Johannes von Hoyningen-Huene

Constant envelope optical OFDM for improved nonlinear and phase noise tolerance

We introduce a new concept of OFDM transmission with constant envelope and coherent detection to reduce the sensitivity of OFDM signals to nonlinear effects and phase noise.

37.5 km urban field trial of OFDMA-PON using colorless ONUs with dynamic bandwidth allocation and TCM [invited]

The orthogonal frequency division multiple access (OFDMA)-based passive optical network (PON) is a potential candidate to meet the flexibility requirements for next-generation optical access networks. We propose an OFDMA-based PON with a transmission employing intensity modulation/direct detection in the downstream and a remodulation of a remotely seeded carrier provided by the optical line terminal with coherent detection in the upstream, which enables cost-effective colorless optical network units (ONUs). Furthermore, an OFDMA-PON field trial using the proposed scheme over 37.5 km feeder fiber is demonstrated. A power budget supporting 32 ONUs with dynamic bandwidth allocation and trellis coded modulation (TCM) is reported.

Timing Advance Tracking for Coherent OFDMA-PON Upstream System

A synchronization algorithm for coherent OFDMA-PON upstream is proposed. The feasibility of the tracking functionality is experimentally investigated. A differential delay of up to 37.6 ns was tracked and could be compensated at the ONU.

Asynchronous Signal Reception in OFDMA-PON-Uplink

We propose an OFDMA-PON receiver DSP structure that is tolerant to timing offsets of the multiplexed upstream signals. With this technique complex synchronization requirements of the PON can be avoided.

Experimental IM/DD OFDMA transmission with scalable receiver frontend for PON scenarios

We propose a technique to reduce the electrical hardware effort in an OFDMA-PON by reducing the ADC and DSP complexity and therefore the costs of the ONUs and show its feasibility experimentally.

Nonlinearity compensation and equalization in access networks

In this paper we give an overview over the nonlinear impairments arising in passive optical networks (PON) and show different approaches to compensate for them before and after the transmission.

OFDM remodulation for 10-Gb/s/channel WDM-PON with simple carrier extraction and enhanced tolerance to Rayleigh noise

A novel OFDM-remodulation scheme for 10-Gb/s/channel WDM-PON is proposed and numerically investigated. Negative remodulation penalty is achieved without using any ultra-narrow filter or coherent detection. 40-km single-fiber bidirectional transmission is confirmed with 7-dB power margin.

Passive optical networks based on OFDM: Perspectives and experimental verifications

Investigate the different requirements for OFDMA-PON in downstream and upstream direction. We show an approach to reduce the DSP effort at the ONUs and demonstrate the OFDMA upstream transmission with four individually modulated ONUs with central distribution of the optical carrier and coherent reception at the OLT.

Field trial of an OFDMA-PON system

OFDM is an interesting candidate to meet the requirements of high flexibility and speed for the next generation optical access networks. We show an OFDM system utilizing a timing advance tracking algorithm to realize a synchronized upstream transmission. Therefore, a dynamic bandwidth allocation can be used in the upstream and an interleaved assignment is made possible. We then demonstrate the feasibility in a field trial with four individual ONUs using a 37.5 km field deployed feeder fiber of the Deutsche Telekom AG. Power loading and the trellis coded modulation was used to achieve a power budget supporting 32 ONUs for up- as well as downstream transmission.