UK What a FAKRA connector is
A FAKRA connector is a coaxial connector designed for cars. Inside is an SMB-style 50 ohm RF contact. Around it is a moulded plastic housing with a latch that clicks when the two halves lock, plus a colour and a mechanical key that stop it being plugged into the wrong socket.
The name comes from Fachkreis Automobil, the automotive working group of the German standards body that first specified it. Rosenberger developed the original design, and it is now defined internationally in ISO 20860-1 and -2 and in the US by SAE/USCAR-18. Connector makers including Rosenberger, TE Connectivity, Amphenol and Molex produce interchangeable parts to the standard.
A typical car has a dozen or more FAKRA joints, for GPS, cellular, Wi-Fi, radio and camera links. The same locking, vibration-proof coax connection is why FAKRA has moved into robots, autonomous machines and industrial vision systems.
How FAKRA codes and colours work
FAKRA has 14 codes, each identified by a letter and a housing colour. Each code has its own pattern of ribs and slots, so a plug only mates with a jack of the same code. A car maker assigns a code to each function, for example one for GPS and another for a rear-view camera, and the harness cannot then be cross-connected on the production line.
The exception is code Z, in water blue, which has no key and mates with any FAKRA jack. Z is the code most often found outside cars, including on GMSL cameras and the computers that receive them, because these systems have no need to separate functions. When ordering a FAKRA cable, match the code and colour at each end, the plug or jack gender and whether you need straight or right-angle housings.
In FAKRA, plug and jack name the housings rather than the centre contact. The plug usually sits on the cable end and locks into the jack, which is usually the socket on the camera, antenna or computer. Panel jacks screw or clip into a bracket, and board-mount jacks solder directly to the circuit board.
FAKRA vs Mini FAKRA and other coax connectors
FAKRA is not the only small coax connector on vehicle and edge AI hardware. Its smaller successor, usually called Mini FAKRA or HFM (High-speed FAKRA-Mini, a Rosenberger name), packs up to four coax lines into one housing and reaches higher frequencies.
| Connector | Coupling | Typical frequency | Defined by | Typical use |
|---|---|---|---|---|
| FAKRA | Push-on, latched coded housing | DC to 6 GHz | ISO 20860, USCAR-18 | Vehicle antennas, GMSL cameras |
| Mini FAKRA (HFM) | Push-on, latched, 1 to 4 ways | Up to around 20 GHz | Maker specifications | Multi-camera ADAS and compact boards |
| SMB | Snap-on, no housing | DC to 4 GHz | IEC 61169-10 | Telecom boards, test leads |
| SMA | Threaded nut | DC to 18 GHz | MIL-STD-348 | Antennas and RF equipment |
Mini FAKRA does not mate with standard FAKRA, so check which one a camera and computer use before ordering cables. Adapters exist between FAKRA and SMA for bench testing and antenna work.
Which cable a FAKRA connector uses
FAKRA connectors are crimped onto 50 ohm coaxial cable, and the plug must match the cable diameter. Our explainer on how coaxial cable is built and rated covers the impedance and loss figures behind the choice.
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RG174 and RG316. Thin, flexible 50 ohm cables for short antenna leads. RG316 handles higher temperatures.
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Low-loss automotive coax. Used for GMSL camera links, where the cable must be rated for the link speed and the power carried over the coax.
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Pre-made FAKRA cables. Factory-crimped leads with a fixed code at each end avoid field-crimping errors, which are a common cause of camera dropouts.
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Cable length. Antenna leads are usually short, a few metres at most. GMSL2 camera links typically reach around 15 m, depending on the cable grade, the data rate and how many joints sit in the run.
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Sealed versions. Some FAKRA housings carry a seal for wet locations, but many standard ones are not sealed, so plan the route to keep joints inside an enclosure.
FAKRA in edge AI and industrial vision
Outside cars, FAKRA is mostly found on systems that take several cameras into one computer for real-time perception.
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Robots and autonomous vehicles. GMSL cameras on FAKRA cables feed NVIDIA Jetson computers for navigation, obstacle detection and stereo depth.
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In-vehicle vision. In-vehicle computers with four or eight FAKRA Z inputs run surround view, driver monitoring and road inspection on buses, trains and work vehicles.
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Adding cameras to an existing computer. GMSL frame grabbers put FAKRA inputs on a PCIe card for x86 systems.
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Sensor streaming. Holoscan sensor bridges take GMSL cameras on FAKRA and stream them over Ethernet to a GPU computer.
Quick answers on FAKRA connectors
Our guide to GMSL technology for industrial edge AI explains how the cameras, cables and deserialisers fit together.
FAKRA connectors: common questions
What does FAKRA stand for?
Fachkreis Automobil. It is German for automotive working group, the standards committee that first specified the connector.
Is FAKRA the same as SMB?
Not quite. The RF contact inside a FAKRA connector is SMB-based, but the coded plastic housing and latch make it a different part. A bare SMB plug will not lock into a FAKRA jack.
What is a FAKRA Z connector?
The universal code. Z housings are water blue and have no key, so they mate with any FAKRA code. Most GMSL cameras and camera-input computers use Z.
Is FAKRA 50 or 75 ohm?
50 ohm. Standard FAKRA is a 50 ohm system, so use 50 ohm coax. The housing does not change that, whatever the code or colour.
Can FAKRA connect to SMA?
Yes, through an adapter. FAKRA to SMA adapters and cables are common for connecting a FAKRA antenna to test equipment or an SMA radio. Keep adapters out of GMSL camera links, where each joint adds loss.
We fit GMSL camera inputs, cables and drivers as standard on the edge AI and in-vehicle systems we build, and check every camera channel before the system ships. Send us the camera models, cable runs and mounting positions, and we will specify the FAKRA cables and computer to match.