Next Issue
Previous Issue

Table of Contents

Photonics, Volume 1, Issue 2 (June 2014), Pages 67-161

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
View options order results:
result details:
Displaying articles 1-7
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle Optical Systems for Ultra-High-Speed TDM Networking
Photonics 2014, 1(2), 83-94; doi:10.3390/photonics1020083
Received: 13 February 2014 / Revised: 10 April 2014 / Accepted: 11 April 2014 / Published: 25 April 2014
PDF Full-text (590 KB) | HTML Full-text | XML Full-text
Abstract
This paper discusses key results in the field of high speed optical networking with particular focus on packet-based systems. Schemes for optical packet labeling, packet switching and packet synchronization will be discussed, along with schemes for optical clock recovery, channel identification and [...] Read more.
This paper discusses key results in the field of high speed optical networking with particular focus on packet-based systems. Schemes for optical packet labeling, packet switching and packet synchronization will be discussed, along with schemes for optical clock recovery, channel identification and detection of ultra-high-speed optical signals. Full article
(This article belongs to the Special Issue All Optical Networks for Communications)
Figures

Open AccessArticle Comparison of Regularization Methods in Fluorescence Molecular Tomography
Photonics 2014, 1(2), 95-109; doi:10.3390/photonics1020095
Received: 1 February 2014 / Revised: 14 April 2014 / Accepted: 17 April 2014 / Published: 29 April 2014
Cited by 4 | PDF Full-text (3755 KB) | HTML Full-text | XML Full-text
Abstract
In vivo fluorescence molecular tomography (FMT) has been a popular functional imaging modality in research labs in the past two decades. One of the major difficulties of FMT lies in the ill-posed and ill-conditioned nature of the inverse problem in reconstructing the [...] Read more.
In vivo fluorescence molecular tomography (FMT) has been a popular functional imaging modality in research labs in the past two decades. One of the major difficulties of FMT lies in the ill-posed and ill-conditioned nature of the inverse problem in reconstructing the distribution of fluorophores inside objects. The popular regularization methods based on L2, L1 and total variation (TV ) norms have been applied in FMT reconstructions. The non-convex Lq(0 < q < 1) semi-norm and Log function have also been studied recently. In this paper, we adopt a uniform optimization transfer framework for these regularization methods in FMT and compare their individual, as well as the combined effects on both small, localized targets, such as tumors in the early stage, and large targets, such as liver. Numerical simulation studies and phantom experiments have been carried out, and we found that Lq with q near 1/2 performs the best in reconstructing small targets, while joint L2 and Log performs the best for large targets. Full article
(This article belongs to the Special Issue Biomedical Optics and Optical Imaging)
Open AccessArticle Optical Backplane Based on Ring-Resonators: Scalability and Performance Analysis for 10 Gb/s OOK-NRZ
Photonics 2014, 1(2), 131-145; doi:10.3390/photonics1020131
Received: 25 March 2014 / Revised: 15 April 2014 / Accepted: 18 April 2014 / Published: 12 May 2014
PDF Full-text (503 KB) | HTML Full-text | XML Full-text
Abstract
The use of architectures that implement optical switching without any need of optoelectronic conversion allows us to overcome the limits imposed by today’s electronic backplane, such as power consumption and dissipation, as well as power supply and footprint requirements. We propose a [...] Read more.
The use of architectures that implement optical switching without any need of optoelectronic conversion allows us to overcome the limits imposed by today’s electronic backplane, such as power consumption and dissipation, as well as power supply and footprint requirements. We propose a ring-resonator based optical backplane for router line-card interconnection. In particular we investigate how the scalability of the architecture is affected by the following parameters: number of line cards, switching-element round-trip losses, frequency drifting due to thermal variations, and waveguide-crossing effects. Moreover, to quantify the signal distortions introduced by filtering operations, the bit error rate for the different parameter conditions are shown in case of an on-off keying non-return-to-zero (OOK-NRZ) input signal at 10 Gb/s. Full article
(This article belongs to the Special Issue All Optical Networks for Communications)
Figures

Open AccessArticle Photonic-Based RF Transceiver for UWB Multi-Carrier Wireless Systems
Photonics 2014, 1(2), 146-153; doi:10.3390/photonics1020146
Received: 31 January 2014 / Revised: 7 May 2014 / Accepted: 9 May 2014 / Published: 22 May 2014
PDF Full-text (387 KB) | HTML Full-text | XML Full-text
Abstract
In this paper an all-optical system exploitable as the core structure for a photonic-based RF transceiver is presented. The proposed scheme is able to simultaneously perform either up- or down-conversion of multiple frequency Ultra-Wide Band (UWB) RF signals, employing a single Mode-Locking [...] Read more.
In this paper an all-optical system exploitable as the core structure for a photonic-based RF transceiver is presented. The proposed scheme is able to simultaneously perform either up- or down-conversion of multiple frequency Ultra-Wide Band (UWB) RF signals, employing a single Mode-Locking Laser (MLL). The system has been experimentally demonstrated and tested by up- and down-converting orthogonal frequency division multiplexing (OFDM) signals over a bandwidth of about 4 GHz. The scheme’s performance has been validated by measuring the error vector magnitude (EVM) of the OFDM signals over the whole considered RF spectrum (from 5 GHz to 26.5 GHz), both in up-conversion and in down-conversion. The measurements show negligible power penalties, lower than 0.5 dB. Since the proposed scheme can act either as an up- or down-converter, and it is composed by easily integratable devices, two identical structures can be combined on a single integrated platform, sharing a single MLL, to build a compact and efficient UWB transceiver. Full article
(This article belongs to the Special Issue All Optical Networks for Communications)
Figures

Open AccessArticle Polarization-Independent All-Optical Regenerator for DPSK Data
Photonics 2014, 1(2), 154-161; doi:10.3390/photonics1020154
Received: 30 January 2014 / Revised: 4 May 2014 / Accepted: 5 May 2014 / Published: 27 May 2014
PDF Full-text (374 KB) | HTML Full-text | XML Full-text
Abstract
We demonstrate polarization-independent simultaneous all-optical phase-preserving amplitude regeneration and wavelength conversion of NRZ differential phase shift keying (DPSK) data by four-wave mixing (FWM) in a semiconductor optical amplifier (SOA). The dependence upon polarization state of the signals is eliminated by using a [...] Read more.
We demonstrate polarization-independent simultaneous all-optical phase-preserving amplitude regeneration and wavelength conversion of NRZ differential phase shift keying (DPSK) data by four-wave mixing (FWM) in a semiconductor optical amplifier (SOA). The dependence upon polarization state of the signals is eliminated by using a co-polarized dual-pump architecture. Investigation on the regenerative capability vs. pumps detuning shows significant BER threshold margin improvement over 6 nm conversion range. Full article
(This article belongs to the Special Issue All Optical Networks for Communications)

Review

Jump to: Research

Open AccessReview Transport Schemes for Fiber-Wireless Technology: Transmission Performance and Energy Efficiency
Photonics 2014, 1(2), 67-82; doi:10.3390/photonics1020067
Received: 23 December 2013 / Revised: 21 March 2014 / Accepted: 24 March 2014 / Published: 16 April 2014
PDF Full-text (798 KB) | HTML Full-text | XML Full-text
Abstract
Fiber-wireless technology has been actively researched as a potential candidate for next generation broadband wireless signal distribution. Despite the popularity, this hybrid scheme has many technical challenges that impede the uptake and commercial deployment. One of the inherent issues is the transport [...] Read more.
Fiber-wireless technology has been actively researched as a potential candidate for next generation broadband wireless signal distribution. Despite the popularity, this hybrid scheme has many technical challenges that impede the uptake and commercial deployment. One of the inherent issues is the transport of the wireless signals over a predominantly digital optical network in today’s telecommunication infrastructure. Many different approaches have been introduced and demonstrated with digitized RF transport of the wireless signals being the most compatible with the existing optical fiber networks. In this paper, we review our work in the area of digitized RF transport to address the inherent issues related to analog transport in the fiber-wireless links and compare the transmission performance and energy efficiency with the other transport strategies. Full article
(This article belongs to the Special Issue All Optical Networks for Communications)
Open AccessReview Self-Homodyne Detection in Optical Communication Systems
Photonics 2014, 1(2), 110-130; doi:10.3390/photonics1020110
Received: 2 March 2014 / Revised: 28 March 2014 / Accepted: 2 April 2014 / Published: 6 May 2014
Cited by 1 | PDF Full-text (747 KB) | HTML Full-text | XML Full-text
Abstract
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 [...] Read more.
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 contributors to the optical signal-to-noise ratio penalty compared to equivalent intradyne systems, and summarize the advantages, differences and similarities between schemes using polarization-division multiplexed PTs (PDM-SHD) and those using space-division multiplexed PTs (SDM-SHD). For PDM-SHD, we review the extensive work on the transmission of advanced modulation formats and techniques to minimize the trade-off with spectral efficiency, as well as recent work on digital SHD, where the SHD receiver is combined with an polarization-diversity ID front-end receiver to provide both polarization and modulation format alignment. We then focus on SDM-SHD systems, describing experimental results using multi-core fibers (MCFs) with up to 19 cores, including high capacity transmission with broad-linewidth lasers and experiments incorporating SDM-SHD in networking. Additionally, we discuss the requirement for polarization tracking of the PTs at the receiver and path length alignment and review some variants of SHD before outlining the future challenges of self-homodyne optical transmission and gaps in current knowledge. Full article
(This article belongs to the Special Issue All Optical Networks for Communications)

Journal Contact

MDPI AG
Photonics Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
photonics@mdpi.com
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Photonics
Back to Top