Romeo Velarde - Academia.edu (original) (raw)

Papers by Romeo Velarde

Research paper thumbnail of Development of a Low-Cost Vibration Measurement System for Industrial Applications

Machines, 2019

Vibration-Based Condition Monitoring (VBCM) provides essential data to perform Condition-Based Ma... more Vibration-Based Condition Monitoring (VBCM) provides essential data to perform Condition-Based Maintenance for efficient, optimal, reliable, and safe industrial machinery operation. However, equipment required to perform VBCM is often relatively expensive. In this paper, a low-cost vibration measurement system based on a microcontroller platform is presented. The FRDM K64F development board was selected as the most suitable for fulfilling the system requirements. The industrial environment is highly contaminated by noise (electromagnetic, combustion, airborne, sound borne, and mechanical noise). Developing a proper antialiasing filter to reduce industrial noise is a real challenge. In order to validate the developed system, evaluations of frequency response and phase noise were carried out. Additionally, vibration measurements were recorded in the industry under different running conditions and machine configurations. Data were collected simultaneously using a standard reference sys...

Research paper thumbnail of Spectroscopic investigation of the energy transfer from europium to neodymium in fluorite crystal

Research paper thumbnail of Performance evaluation of frequency estimators for nonlinear synchronizers

GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)

The performance of three data-aided frequency estimators is evaluated for their application in no... more The performance of three data-aided frequency estimators is evaluated for their application in nonlinear synchronizers. Results are compared for the two known estimators and a proposed phase increment estimator (PIE). This estimator shows better performance in general. A possible improvement of the estimator is presented by using a decision directed (DD) approach. The PIE estimator is selected as the proper match for the DD scheme. Improvement is observed for low signal-to-noise ratio.

Research paper thumbnail of Spectroscopic Properties of Nd3+ in CaF2

Physica Status Solidi (a), 1993

Research paper thumbnail of A hybrid decoding method for short-blocklength Reed Solomon codes

1994 IEEE GLOBECOM. Communications: The Global Bridge

ABSTRACT The standard Berlekamp-Massey (1965, 1969) iterative algorithm, although the most common... more ABSTRACT The standard Berlekamp-Massey (1965, 1969) iterative algorithm, although the most commonly used decoding method for Reed-Solomon (RS) codes, is computationally complex. A novel decoding technique that combines error trapping decoding and the Berlekamp-Massey algorithm is proposed. It is demonstrated that this decoder maintains the simplicity of the error trapping decoder for the most part. Moreover, it is shown that whenever it is necessary to apply the maximum error correcting capability of the code, only a shortened Berlekamp-Massey algorithm is utilized. Substantial improvement in the decoder throughput relative to that of Berlekamp-Massey decoding is reported. Software simulation is used to verify the theoretical performance analysis

Research paper thumbnail of Distribution: SP100, Wireless Systems for Automation

... Download: CACHED: Download as a PDF. by Wayne Manges , Richard S , Lois Ferson , Brian Armstr... more ... Download: CACHED: Download as a PDF. by Wayne Manges , Richard S , Lois Ferson , Brian Armstrong , Steve Bennett , Jeorg Bertholdt , Sean Boyle , Michael Dow , Bill Drake , Rick Enns , Peter Fuhr , Barbara G. Goode , Patrick Gonia , Robert Gooch , Bob Guimarin , Toshi ...

Research paper thumbnail of Method, device and computer program product for a demodulator using a fuzzy adaptive filter (FAF) and decision feedback

Research paper thumbnail of Method, device and computer program product for a demodulator using a fuzzy adaptive filter (FAF) and decision feedback

Research paper thumbnail of Development of a Low-Cost Vibration Measurement System for Industrial Applications

Machines, 2019

Vibration-Based Condition Monitoring (VBCM) provides essential data to perform Condition-Based Ma... more Vibration-Based Condition Monitoring (VBCM) provides essential data to perform Condition-Based Maintenance for efficient, optimal, reliable, and safe industrial machinery operation. However, equipment required to perform VBCM is often relatively expensive. In this paper, a low-cost vibration measurement system based on a microcontroller platform is presented. The FRDM K64F development board was selected as the most suitable for fulfilling the system requirements. The industrial environment is highly contaminated by noise (electromagnetic, combustion, airborne, sound borne, and mechanical noise). Developing a proper antialiasing filter to reduce industrial noise is a real challenge. In order to validate the developed system, evaluations of frequency response and phase noise were carried out. Additionally, vibration measurements were recorded in the industry under different running conditions and machine configurations. Data were collected simultaneously using a standard reference system and the low-cost vibration measurement system. Results were processed using Fast Fourier Transform and Welch's method. Finally, a low-cost vibration measurement system was successfully created. The validation process demonstrates the robustness, reliability, and accuracy of this research approach. Results confirm a correlation between signal frequency spectrum obtained using both measurement systems. We also introduce new guidelines for practical data storage, communications, and validation process for vibration measurements.

Research paper thumbnail of US PATENT APPLICATION US 2003/0095610 A1

METHOD, DEVICE AND COMPUTER PROGRAM PRODUCT FOR A DEMODULATOR USING A FUZZY ADAPTIVE FILTER (FAF)... more METHOD, DEVICE AND COMPUTER
PROGRAM PRODUCT FOR A
DEMODULATOR USING A FUZZY
ADAPTIVE FILTER (FAF) AND DECISION
FEEDBACK

Research paper thumbnail of Performance Evaluation of Frequency Estimators for Nonlinear Synchronizers

The performance of three data-aided frequency estimators is evaluated for their application in no... more The performance of three data-aided frequency
estimators is evaluated for their application in nonlinear
synchronizers. Results are compared for the two known
estimators and a proposed phase increment estimator (PIE).
This estimator shows better performance in general. A possible
improvement of the estimator is presented by using a decision
directed (DD) approach. The PIE estimator is selected as the
proper match for the DD scheme. Improvement is observed for
low signal-to-noise ratio.

Research paper thumbnail of A Hybrid Decoding Method for Short-Blocklength Reed Solomon Codes

The standard Berlekamp-Massey iterative algorithm, although the most commonly used decoding metho... more The standard Berlekamp-Massey iterative
algorithm, although the most commonly used decoding method
for Reed-Solomon (RS) codes, is computationally complex. A
novel decoding technique that combines error trapping
decoding and the Berlekamp-Massey algorithm is proposed in
this article. It is demonstrated that this decoder maintains the
simplicity of the error trapping decoder for the most part.
Moreover, it is shown that whenever it is necessary to apply
the maximum error correcting capability of the code, only a
shortened Berlekamp-Massey algorithm is utilized. Substantial
improvement in the decoder throughput relative to that of
Berlekamp-Massey decoding is reported. Software simulation
is used to verify the theoretical performance analysis.

Research paper thumbnail of Spectroscopic investigation of the energy transfer from europium to neodymium in fluorite crystal

A series of spectroscopic measurements have been performed to examine the nature of the energy tr... more A series of spectroscopic measurements have been performed to examine the nature of the energy transfer process between divalent europium and trivalent neodymium ions in calcium fluoride single crystals. Measurements were taken on various samples doped with Eu + andNd + alone and co-doped with these ions. These measurements include absorption, luminescence, excitation spectra, and time-resolved response to the pulsed excitation. The measurements were carried out over a range of temperatures from 80 to 300 K.

Research paper thumbnail of Spectroscopic Properties of Nd3+ in CaF2

A spectroscopic investigation of Nd3+ in calcium fluoride host is performed to assess its feasibi... more A spectroscopic investigation of Nd3+ in calcium fluoride host is performed to assess its feasibility for laser action. The Judd-Ofeit theory is applied to measured values of absorption line strengths to obtain the intensity parameters: Ω2 = 0.87 × 10−20 cm2, Ω4 = 3.44 × 10−20 cm2, and Ω6 = 9.47 × 10−20 cm2. These intensity parameters are used to calculate the line strengths for excited-state emission from the metastable 4F3/2 state to the 4IJ′ manifolds. The calculated line strengths are then used to predict the radiative decay rates and branching ratios. The radiative lifetime of the metastable state is predicted to be 190 μs. Finally, the important working parameter X = Ω4/Ω6, known as spectroscopic quality factor, for this sample is calculated and compared with those of other Nd3+ -based laser crystals.

Research paper thumbnail of Development of a Low-Cost Vibration Measurement System for Industrial Applications

Machines, 2019

Vibration-Based Condition Monitoring (VBCM) provides essential data to perform Condition-Based Ma... more Vibration-Based Condition Monitoring (VBCM) provides essential data to perform Condition-Based Maintenance for efficient, optimal, reliable, and safe industrial machinery operation. However, equipment required to perform VBCM is often relatively expensive. In this paper, a low-cost vibration measurement system based on a microcontroller platform is presented. The FRDM K64F development board was selected as the most suitable for fulfilling the system requirements. The industrial environment is highly contaminated by noise (electromagnetic, combustion, airborne, sound borne, and mechanical noise). Developing a proper antialiasing filter to reduce industrial noise is a real challenge. In order to validate the developed system, evaluations of frequency response and phase noise were carried out. Additionally, vibration measurements were recorded in the industry under different running conditions and machine configurations. Data were collected simultaneously using a standard reference sys...

Research paper thumbnail of Spectroscopic investigation of the energy transfer from europium to neodymium in fluorite crystal

Research paper thumbnail of Performance evaluation of frequency estimators for nonlinear synchronizers

GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270)

The performance of three data-aided frequency estimators is evaluated for their application in no... more The performance of three data-aided frequency estimators is evaluated for their application in nonlinear synchronizers. Results are compared for the two known estimators and a proposed phase increment estimator (PIE). This estimator shows better performance in general. A possible improvement of the estimator is presented by using a decision directed (DD) approach. The PIE estimator is selected as the proper match for the DD scheme. Improvement is observed for low signal-to-noise ratio.

Research paper thumbnail of Spectroscopic Properties of Nd3+ in CaF2

Physica Status Solidi (a), 1993

Research paper thumbnail of A hybrid decoding method for short-blocklength Reed Solomon codes

1994 IEEE GLOBECOM. Communications: The Global Bridge

ABSTRACT The standard Berlekamp-Massey (1965, 1969) iterative algorithm, although the most common... more ABSTRACT The standard Berlekamp-Massey (1965, 1969) iterative algorithm, although the most commonly used decoding method for Reed-Solomon (RS) codes, is computationally complex. A novel decoding technique that combines error trapping decoding and the Berlekamp-Massey algorithm is proposed. It is demonstrated that this decoder maintains the simplicity of the error trapping decoder for the most part. Moreover, it is shown that whenever it is necessary to apply the maximum error correcting capability of the code, only a shortened Berlekamp-Massey algorithm is utilized. Substantial improvement in the decoder throughput relative to that of Berlekamp-Massey decoding is reported. Software simulation is used to verify the theoretical performance analysis

Research paper thumbnail of Distribution: SP100, Wireless Systems for Automation

... Download: CACHED: Download as a PDF. by Wayne Manges , Richard S , Lois Ferson , Brian Armstr... more ... Download: CACHED: Download as a PDF. by Wayne Manges , Richard S , Lois Ferson , Brian Armstrong , Steve Bennett , Jeorg Bertholdt , Sean Boyle , Michael Dow , Bill Drake , Rick Enns , Peter Fuhr , Barbara G. Goode , Patrick Gonia , Robert Gooch , Bob Guimarin , Toshi ...

Research paper thumbnail of Method, device and computer program product for a demodulator using a fuzzy adaptive filter (FAF) and decision feedback

Research paper thumbnail of Method, device and computer program product for a demodulator using a fuzzy adaptive filter (FAF) and decision feedback

Research paper thumbnail of Development of a Low-Cost Vibration Measurement System for Industrial Applications

Machines, 2019

Vibration-Based Condition Monitoring (VBCM) provides essential data to perform Condition-Based Ma... more Vibration-Based Condition Monitoring (VBCM) provides essential data to perform Condition-Based Maintenance for efficient, optimal, reliable, and safe industrial machinery operation. However, equipment required to perform VBCM is often relatively expensive. In this paper, a low-cost vibration measurement system based on a microcontroller platform is presented. The FRDM K64F development board was selected as the most suitable for fulfilling the system requirements. The industrial environment is highly contaminated by noise (electromagnetic, combustion, airborne, sound borne, and mechanical noise). Developing a proper antialiasing filter to reduce industrial noise is a real challenge. In order to validate the developed system, evaluations of frequency response and phase noise were carried out. Additionally, vibration measurements were recorded in the industry under different running conditions and machine configurations. Data were collected simultaneously using a standard reference system and the low-cost vibration measurement system. Results were processed using Fast Fourier Transform and Welch's method. Finally, a low-cost vibration measurement system was successfully created. The validation process demonstrates the robustness, reliability, and accuracy of this research approach. Results confirm a correlation between signal frequency spectrum obtained using both measurement systems. We also introduce new guidelines for practical data storage, communications, and validation process for vibration measurements.

Research paper thumbnail of US PATENT APPLICATION US 2003/0095610 A1

METHOD, DEVICE AND COMPUTER PROGRAM PRODUCT FOR A DEMODULATOR USING A FUZZY ADAPTIVE FILTER (FAF)... more METHOD, DEVICE AND COMPUTER
PROGRAM PRODUCT FOR A
DEMODULATOR USING A FUZZY
ADAPTIVE FILTER (FAF) AND DECISION
FEEDBACK

Research paper thumbnail of Performance Evaluation of Frequency Estimators for Nonlinear Synchronizers

The performance of three data-aided frequency estimators is evaluated for their application in no... more The performance of three data-aided frequency
estimators is evaluated for their application in nonlinear
synchronizers. Results are compared for the two known
estimators and a proposed phase increment estimator (PIE).
This estimator shows better performance in general. A possible
improvement of the estimator is presented by using a decision
directed (DD) approach. The PIE estimator is selected as the
proper match for the DD scheme. Improvement is observed for
low signal-to-noise ratio.

Research paper thumbnail of A Hybrid Decoding Method for Short-Blocklength Reed Solomon Codes

The standard Berlekamp-Massey iterative algorithm, although the most commonly used decoding metho... more The standard Berlekamp-Massey iterative
algorithm, although the most commonly used decoding method
for Reed-Solomon (RS) codes, is computationally complex. A
novel decoding technique that combines error trapping
decoding and the Berlekamp-Massey algorithm is proposed in
this article. It is demonstrated that this decoder maintains the
simplicity of the error trapping decoder for the most part.
Moreover, it is shown that whenever it is necessary to apply
the maximum error correcting capability of the code, only a
shortened Berlekamp-Massey algorithm is utilized. Substantial
improvement in the decoder throughput relative to that of
Berlekamp-Massey decoding is reported. Software simulation
is used to verify the theoretical performance analysis.

Research paper thumbnail of Spectroscopic investigation of the energy transfer from europium to neodymium in fluorite crystal

A series of spectroscopic measurements have been performed to examine the nature of the energy tr... more A series of spectroscopic measurements have been performed to examine the nature of the energy transfer process between divalent europium and trivalent neodymium ions in calcium fluoride single crystals. Measurements were taken on various samples doped with Eu + andNd + alone and co-doped with these ions. These measurements include absorption, luminescence, excitation spectra, and time-resolved response to the pulsed excitation. The measurements were carried out over a range of temperatures from 80 to 300 K.

Research paper thumbnail of Spectroscopic Properties of Nd3+ in CaF2

A spectroscopic investigation of Nd3+ in calcium fluoride host is performed to assess its feasibi... more A spectroscopic investigation of Nd3+ in calcium fluoride host is performed to assess its feasibility for laser action. The Judd-Ofeit theory is applied to measured values of absorption line strengths to obtain the intensity parameters: Ω2 = 0.87 × 10−20 cm2, Ω4 = 3.44 × 10−20 cm2, and Ω6 = 9.47 × 10−20 cm2. These intensity parameters are used to calculate the line strengths for excited-state emission from the metastable 4F3/2 state to the 4IJ′ manifolds. The calculated line strengths are then used to predict the radiative decay rates and branching ratios. The radiative lifetime of the metastable state is predicted to be 190 μs. Finally, the important working parameter X = Ω4/Ω6, known as spectroscopic quality factor, for this sample is calculated and compared with those of other Nd3+ -based laser crystals.