Product overview
The vehicle shark-fin antenna puts several RF elements inside one roof housing. A typical build combines cellular, GNSS, broadcast, or private-network feeds, so an OEM or aftermarket vehicle can carry more than one service through a limited set of holes.
The table is the electrical and mechanical outline for this order code. Body sheet metal and glass coating change the efficiency you measure. Cable routes and the earth bond have to follow the vehicle harness practice. The hardware specification governs.
Reliability on the roof
Washes, ice, snow, and salt spray test the seal and the connectors. Use automotive cable, and do not put a right-angle bend in the feeder or the VSWR will rise.
When several antennas share the roof, watch transmit-receive isolation and intermodulation. After the fit, run a full-band VSWR and sensitivity road test, and keep a retest record after a water spray and a vibration run.
Key specifications
RF and mechanical figures below are a typical build, for selection and for a tender clause. To add or drop a band, change the MIMO count, or take an automaker approval file, ask SimtoLink for the hardware specification and the installation and commissioning guide. Order codes in the family can differ. The nameplate and the papers shipped with the antenna govern.
| Parameter | Specification | Notes |
|---|---|---|
| Bands | Cellular / GNSS / Wi‑Fi and more | Follows the order BOM |
| Gain | Cellular about 2～6 dBi | Measured on the vehicle |
| VSWR | <2.5 | Typical cellular port |
| Polarization | Cellular ±45° / linear and others | Matches the module MIMO definition |
| Impedance | 50 Ω | Independent feeder per port |
| Power | Limited by the module and the rules | Count each port on its own |
| Ingress | IP54～IP67 | Automotive seal follows the specification |
| Feeder | Automotive low-loss coax set | Route and bend radius are limited |
| Operating temperature | -40～85 ℃ | Typical automotive range |
| Mounting | Roof hole + seal | Body earth bond |
Typical applications
Four fits that come up often, for the design and for a payback check:
Ride-hailing and taxis
Multi-mode positioning and 4G/5G backhaul in one fin, with fewer holes in the roof.
Logistics and cold-chain trucks
Positioning and the in-vehicle gateway antenna share the roof, which helps remote temperature control and a track audit.
Police and emergency vehicles
Private-network and public-network antennas share one housing, so drag and EMC stay in balance.
Buses and coaches
Passenger-count, video, and dispatch links share one managed antenna set.
Installation, grounding, and maintenance
- Cut the roof to the body template. Seat the sealant and the clips in one pass so water cannot short the feed.
- Run the feeder in the original channel, away from ignition and high-current motor loops.
- Roof earth and body bond resistance have to meet the automaker or the conversion rule.
- Check color rings and RF labels on a multi-port antenna so a swapped lead does not raise a VSWR alarm.
- After a crash or a body repair, measure VSWR and GNSS C/N₀ on every port again.
Ordering, documentation, and support
The hardware specification, an outline drawing, the wiring table, and a sample project are available from SimtoLink. A volume order can include a sample review and an inspector at the plant. Warranty and calibration follow the contract and the papers packed with the antenna.