −40 °C to +85 °C
  • Relative Humidity: Up to 95%
  • Ingress Protection: IP67

Mechanical Specifications

  • Dimensions: L38 x W34 x H13 mm
  • Weight: 33 g
  • Cable: RG174
  • Connector: SMA Male
  • Material: ABS
  • Mounting method: Adhesive (Magnetic Mount available for volume orders)

Product Features
A
Adhesive
GNSS
BeiDou
GNSS
Galileo
GNSS
QZSS
GPS
L1
GPS
Position
IP
67
Omni
directional
RHCP
active
lna

Product Compliance
RoHS
Compliant
REACH
Compliant
TSCA
Assessed
CMRT
Aligned
Anti
Slavery

Datasheets

ALPHA 4a IP Test Certificate
Alpha 4A Datasheet

Additional Resources

Antenna Fact Sheet
Understanding Antenna Theory
Antenna 2D Radiation Plot Guide
Visual Guide to Radiation Plots
IP Rating Guide

Ordering Information

Siretta Part Number: ALPHA4A/1M/SMAM/S/S/26
Description: GPS ADHESIVE MOUNT ANTENNA SMA MALE CONNECTOR 1M CABLE

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Siretta Part Number: ALPHA4A/5M/SMAM/S/S/26
Description: GPS ADHESIVE MOUNT ANTENNA SMA MALE CONNECTOR 5M CABLE

Request For Quote

Alternative cable lengths and connector types can be specified for small volume orders