Fronthaul evolution: From CPRI to Ethernet

It is proposed that using Ethernet in the fronthaul, between base station baseband unit (BBU) pools and remote radio heads (RRHs), can bring a number of advantages, from use of lower-cost equipment, shared use of infrastructure with fixed access networks, to obtaining statistical multiplexing and optimised performance through probe-based monitoring and software-defined networking. However, a number of challenges exist: ultra-high-bit-rate requirements from the transport of increased bandwidth radio streams for multiple antennas in future mobile networks, and low latency and jitter to meet delay requirements and the demands of joint processing. A new fronthaul functional division is proposed which can alleviate the most demanding bit-rate requirements by transport of baseband signals instead of sampled radio waveforms, and enable statistical multiplexing gains. Delay and synchronisation issues remain to be solved

High-Speed Train Cell-less Network Enabled by XGS-PON and Impacts on vRAN Split Interface Transmission

We successfully demonstrate a transmission of a high layer split mobile interface for cell-less, high-speed train network applications using a commercially available XGS-PON. Operation is also demonstrated for a GbE interface

Efficient T-CONT-agnostic Bandwidth and Wavelength Allocation for NG-PON2

Dynamic bandwidth and wavelength allocation are used to demonstrate high quality of service (QoS) in time wavelength-division multiplexed–passive optical networks (TWDM-PONs). Both bandwidth and wavelength assignment are performed on the basis of transmission containers (T-CONTs) and therefore by means of upstream service priority traffic flows. Our medium access control (MAC) protocol therefore ensures consistency in processing alike classes of service across all optical network units (ONUs) in agreement with their QoS figures. For evaluation of the MAC protocol performance, a simulator has been implemented in OPNET featuring a 40 km, 40 Gbps TWDM-PON with four stacked wavelengths at 10 Gbps each and 256 ONUs. Simulation results have confirmed the efficiency of allocating bandwidth to each wavelength and the significant increase of network traffic flow due to adaptive polling from 9.04 to 9.74 Gbps. The benefit of T-CONT-centric allocation has also been measured with respect to packet delay and queue occupancy, achieving low packet delay across all T-CONTs. Therefore, improved NG-PON2 performance and greater efficiency are obtained in this first demonstration of T-CONTs allocated to both wavelength and time.Peer reviewe

Bidirectional 2.5-Gb/s WDM-PON Using FP-LDs Wavelength-Locked by a Multiple-Wavelength Seeding Source Based on a Mode-Locked Laser

Topic "Networks and Systems"International audienceWe experimentally investigate the operation of a cost-effective wavelength-division-multiplexed passive optical network (WDM-PON) based on wavelength-locked Fabry-Pérot laser diodes (FP-LDs). A single quantum-dash passively mode-locked laser (QD-MLL) is combined with an arrayed waveguide grating in WDM-PON architecture to provide a low-noise, coherent multiwavelength seeding source to injection-lock the FP-LDs for both downstream and upstream. The results show that the QD-MLL-injected FP-LD has the same performance when compared to the case of injection-locking by a low-noise external cavity laser. Error-free bidirectional transmission over 25 km for 16 channels with 42.7-GHz channel spacing is demonstrated at 2.5 Gb/s in the C-band and an optical budget higher than 30 dB is reached

Subsystems for future access networks

Current evolution and tendencies of Telecom Networks in general and more specifically optical Metro and Access Networks and their convergence are reported. Based on this evolution, a set of research lines are foreseen regarding subsystems and devices as: high speed optical sources, modulators and receivers, for the next generation of Passive Optical Networks. The ICT project EURO-FOS is achieving European level cooperative research among academia and industry, enabling future telecommunication networks

Interoperability of GPON and WiMAX for network capacity enhancement and resilience

This paper was published in Journal of Optical Networking and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/JON/Issue.cfm. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law. Copyright Optical Society of America.The interoperability of standard WiMAX and GPON is shown to overcome the wireless spectrum congestion and provide resilience for GPON through the use of overlapping radio cells. The application of centralised control in the optical line terminal (OLT) and time division multiplexing for upstream transmission enables efficient dynamic bandwidth allocation for wireless users on a single wavelength as well as minimised optical beat interference at the optical receiver. The viability of bidirectional transmission of multiple un-coded IEEE802.16d channels by means of a single radio frequency (RF) subcarrier at transmission rates of 50 Mbits/s and 15 Mbits/s downstream and upstream respectively for distances of up to 21 km of integrated GPON and WiMAX micro-cell links is demonstrated.Peer reviewe

Colorless Components for WDM-based Optical Access Networks

Section B "PHOTONICS & LASERS AND APPLICATIONS" [B-45]International audienceThis paper presents our work carried out in the colorless-component technologies for high bit-rate optical access networks, which are based on WDM-PON (wavelength division multiplexed passive optical networks). The colorless concept consists in using identical and wavelength-independent components that will act as the generic transmitter in WDM-PON systems. The transmitted wavelength is imposed, for each colorless component, by an external optical signal. Our studies include two types of colorless components: The Injection-Locked Fabry-Perot laser (IL-FP) and the Reflective Electro-Absorption Modulator integrated with a Semiconductor Optical Amplifier (REAM-SOA). For the IL-FP, the properties of the component strongly depend on the injected optical signal. We demonstrate the improvement by injection-locking of the laser's performances in terms of intensity noise, chirp and bandwidth. For the REAM-SOA, the static properties such as reflection gain and noise characteristic are examined. We demonstrate the feasibility of the REAM-SOA in a transmission experiment in a PON configuration at 10 Gbps with up to 25 km of SMF, using remote modulation technique

System aspects of the FDMA PON conceived within the FABULOUS European project (Invited)

International audienc