GPS Antenna Types
Edit on GitHubThe GPS antenna types used on the NEO-6M modules: ceramic patch, active versus passive, and the field differences.
GPS Antenna Types
The little square on the GPS module is an antenna: a ceramic patch. Its type and its active/passive state decide how well the module sees the sky.
The ceramic patch
The standard NEO-6M module carries a 25 x 25 mm or 15 x 15 mm ceramic patch antenna. It is a directional antenna: it wants to face up, with its best reception directly overhead. The GPS Sky View page explains why orientation matters.
Active versus passive
| Type | Amplifier | Needs | Use |
|---|---|---|---|
| Passive | None | A strong signal path | Short cable, clear sky |
| Active | Built-in LNA | 3 V supply through the coax | Long cable, indoors, marginal conditions |
Most NEO-6M boards are passive. “Active” modules (with an SMA connector and a powered antenna) exist for GPS-denied situations and car use; the beacon’s standard build does not need one.
The field differences
| Situation | Passive patch | Active antenna |
|---|---|---|
| Open sky | Excellent | Excellent |
| Dense canopy | Weak | Better |
| Inside a backpack | Useless | Marginal |
| Power draw | 0 extra | +5 - 15 mA |
The beacon’s GPS is passive by design: lower power, no extra supply path, and the mission puts the antenna on the case top in open air (see GPS Antenna Placement).
The ground plane question
A patch antenna does not need the metal ground plane a whip needs (see Quarter Wave Antenna): the patch is self-contained. What hurts it is nearby metal and dielectric (the battery, the board, a metal case top).
Related pages
- GPS Antenna Placement for the mounting
- GPS Sky View for the view
- GPS Module Variants for the module choice