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You searched for subject:(Reflectivity Division Multiplexing). Showing records 1 – 2 of 2 total matches.

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1. Mansoor, Riyadh. Crosstalk and signal integrity in ring resonator based optical add/drop multiplexers for wavelength-division-multiplexing networks.

Degree: PhD, 2015, De Montfort University

With 400 Gbps Ethernet being developed at the time of writing this thesis, all-optical networks are a solution to the increased bandwidth requirements of data communication allowing architectures to become increasingly integrated. High density integration of optical components leads to potential ‘Optical/Photonic’ electromagnetic compatibility (EMC) and signal integrity (SI) issues due to the close proximity of optical components and waveguides. Optical EMC issues are due to backscatter, crosstalk, stray light, and substrate modes. This thesis has focused on the crosstalk in Optical Add/Drop Multiplexers (OADMs) as an EMC problem. The main research question is: “How can signal integrity be improved and crosstalk effects mitigated in small-sized OADMs in order to enhance the optical EMC in all-optical networks and contribute to the increase in integration scalability?” To answer this question, increasing the crosstalk suppression bandwidth rather than maximizing the crosstalk suppression ratio is proposed in ring resonator based OADMs. Ring resonators have a small ‘real estate’ requirement and are, therefore, potentially useful for large scale integrated optical systems. A number of approaches such as over-coupled rings, vertically-coupled rings and rings with random and periodic roughness are adopted to effectively reduce the crosstalk between 10 Gbps modulated channels in OADMs. An electromagnetic simulation-driven optimization technique is proposed and used to optimize filter performance of vertically coupled single ring OADMs. A novel approach to analyse and exploit semi-periodic sidewall roughness in silicon waveguides is proposed. Grating-assisted ring resonator design is presented and optimized to increase the crosstalk suppression bandwidth.

Subjects/Keywords: 621.382; Add/drop filter; Crosstalk; Mason’s rule; Back-reflection; Grating reflectivity; Sidewall roughness.ring resonator; Wavelength Division Multiplexing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Mansoor, R. (2015). Crosstalk and signal integrity in ring resonator based optical add/drop multiplexers for wavelength-division-multiplexing networks. (Doctoral Dissertation). De Montfort University. Retrieved from http://hdl.handle.net/2086/11396

Chicago Manual of Style (16th Edition):

Mansoor, Riyadh. “Crosstalk and signal integrity in ring resonator based optical add/drop multiplexers for wavelength-division-multiplexing networks.” 2015. Doctoral Dissertation, De Montfort University. Accessed December 08, 2019. http://hdl.handle.net/2086/11396.

MLA Handbook (7th Edition):

Mansoor, Riyadh. “Crosstalk and signal integrity in ring resonator based optical add/drop multiplexers for wavelength-division-multiplexing networks.” 2015. Web. 08 Dec 2019.

Vancouver:

Mansoor R. Crosstalk and signal integrity in ring resonator based optical add/drop multiplexers for wavelength-division-multiplexing networks. [Internet] [Doctoral dissertation]. De Montfort University; 2015. [cited 2019 Dec 08]. Available from: http://hdl.handle.net/2086/11396.

Council of Science Editors:

Mansoor R. Crosstalk and signal integrity in ring resonator based optical add/drop multiplexers for wavelength-division-multiplexing networks. [Doctoral Dissertation]. De Montfort University; 2015. Available from: http://hdl.handle.net/2086/11396


Indian Institute of Science

2. Madhav, Kalaga Venu. All-Fiber Sensing Techniques For Structural Health Monitoring And Other Applications.

Degree: 2007, Indian Institute of Science

In this thesis, we explore the four aspects of fiber Bragg grating sensors: mathematical modeling of Fiber Bragg Grating response/spectral characteristics, fabrication using phase mask, application and interrogation. Applications of fiber Bragg gratings, also known as in-fiber gratings, with emphasis on their sensing capabilities, interrogation of an array of sensors and their performance in structural health monitoring scenario are documented. First, we study the process of photosensitivity phenomenon in glasses, in particular GeO2:SiO2 glasses. For mathematical modeling we consider the 1-D refractive index profile along the propagation axis of an optical fiber drawn from the preform of such glasses. These 1-D index structures exhibit a bandgap for propagation along the fiber axis. We show how the bandgap is dependent on the two structural parameters: index periodicity and effective refractive index. The mathematical model provides the characteristics of three sensor parameters -resonance wavelength also known as the Bragg wavelength (λB ), filter bandwidth (ΔλB ), and reflectivity (R). We show that the evolution of the index structure in germanosilicate glasses is dependent on the inscription parameters such as exposure time, intensity of the laser used for inscribing, the interference pattern, and coherence of the laser system. In particular, a phase mask is used as the diffffacting element to generate the required interference pattern, that is exposed on the photosensitive fiber. We present a mathematical model of the electromagnetic diffraction pattern behind the phase mask and study the effect of the limited coherence of the writing laser on the interference pattern produced by the diffracting beams from the mask. Next, we demostrate the sensing capabilities of the fiber Bragg gratings for measuring strain, temperature and magnetic fields. We report linearity of 99.7% and sensitivity of 10.35pm/◦C for the grating temperature sensor. An array of gratings assigned with non-overlapping spectral windows is inscribed in a single fiber and applied for distributed sensing of structural health monitoring of an aircraft’s composite air-brake panel. The performance of these sensors is compared with the industry standard resistance foil gauges. We report good agreement between the two gauges (FBG and RSG). In some applications it is more desirable to know the spectral content, rather than the magnitude of perturbation. Fiber Bragg gratings sensors can be used to track events that occur in a very small span of time and contain high frequencies. Such applications demand very high speed wavelength demodulation methods. We present two interrogation techniques: wavelength-shift time-stamping (WSTS) and reflectivity division multiplexing (RDM). WSTS interrogation method employs the multiple threshold-crossing technique to quantize the sensor grating fluctuations and in the process produces the time stamps at every level-cross. The time-stamps are assembled and with the a priori knowledge of the threshold levels, the strain… Advisors/Committee Members: Asokan, S.

Subjects/Keywords: Structural Health Monitoring; Optical Devices; Fiber Optics; Fiber Bragg Gratings (FBG); Optical Fibers - Photosensitivity; Fiber Bragg Grating Sensor; Fiber Bragg Grating - Mathematical Modeling; Photonic Bandgap; Fabricated Gratings; FBG Fabrication; Grating; Fiber Sensing; Reflectivity Division Multiplexing; Instrumentation

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Madhav, K. V. (2007). All-Fiber Sensing Techniques For Structural Health Monitoring And Other Applications. (Thesis). Indian Institute of Science. Retrieved from http://hdl.handle.net/2005/644

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Madhav, Kalaga Venu. “All-Fiber Sensing Techniques For Structural Health Monitoring And Other Applications.” 2007. Thesis, Indian Institute of Science. Accessed December 08, 2019. http://hdl.handle.net/2005/644.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Madhav, Kalaga Venu. “All-Fiber Sensing Techniques For Structural Health Monitoring And Other Applications.” 2007. Web. 08 Dec 2019.

Vancouver:

Madhav KV. All-Fiber Sensing Techniques For Structural Health Monitoring And Other Applications. [Internet] [Thesis]. Indian Institute of Science; 2007. [cited 2019 Dec 08]. Available from: http://hdl.handle.net/2005/644.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Madhav KV. All-Fiber Sensing Techniques For Structural Health Monitoring And Other Applications. [Thesis]. Indian Institute of Science; 2007. Available from: http://hdl.handle.net/2005/644

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.