Walid Y. Alali - Academia.edu (original) (raw)

Papers by Walid Y. Alali

Electronic Instrument, 1988

Solid State based metering systems could be implemented thanks to microelectronic technologies. T... more Solid State based metering systems could be implemented thanks to microelectronic technologies. This paper describes an ASIC design that implements all but the analog portion of a watt-hour meter. This ASIC, created using APBB [1] technology, is meant to be used in conjunction with the Ferraris power meter in a hybrid telecounting system or in a fully static watt-hour meter. The Ferraris power meter's disk turn count is the data that the ASIC receives and processes in the first scenario; it is transmitted from the latter to the ASIC via optical interconnection. In the second scenario, a fully static power meter is used, and the ASIC receives two 12-bit words that represent the current and voltage values.

Electronic Letter, 1988

Abstract: A signal processing application of a dual board is used for the control of permanent ma... more Abstract: A signal processing application of a dual board is used for the control of permanent magnet synchronous motors (PMSMs). The circuit of the dual board has been tested using a 1·5 kW PMSM and characterised over motor speed ranges up to 3000 rpm. The use of single-chip microcontrollers has proven to be a compact, high-performance solution for AC motor closed-loop control.

Electronic Power System Research, 1987

A new PWM method for unity power factor C/DC converter is presented in this paper. It is sinusoid... more A new PWM method for unity power factor C/DC converter is presented in this paper. It is sinusoid pulse width modulation in case the load includes 2nd harmonic ripple current. The main circuit consists of an uncontrolled singlephase rectifier bridge followed by a buck chopper. An 8098 single-chip microprocessor is employed in this control strategy. The hardware and software of the control system are introduced. In the end, the paper gives the satisfied experimental results.

The objective of this paper is to describe the design of a wide-bandwidth, noise-resistant digita... more The objective of this paper is to describe the design of a wide-bandwidth, noise-resistant digital phase meter. The principle of the design is based on phase compensation while the phase shifter is digitally controlled is the main core of the paper and is described in detail. The design is accurate for more the -6 dB signal-to-noise ratios,

IEEE Transactions on Automatic Control, 1988

Abstract: This paper explains a new interactive power meter achieved by TMS 320 a digital signal ... more Abstract: This paper explains a new interactive power meter achieved by TMS 320 a digital signal processing (DSP) technique that defines equation conditions. Q_x = √ { V_rms^2 ∑_(n=1)^∞〖( Qn Vn)^2 }〗 for the importance n harmonics. The definition of reactive current is useful because by reduces its value, while the maximum PF (power factor) can be obtained for non-genetic systems. To achieve the simultaneous current and voltage spectra, we used for the 2 sets of actual data, a discrete Fourier transform (DFT), the current and voltage spectra are taken simultaneously and then processed both spectra of the imaginary and real parts to obtain the term of the equation above. Using a single-chip microcomputer (TMS320) to investigate some of the results of the simulated measurements.

IEEE Journal of Solid-State Circuits, 1990

It is suggested to use zero crossing detectors to build a high-precision power-factor meter. Low ... more It is suggested to use zero crossing detectors to build a high-precision power-factor meter. Low pass filters are suggested to stop this error source after the influence of input signal distortion is examined. Based on the measurement of voltage, current, and power factor, this system is also proposed as a new type of power standard meter.

IEEE Transactions on Signal Processing, 1991

The task of algorithm implementation in several applications of signal processing is the most int... more The task of algorithm implementation in several applications of signal processing is the most interesting task for the engineers of the DSP field. The pressure most engineers have and looking for is how to solve these algorithms with less time and pain. This paper implements a technique and tools created to use with the microprocessor TMS 320 as a part of the DSP family which is helpful and expedited for such development. Using the Language C compiler helps to accelerate the implementation, while the hardware and software improvement tools address debugging more leniently. Some algorithm implementation techniques are examined in the context of particular applications.

IEEE Transactions on Signal Processing, 1992

This paper is a novel digital signal processing software of the advanced conversion of text-to-sp... more This paper is a novel digital signal processing software of the advanced conversion of text-to-speech synthesis technology, which has been available as a range of hardware products for more than ten years, to software. It was initially created as a replacement for character cell terminals and telephony applications, but it is now also used to give people who are visually impaired access to information. With a digital formant synthesizer used to mimic the human vocal tract, text-to-speech quality is very high in both understandability and naturalness. The computational requirements of this synthesizer put a tremendous amount of strain on a workstation in the days before extremely fast processors. Multiple text streams were simultaneously converted to speech for this study using a Digital Equipment AlphaModel 600 workstation. Modern RISC processor power enables applications to freely output speech. A text-to-speech application programming interface (API) is now necessary as a result of this capability. The TTS software API we created is compatible with a wide range of hardware and operating systems. The architecture of the TTS software is described in this paper. Additionally, the API is mentioned. Finally, we describe our experience porting the TTS code base from the previous hardware platforms.

IEEE Journal of Solid-State Circuits, 1990

An innovative adaptive line enhancer (ALE) structure is presented in this work. The adaptive filt... more An innovative adaptive line enhancer (ALE) structure is presented in this work. The adaptive filter's autoregressive-moving average (ARMA) structure is based on traditional Laguerre orthogonal functions. The orthogonal set's poles' frequencies and radii allow for tuning. Higher-order statistics are used to tune these terms in this contribution. Fourth-order cumulants' qualities are used to help with harmonic retrieval of the sinusoids embedded in the input signal. Since the feed-forward filter parameters are linearly connected to the filter output, further adaption of them is simple. Stability, brevity, and robustness in the presence of noise are expected benefits. Results from simulations are presented to demonstrate typical performance.

Proceedings of the IEEE, 1989

Due to the need for a flexible vocabulary and the high cost of collecting speech corpora, vocabul... more Due to the need for a flexible vocabulary and the high cost of collecting speech corpora, vocabulary independence of speech recognition systems has grown to be a significant issue. We describe the steps required to reach the objective of vocabulary-independent speech recognition and discuss our experimental experience with telephone speech recognition. There were two sets of experiments: 1) Wcommand recognition, where we compared vocabulary-independent (VI) and vocabulary-dependent (VD) systems as well as phonetic and word-based systems, and 2) 42-city name recognition, where our vocabulary independent recognition performance (8.5% W. Err.) was very close to the VD performance (8%) of the Oregon Graduate Institute (OGI), which was reported by OGI, but significantly better than the VI performance (18%). Finally, we can say that some progress has been made. We identify the areas for improvement that are likely to move us closer to the goal of vocabulary independence, but much work needs to be done.

IEEE Transactions on Circuits and Systems, 1989

We discuss the use of multi-rate FIR filters in radio frequency (RF) transient spectroscopy as we... more We discuss the use of multi-rate FIR filters in radio frequency (RF) transient spectroscopy as well as the implementation challenges these multi-rate filters face when used in this application to reduce the sampling rate (decimation) and raise the sampling rate (interpolation). On a Texas Instruments TMS320-C30 DSP processor, all implementation measurements given here were carried out.

Abstract: This paper explains a new interactive power meter achieved by TMS 320 a digital signal ... more Abstract: This paper explains a new interactive power meter achieved by TMS 320 a digital signal processing (DSP) technique that defines equation conditions. Q_x = √ { V_rms^2 ∑_(n=1)^∞〖( Qn Vn)^2 }〗 for the importance n harmonics. The definition of reactive current is useful because by reducing its value, while the maximum PF (power factor) can be obtained for non-genetic systems. To achieve the simultaneously current and voltage spectra, we used for the 2 sets of actual data, a discrete Fourier transform (DFT), the current and voltage spectra are taken simultaneously and then processed both spectra of the imaginary and real parts to obtain the term of the equation above. Using a single chip microcomputer (TMS320) to investigate some of the results of the simulated measurements.

IEEE Transactions on Instrumentation and Measurement, 1986

This paper introduces the design of a Single-phase watthour meter auto-calibrating. The important... more This paper introduces the design of a Single-phase watthour meter auto-calibrating. The important advantage of the watthour scale is the multiplication is done by the newly developed self-calibration multiplier (SCM) with superior stability. The self-calibration multiplier IC applies an analogue multiplier to perform the multiplication, detects and also compensates for large sources of error caused by changing the multiplication parameter including the output offset. According to this result, the self-calibration multiplier has stable input and output characteristics. The correction of the multiplication factor is based on an IC reference voltage that uses the Zener diode. Consequently, the stability of the self-calibration multiplier and the meter depends on the reference voltage stability. While the other pieces are additional circuits to adjust the zero load and the unnecessary full load.

Journal of Business Economics and Management, Mar 12, 1986

This paper introduces the design of a Single-phase watthour meter auto-calibrating. The important... more This paper introduces the design of a Single-phase watthour meter auto-calibrating. The important advantage of the watthour scale is the multiplication is done by the newly developed self-calibration multiplier (SCM) with superior stability. The self-calibration multiplier IC applies an analogue multiplier to perform the multiplication, detects and also compensates for large sources of error caused by changing the multiplication parameter including the out-put offset.
According to this result, the self-calibration multiplier has stable input and output characteristics. The correction of the multiplication factor is based on an IC reference voltage that uses the Zener diode. Consequently, the stability of the self-calibration multiplier and the meter depends on the reference voltage stability. While the other pieces are additional circuits to adjust the zero load and the unnecessary full load.

Solar & Wind Technoloyy Vol. 3, No. 4, pp. 319-321, 1986, 1986

This paper deals with the design and implementation of a hybrid processor required to provide dig... more This paper deals with the design and implementation of a hybrid processor required to provide digitally a number proportional to the geometric mean temperature of the solar pond. It introduces the design and implementation of a suitable non-linear analog-to-digital converter (NL-ADC) arrangement to deal with this task.

Journal of Nondestructive Evaluation, Vol. 5, No. 2, , 1986

This paper describes a microprocessor-controlled three-phase digital meter. The wattmeter is bas... more This paper describes a microprocessor-controlled three-phase digital meter. The wattmeter is based on the sampling method and, on analogue-to-digital conversion; a single A/D converter ten-bit, built into the microprocessor is used. Transformer accuracy is demonstrated by overlaying noise on current and voltage signals and reducing uncertainty with an external resistive voltage divider. The wide range of current of passing voltage signals, in proportion to the input currents, through a programmable gain amplifier. The total counter pigment is not more than 0.1 per cent.

Electronic Instrument, 1988

Solid State based metering systems could be implemented thanks to microelectronic technologies. T... more Solid State based metering systems could be implemented thanks to microelectronic technologies. This paper describes an ASIC design that implements all but the analog portion of a watt-hour meter. This ASIC, created using APBB [1] technology, is meant to be used in conjunction with the Ferraris power meter in a hybrid telecounting system or in a fully static watt-hour meter. The Ferraris power meter's disk turn count is the data that the ASIC receives and processes in the first scenario; it is transmitted from the latter to the ASIC via optical interconnection. In the second scenario, a fully static power meter is used, and the ASIC receives two 12-bit words that represent the current and voltage values.

Electronic Letter, 1988

Abstract: A signal processing application of a dual board is used for the control of permanent ma... more Abstract: A signal processing application of a dual board is used for the control of permanent magnet synchronous motors (PMSMs). The circuit of the dual board has been tested using a 1·5 kW PMSM and characterised over motor speed ranges up to 3000 rpm. The use of single-chip microcontrollers has proven to be a compact, high-performance solution for AC motor closed-loop control.

Electronic Power System Research, 1987

A new PWM method for unity power factor C/DC converter is presented in this paper. It is sinusoid... more A new PWM method for unity power factor C/DC converter is presented in this paper. It is sinusoid pulse width modulation in case the load includes 2nd harmonic ripple current. The main circuit consists of an uncontrolled singlephase rectifier bridge followed by a buck chopper. An 8098 single-chip microprocessor is employed in this control strategy. The hardware and software of the control system are introduced. In the end, the paper gives the satisfied experimental results.

The objective of this paper is to describe the design of a wide-bandwidth, noise-resistant digita... more The objective of this paper is to describe the design of a wide-bandwidth, noise-resistant digital phase meter. The principle of the design is based on phase compensation while the phase shifter is digitally controlled is the main core of the paper and is described in detail. The design is accurate for more the -6 dB signal-to-noise ratios,

IEEE Transactions on Automatic Control, 1988

Abstract: This paper explains a new interactive power meter achieved by TMS 320 a digital signal ... more Abstract: This paper explains a new interactive power meter achieved by TMS 320 a digital signal processing (DSP) technique that defines equation conditions. Q_x = √ { V_rms^2 ∑_(n=1)^∞〖( Qn Vn)^2 }〗 for the importance n harmonics. The definition of reactive current is useful because by reduces its value, while the maximum PF (power factor) can be obtained for non-genetic systems. To achieve the simultaneous current and voltage spectra, we used for the 2 sets of actual data, a discrete Fourier transform (DFT), the current and voltage spectra are taken simultaneously and then processed both spectra of the imaginary and real parts to obtain the term of the equation above. Using a single-chip microcomputer (TMS320) to investigate some of the results of the simulated measurements.

IEEE Journal of Solid-State Circuits, 1990

It is suggested to use zero crossing detectors to build a high-precision power-factor meter. Low ... more It is suggested to use zero crossing detectors to build a high-precision power-factor meter. Low pass filters are suggested to stop this error source after the influence of input signal distortion is examined. Based on the measurement of voltage, current, and power factor, this system is also proposed as a new type of power standard meter.

IEEE Transactions on Signal Processing, 1991

The task of algorithm implementation in several applications of signal processing is the most int... more The task of algorithm implementation in several applications of signal processing is the most interesting task for the engineers of the DSP field. The pressure most engineers have and looking for is how to solve these algorithms with less time and pain. This paper implements a technique and tools created to use with the microprocessor TMS 320 as a part of the DSP family which is helpful and expedited for such development. Using the Language C compiler helps to accelerate the implementation, while the hardware and software improvement tools address debugging more leniently. Some algorithm implementation techniques are examined in the context of particular applications.

IEEE Transactions on Signal Processing, 1992

This paper is a novel digital signal processing software of the advanced conversion of text-to-sp... more This paper is a novel digital signal processing software of the advanced conversion of text-to-speech synthesis technology, which has been available as a range of hardware products for more than ten years, to software. It was initially created as a replacement for character cell terminals and telephony applications, but it is now also used to give people who are visually impaired access to information. With a digital formant synthesizer used to mimic the human vocal tract, text-to-speech quality is very high in both understandability and naturalness. The computational requirements of this synthesizer put a tremendous amount of strain on a workstation in the days before extremely fast processors. Multiple text streams were simultaneously converted to speech for this study using a Digital Equipment AlphaModel 600 workstation. Modern RISC processor power enables applications to freely output speech. A text-to-speech application programming interface (API) is now necessary as a result of this capability. The TTS software API we created is compatible with a wide range of hardware and operating systems. The architecture of the TTS software is described in this paper. Additionally, the API is mentioned. Finally, we describe our experience porting the TTS code base from the previous hardware platforms.

IEEE Journal of Solid-State Circuits, 1990

An innovative adaptive line enhancer (ALE) structure is presented in this work. The adaptive filt... more An innovative adaptive line enhancer (ALE) structure is presented in this work. The adaptive filter's autoregressive-moving average (ARMA) structure is based on traditional Laguerre orthogonal functions. The orthogonal set's poles' frequencies and radii allow for tuning. Higher-order statistics are used to tune these terms in this contribution. Fourth-order cumulants' qualities are used to help with harmonic retrieval of the sinusoids embedded in the input signal. Since the feed-forward filter parameters are linearly connected to the filter output, further adaption of them is simple. Stability, brevity, and robustness in the presence of noise are expected benefits. Results from simulations are presented to demonstrate typical performance.

Proceedings of the IEEE, 1989

Due to the need for a flexible vocabulary and the high cost of collecting speech corpora, vocabul... more Due to the need for a flexible vocabulary and the high cost of collecting speech corpora, vocabulary independence of speech recognition systems has grown to be a significant issue. We describe the steps required to reach the objective of vocabulary-independent speech recognition and discuss our experimental experience with telephone speech recognition. There were two sets of experiments: 1) Wcommand recognition, where we compared vocabulary-independent (VI) and vocabulary-dependent (VD) systems as well as phonetic and word-based systems, and 2) 42-city name recognition, where our vocabulary independent recognition performance (8.5% W. Err.) was very close to the VD performance (8%) of the Oregon Graduate Institute (OGI), which was reported by OGI, but significantly better than the VI performance (18%). Finally, we can say that some progress has been made. We identify the areas for improvement that are likely to move us closer to the goal of vocabulary independence, but much work needs to be done.

IEEE Transactions on Circuits and Systems, 1989

We discuss the use of multi-rate FIR filters in radio frequency (RF) transient spectroscopy as we... more We discuss the use of multi-rate FIR filters in radio frequency (RF) transient spectroscopy as well as the implementation challenges these multi-rate filters face when used in this application to reduce the sampling rate (decimation) and raise the sampling rate (interpolation). On a Texas Instruments TMS320-C30 DSP processor, all implementation measurements given here were carried out.

Abstract: This paper explains a new interactive power meter achieved by TMS 320 a digital signal ... more Abstract: This paper explains a new interactive power meter achieved by TMS 320 a digital signal processing (DSP) technique that defines equation conditions. Q_x = √ { V_rms^2 ∑_(n=1)^∞〖( Qn Vn)^2 }〗 for the importance n harmonics. The definition of reactive current is useful because by reducing its value, while the maximum PF (power factor) can be obtained for non-genetic systems. To achieve the simultaneously current and voltage spectra, we used for the 2 sets of actual data, a discrete Fourier transform (DFT), the current and voltage spectra are taken simultaneously and then processed both spectra of the imaginary and real parts to obtain the term of the equation above. Using a single chip microcomputer (TMS320) to investigate some of the results of the simulated measurements.

IEEE Transactions on Instrumentation and Measurement, 1986

This paper introduces the design of a Single-phase watthour meter auto-calibrating. The important... more This paper introduces the design of a Single-phase watthour meter auto-calibrating. The important advantage of the watthour scale is the multiplication is done by the newly developed self-calibration multiplier (SCM) with superior stability. The self-calibration multiplier IC applies an analogue multiplier to perform the multiplication, detects and also compensates for large sources of error caused by changing the multiplication parameter including the output offset. According to this result, the self-calibration multiplier has stable input and output characteristics. The correction of the multiplication factor is based on an IC reference voltage that uses the Zener diode. Consequently, the stability of the self-calibration multiplier and the meter depends on the reference voltage stability. While the other pieces are additional circuits to adjust the zero load and the unnecessary full load.

Journal of Business Economics and Management, Mar 12, 1986

This paper introduces the design of a Single-phase watthour meter auto-calibrating. The important... more This paper introduces the design of a Single-phase watthour meter auto-calibrating. The important advantage of the watthour scale is the multiplication is done by the newly developed self-calibration multiplier (SCM) with superior stability. The self-calibration multiplier IC applies an analogue multiplier to perform the multiplication, detects and also compensates for large sources of error caused by changing the multiplication parameter including the out-put offset.
According to this result, the self-calibration multiplier has stable input and output characteristics. The correction of the multiplication factor is based on an IC reference voltage that uses the Zener diode. Consequently, the stability of the self-calibration multiplier and the meter depends on the reference voltage stability. While the other pieces are additional circuits to adjust the zero load and the unnecessary full load.

Solar & Wind Technoloyy Vol. 3, No. 4, pp. 319-321, 1986, 1986

This paper deals with the design and implementation of a hybrid processor required to provide dig... more This paper deals with the design and implementation of a hybrid processor required to provide digitally a number proportional to the geometric mean temperature of the solar pond. It introduces the design and implementation of a suitable non-linear analog-to-digital converter (NL-ADC) arrangement to deal with this task.

Journal of Nondestructive Evaluation, Vol. 5, No. 2, , 1986

This paper describes a microprocessor-controlled three-phase digital meter. The wattmeter is bas... more This paper describes a microprocessor-controlled three-phase digital meter. The wattmeter is based on the sampling method and, on analogue-to-digital conversion; a single A/D converter ten-bit, built into the microprocessor is used. Transformer accuracy is demonstrated by overlaying noise on current and voltage signals and reducing uncertainty with an external resistive voltage divider. The wide range of current of passing voltage signals, in proportion to the input currents, through a programmable gain amplifier. The total counter pigment is not more than 0.1 per cent.