Benjamin J. Puttnam

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We review work on self-homodyne detection (SHD) for optical communication systems. SHD uses a transmitted pilot-tone (PT), originating from the transmitter laser, to exploit phase noise cancellation at a coherent receiver and to enable transmitter linewidth tolerance and potential energy savings. We give an overview of SHD performance, outlining the key(More)
An all-optical regenerator architecture for quadrature phase shift keying format using periodically poled lithium niobate waveguides is presented. As opposed to current fiber-based solutions, the proposed phase-sensitive structure offers small size and good stability while granting similarly efficient operation. Direct quadratic non-linear interactions are(More)
We discuss digital signal processing (DSP) techniques for self-homodyne detection (SHD), multi-core fiber (MCF) transmission links, and related technologies. We focus on exploiting the reduced phase noise of self-homodyne multi-core fiber (SH-MCF) systems to enable DSP resource savings and describe digital receiver architectures that mixes signal and local(More)
We review research progress on new optical devices for SDM networks. Component sharing is expected to be effective for cost reduction, but further improvement of SDM-device performance is needed to realize practical SDM networks.
We report novel results on the improvement in wavelength stability to less than 1-GHz and sub-80ns wavelength tuning times using intelligent wavelength selection in a compact three-section DBR laser module without an active locking mechanism. The performance of the module in terms of switching time and temperature induced wavelength drift is compared to(More)
Space division multiplexing (SDM) is mainly seen as a means to increase data throughput and handle exponential traffic growth in future optical networks. But its role is certainly more diverse. Research on SDM encourages device integration, brings newfunctionality to network elements, and helps optical networks to evolve. As a result, the number of(More)
We review progress on high-capacity multi-core fiber systems based on homogeneous, single mode MCF and focus on the limits of high capacity transmission. We discuss issues of inter-core crosstalk, dynamic inter-core skew and their impact on multi-core fiber systems such as pilot-tone transmission and high-dimensional modulation formats. We summarize(More)
We present and experimentally characterize a spectrally efficient, bidirectional, ultradense wavelength-division multiplexing passive optical network (PON) (2 × 120 Gb/s at 50 GHz) over 30 km standard single-mode fiber. This is achieved using a 4 GHz grid with partial spectrum overlapping, Nyquist-shaped 16-ary quadrature amplitude modulation, and(More)