As part of its advance toward enabling software defined microwave systems, Teledyne e2v is previewing a prototype optical link technology which might soon make obsolete legacy copper data links in digital radio system design.
"Our optical data link research marks a moment in time when the radio's front-end can finally be decoupled from the advanced backend digital data processing of software defined radios (SDRs). In so doing, designers gain implementation flexibility, enhanced digital beam forming capabilities and several extra design freedoms."
About modern high-speed data interfacing
Two copper-based serial interfaces predominate. They are the industry standard JESD204 link and the alternative, license free ESIstream from Teledyne e2v.
Data interfacing in sampled systems requires considered implementation. Perhaps the largest challenge, particularly in highly parallelized, multi-channel (i.e., electronically steered beam) systems, is ensuring that data samples are accurately time aligned. Time alignment ensures signal phase information and thus, the critical spatial information embedded within the received signals is preserved.
Cross-channel synchronization is further complicated by metastability – an inherent, pseudo-random behavior of digital systems. It can be mitigated through careful design.
Despite optical data links powering the modern global broadband backbone, to date there have been few efforts to replace traditional copper in radio front-end design.
The move to optical data link technology provides multiple system benefits including:
- Lossless, long-range transmission
- Freedom of separation between front-end receive and signal processing systems
- Zero EMI lowers crosstalk and signal interferers
- Weight reduction
The ODH system is at the proof-of-concept stage. Teledyne e2v have extensively simulated the digital design of the control methods and is currently finalizing the first hardware implementation. The company plans several updates throughout this and next year as the project progresses.