An overall summary of the 5G-PHOS progress and main achievements is provided below:
High speed photodiodes were developed and integrated, while an implementation of on chip biasing circuit with a 50Ω matching resistor could allow for >110 GHz bandwidth on 25Ω effective load. A mini-ROADM was developed and fully characterized, achieving ultra low-losses of 2.55 dB. Fully packaged Rx & Tx OBFN prototypes were developed, hosting all the required driving electronics and GUI. The project has also completed and characterized the development of the Flexbox and RRH prototypes that are a crucial part of the 5G-PHOS architecture. This included the development of the complete Transmitter-Receiver DSP chain, supporting OFDM waveforms with up to 1.6Gb/s user data-rate, when modulating and transmitting a 16-QAM modulation format and 400 MHz bandwidth. Regarding resource allocation, the consortium has performed an analytical study regarding the optimal utilization of radio and optical resources in converged FiWi X-haul transport network for 5G communications. The consortium also studied the problem of concurrency between of real-time and non real-time traffic over the 5G-PHOS solution and introduced Quality-of-Service characteristics considering two traffic categories, i.e. Express and Best Effort traffic, while devising 3 traffic prioritization schemes, such as Simple Priority, Priority with Packet Pre-emption and Dedicated Sub-band allocation. With respect to SDN functionalities, the consortium has delivered the final version of the 5G-PHOS SDN controller, termed as the NPO tool. The NPO tool has also been tested and debugged within the scope of Demonstrators #2 and #3 of the project. Regarding demonstrators the 5G-PHOS technologies were evaluated in lab-environments of Fiber Wireless links, demonstrating its capability to deliver 1 Gb/s user data rate, 120 degrees beamsteering, multi-user network scenarios and up to 10 Gb/s peak data traffic for the RRH technologies, and regarding the FlexBox, real-time Ethernet-to ARoF transmission over the field-deployed PON of TIM and bidirectional transmission using OFDM waveform with up to 1.6 Gb/s data-rate. Moreover, two Demonstrators were completed successfully, with Demo #3 concluding to three successful real-time services UHD video transmission, iperf measurements with 237 Mb/s data-rate and SDN controlled wavelength allocation through proper VLAN-tags over a 6m radio distance that can potentially scale up to 117m based on the experimental dynamic range, while Demonstrator #2 has also exhibited a variety of services running real-time over the 5G-PHOS solution, with the SDN controller automatically and dynamically controlling the number of bands allocated at the system.
Finally, the 5G-PHOS project’s scientific findings have been published in prestigious international journals, conferences, and workshops, with the project reaching a total of 125 publications throughout its lifetime.