Low-cost RF over Fiber technology

Transferring high-frequency signals over longer distances using regular coaxial cables will introduce severe cable losses.

An alternative is to use fiber optics which intrinsically has low cable losses. This technology is known as RF-over-Fiber (RFoF) technology or simply optical-coax.

This technology now is available for any application using transport of analog data over coaxial cables but demand for low-losses, safety regulations/galvanic isolation and or a very small space envelope.

As derived from ASTRON's optical transmitter technology for SKA, we've developed an optical link module for low cost, long distance (up to 10 km) signal transport. The module is designed according to the pluggable optics concept: a practical and widely applied approach in the telecommunication industry.

Two of SKA consortia concern the development of mid and low frequency aperture array technology (MFAA, LFAA resp.), both of which are led by ASTRON. Within the latter an optical transmitter and receiver module has been developed for the transfer of signals from the 130000 LFAA antenna to a central processor location.

For realising the lowest cost level, the pluggable optics standards are abandoned. Instead, a package type is developed by ASTRON that is suitable for low cost mechanical fixation in the LFAA system via a clip and by using a low cost USB connector as interface for the RF signal and the electrical power. The optical connection to the laser / photo detector in the module can be realized by applying an optical fiber connector to the module. 

 

Analog signals over low cost fiber interconnects

 

 

The design of the module and its components is such that low cost, mass-production techniques can be applied for its fabrication and assembly. Most of the module can be realized with the use of automated industrial pick-and-place techniques. The remaining (costly) manual labor is minimized via a module design that is optimized for easy assembly.

 

The final development step of the optical link modules is currently being performed in collaboration with Dutch industry. In this collaboration a production flow for the optical link module is being defined, based on the supply chain approach of each involved company. The collaborations are part of an ASTRON activity to prepare the Dutch industry for participating in the construction of the SKA.

 

For more information about our low cost Tx/Rx RfoF modules, please check our brochure.

You may contact our subsidiary AstroTec Holding B.V. for more information regarding pricing information and availability.

Design: Kuenst.    Development: Dripl.    © 2020 ASTRON