RF boards go open source

Lime Microsystems has decided to join the open-source hardware movement in the hope of building an RF analog of the Arduino and, in the process create a wider user base for its RF transceiver devices.

Several years ago, the company started work on a transceiver will work with most wireless protocols in the 300MHz to 3.8GHz range, including cellular and unlicensed spectrum.

“We began an effort to supply our evaluation kits to practically anyone who came to us. We’ve built a customer base of over 150 people,” said Ebrahim Busherhi, Lime CEO. “There are about half a dozen that are now in production. There is quite a long tail of people who are doing some really interesting stuff. We saw a lot of potential for innovation, especially among people developing software stacks for things like LTE and GSM.

“What was missing was something that gave them easy access to engage with the RF side,” said Busherhi. “It is quite advantageous to your complete system running from the outset rather than having the ability to transmit wirelessly as an afterthought.”

Conventional designs of this kind often work with an off-the-shelf transceiver that then needs to be replaced with the production model. “You really need to modify the code when it is in place,” said Busherhi. Having something that more closely resembles the finished system during development and which can be modified for production can avoid that issue.

The Myriad-RF board as it stands today does not fit into the Arduino ecosystem as the open-source hardware is trying to cover a wider range of host systems.

“We have integrated ADCs and DACs that conform to the parallel IQ multiplex data format. We wanted to keep it general as a lot of people are doing development work alongside FPGA designers,” Busherhi explained.

The board designs from the Myriad website are offered under a Gnu Public Licence. Designs can be downloaded in the form of a KiCAD file so that they can be modified using an open-source design tool.