THE CHALLENGEA Good Tracker Lives or Dies on Its RF
Two trackers with the same modem and the same GNSS module can perform completely differently in the field, and the difference is almost always the antenna and RF layout. A poorly matched antenna, a starved ground plane, or a cellular transmitter desensitizing the GNSS receiver will produce dropped fixes and weak signal that no firmware can fix. The RF has to work inside the real plastic enclosure, near the battery and the human body, not on an open bench. Antenna placement, matching, and coexistence are treated as design problems to solve up front, then proven with radiated measurement.
Sits inside the GPS tracking device engineering stack and shares hardware and platform building blocks with GNSS Module Integration.
WHEN YOU NEED THIS
When RF Performance Is on the Line
You need dedicated RF and antenna work when a compact tracker has to hold a fix and a cellular link in a small, sealed enclosure, or when an existing design underperforms in the field and the cause is not obvious from the firmware.
Compact and Sealed Devices
Personal trackers, asset tags, and wearables where the antenna shares a tiny board with the battery and there is no room for a clean ground plane or keep-out.
NavIC and Multi-Band GNSS
Devices that must receive NavIC on L5 and S-band alongside GPS L1, where the antenna has to cover bands a single chip ceramic patch was never tuned for.
Underperforming Existing Designs
Products already in production with dropped fixes, weak signal, or GNSS that dies whenever the modem transmits. Scope covers diagnosing the matching, layout, and coexistence problem.
SCOPE OF WORK
What's Included
GNSS Antenna Selection
A passive ceramic patch or an active antenna with a built-in LNA is selected based on the cable run, board size, and noise environment. For active designs, LNA gain and the supply path are set to lift the satellite signal before the trace loss and noise of the rest of the board degrade it.
Cellular Antenna Matching
The pi matching network for the cellular antenna is tuned with a vector network analyzer against the actual board and enclosure rather than the datasheet. The match holds across the bands the modem uses so registration and uplink stay reliable at the cell edge.
Ground Plane and Keep-Outs
Ground plane geometry, antenna keep-out zones, and component placement are defined so the antenna sees the reference it needs. On a small board this often drives the whole PCB stackup and floorplan, so it is settled before the layout is locked.
NavIC L5 and S-Band Coverage
For NavIC and IRNSS, antennas that cover L5 and S-band alongside GPS L1 are selected and tuned, with RF routed so the multi-band receiver gets a clean signal across every constellation the device is certified against.
TECHNICAL APPROACH
How the RF Is Made to Work
RF problems are cheap to fix on paper and expensive to fix after tooling, so antenna and layout decisions are front-loaded and validated with measurement at each stage rather than left to chance once assembled.
Layout First
The antenna is placed, the ground plane defined, and the 50 ohm RF traces routed with controlled impedance before the rest of the board is committed. The cellular transmit path is kept away from the GNSS receive path from the start.
Coexistence
The cellular transmitter can desensitize the GNSS receiver, so harmonics are managed, filtering is added where a transmit band falls near the GNSS band, and the two antennas are physically separated to keep the receiver listening while the modem talks.
Measure and Tune
Matching networks are tuned on real hardware with a VNA, then verified in the assembled enclosure because the plastic and battery shift the tuning. Time-to-first-fix and signal quality are confirmed in the field, not just on the bench.
INTEGRATION AND OUTPUTS
What You Get Back
The RF work lands as a layout you can build, tuned matching component values, and pre-compliance measurement data that de-risks the formal radiated test later.
Build-Ready RF Layout
Antenna placement, ground plane, matching network values, and controlled-impedance routing are delivered as part of the PCB so the design goes to fabrication with the RF already solved.
Pre-Compliance Test Data
Radiated pre-compliance measurements characterize spurious emissions and antenna performance before you book the certification lab, cutting the risk of a failed formal test and a respin.
FAQ
Common Questions
Passive or active GNSS antenna, which one fits?
It comes down to the signal path. A passive ceramic patch works well when the antenna sits close to the receiver with a short, low-loss trace and a solid ground plane. An active antenna adds an LNA to recover signal lost to a long cable or a noisy board, at the cost of supply current and a bias path. The choice is driven by your board size, cable run, and power budget.
Why does GPS drop out when the cellular modem transmits?
That is a coexistence problem. The cellular transmitter radiates strong energy that can desensitize the sensitive GNSS receiver listening for very weak satellite signals nearby. The fix is antenna separation, filtering where transmit harmonics fall near the GNSS band, and careful layout so the receive path stays clean while the modem is active.
Can one antenna design cover NavIC as well as GPS?
NavIC uses L5 and S-band, which a typical GPS L1 patch does not cover, so the design uses multi-band antennas tuned for the constellations the device must support, with an RF front end built to receive them together. This matters for AIS 140 and NavIC compliance where the device has to demonstrate NavIC reception.
Need Your Tracker to Hold a Fix?
Share your enclosure, band requirements, and where the current design falls short to get an antenna and RF front end designed and proven with measurement.
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