Machine Learning Approaches to Historic Music Restoration

In 1889, a representative of Thomas Edison recorded Johannes Brahms playing a piano arrangement of his piece titled “Hungarian Dance No. 1”. This recording acts as a window into how musical masters played in the 19th century. Yet, due to years of damage on the original recording medium of a wax cylinder, it was un-listenable by the time it was digitized into WAV format. This thesis presents machine learning approaches to an audio restoration system for historic music, which aims to convert this poor-quality Brahms piano recording into a higher quality one. Digital signal processing is paired with two machine learning approaches: non-negative matrix factorization and deep neural networks. Our results show the advantages and disadvantages of our approaches, when we compare them to a benchmark restoration of the same recording made by the Center for Computer Research in Music and Acoustics at Stanford University. They also show how this system provides the restoration potential for a wide range of historic music artifacts like this recording, requiring minimal overhead made possible by machine learning. Finally, we go into possible future improvements to these approaches

Advancements of MultiRate Signal processing for Wireless Communication Networks: Current State Of the Art

With the hasty growth of internet contact and voice and information centric communications, many contact technologies have been urbanized to meet the stringent insist of high speed information transmission and viaduct the wide bandwidth gap among ever-increasing high-data-rate core system and bandwidth-hungry end-user complex. To make efficient consumption of the limited bandwidth of obtainable access routes and cope with the difficult channel environment, several standards have been projected for a variety of broadband access scheme over different access situation (twisted pairs, coaxial cables, optical fibers, and unchanging or mobile wireless admittance). These access situations may create dissimilar channel impairments and utter unique sets of signal dispensation algorithms and techniques to combat precise impairments. In the intended and implementation sphere of those systems, many research issues arise. In this paper we present advancements of multi-rate indication processing methodologies that are aggravated by this design trend. The thesis covers the contemporary confirmation of the current literature on intrusion suppression using multi-rate indication in wireless communiquE9; networks

A survey on OFDM-based elastic core optical networking

Orthogonal frequency-division multiplexing (OFDM) is a modulation technology that has been widely adopted in many new and emerging broadband wireless and wireline communication systems. Due to its capability to transmit a high-speed data stream using multiple spectral-overlapped lower-speed subcarriers, OFDM technology offers superior advantages of high spectrum efficiency, robustness against inter-carrier and inter-symbol interference, adaptability to server channel conditions, etc. In recent years, there have been intensive studies on optical OFDM (O-OFDM) transmission technologies, and it is considered a promising technology for future ultra-high-speed optical transmission. Based on O-OFDM technology, a novel elastic optical network architecture with immense flexibility and scalability in spectrum allocation and data rate accommodation could be built to support diverse services and the rapid growth of Internet traffic in the future. In this paper, we present a comprehensive survey on OFDM-based elastic optical network technologies, including basic principles of OFDM, O-OFDM technologies, the architectures of OFDM-based elastic core optical networks, and related key enabling technologies. The main advantages and issues of OFDM-based elastic core optical networks that are under research are also discussed

Amplificador de Potencia de Alto Rendimiento para Transmisores EER

Se presenta un amplificador de potencia de alto rendimiento específicamente diseñado para aplicaciones EER (Envelope Elimination Restoration) en transmisores de HF. El amplificador se compone de dos subsistemas: Un amplificador clase-E de banda ancha para HF (B = 40%, POUT = 50W @ 7.5 MHz, ηOV > 90%) excitado por un driver también de banda ancha que amplifica la componente de fase de la señal y un amplificador de envolvente derivado de un amplificador clase-D de audio (o clase-S) que presenta un rendimiento total mejor que el 90% para la mayor parte de su margen de salida y un nivel de intermodulación IMD de -30 dBc (prueba de dos tonos). El amplificador completo es capaz de obtener un rendimiento total ηOV > 80% con una potencia de salida de pico PEP = 50W @ 7.5 MHz en un ancho de banda fraccional B = 40%. Antes de realimentación el amplificador presenta un valor de linealidad para una prueba de dos tonos comprendido entre -28 dBc y -35 dBc

A Practical Class S Power Amplifier for High Frequency Transmitters

Digital signal processing (DSP) techniques are being incorporated in the design of modern power amplifiers (PA) and as the speed of DSP advances it is envisioned that DSP will develop to a point where algorithms will provide signals at RF particularly for switching amplifiers. The digital transmitter has many potential benefits such as the absence of aging or tuning problems, reconfigurability, programmability as well as ease of integration and testing. In this paper a new class S RF power amplifier architecture is proposed for use in high frequency transmitters and is not restricted by the requirement for the square wave modulator to have a sampling rate of 4 times the carrier frequency

Development of a Technique for Restoring the Fidelity of Distorted Playback Audio Signal from Analog Cassette Tape

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI linkA simple yet elegant analog based technique for restoring the fidelity of playback audio signals emanating from magnetic cassette tapes is presented. The technique makes use of information from the high frequency bias signal in magnetic cassette tapes to correct for errors in the playback audio signal. Performance evaluation of the developed technique shows that the technique can correct for errors due to noise, scratches on the tape surface, clipping, and non-linear distortion. The developed technique will be valuable in restoring the fidelity of playback audio signal from magnetic cassette tapes stored in archives and private homes

Novel Approach For Hybrid-Multi Level Filter Design For Wireless Applications

Less time and less delay is required for fast processing for filter. The one challenge in processing of image we design a matched filter based algorithm. That is resilient to variation in position determination. The second challenge is to fast process of filter. The match filter works to identify the passion of beam result and compared to that obtaining using the centroiding technique. This process required extra processing time for each beam. So, for fast implementation processing and less delay time we explore the possibility of using a field programming logic array and parallels combination of each delay block to speed up this computation. The second objective can achieve by the parallel hardware used that provides significant performance improvement over processing. This paper describes the development of match filter with less delay and fast processing

Design of quadrature mirror filter banks with canonical signed digit coefficients using genetic algorithms.

This thesis is about the use of a genetic algorithm to design QMF bank with canonical signed digit coefficients. A filter bank has applications in areas like video and audio coding, data communication, etc. Filter bank design is a multiobjective optimization problem. The performance depends on the reconstruction error of the overall filter bank and the individual performance of the composing lowpass filter. In this thesis we have used reconstruction error of the overall filter bank as our main objective and passband error, stopband error, stopband and passband ripples and transition width of the individual lowpass filter as constraints. Therefore filter bank design can be formulated as single objective multiple constraint optimization problem. A unique genetic algorithm is developed to optimize filer bank coefficients such that the corresponding system\u27s response matches that of an ideal system with an additional constraint that all coefficients are in canonical signed digit (CSD) format. A special restoration technique is used to restore the CSD format of the coefficients after crossover and mutation operators in Genetic algorithm. The proposed restoration technique maintains the specified word length and the maximum number of nonzero digits in filter banks coefficients. Experimental results are presented at the end. It is demonstrated that the designed genetic algorithm is reliable, and efficient for designing QMF banks.Dept. of Electrical and Computer Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2004 .U67. Source: Masters Abstracts International, Volume: 43-05, page: 1785. Thesis (M.A.Sc.)--University of Windsor (Canada), 2004