A. M. Hamza

A. M. Hamza

University of New Brunswick

H-index: 17

North America-Canada

About A. M. Hamza

A. M. Hamza, With an exceptional h-index of 17 and a recent h-index of 11 (since 2020), a distinguished researcher at University of New Brunswick, specializes in the field of theoretical plasma physics.

His recent articles reflect a diverse array of research interests and contributions to the field:

Two‐component phase scintillation spectra in the auroral region: Observations and model

Spectral characteristics of phase fluctuations at high latitude

Inferred Ionospheric irregularity scales from amplitude scintillation

Turbulence Signatures in High‐Latitude Ionospheric Scintillation

On the moments of probability distribution function of amplitude scintillation in the polar region

A Bayesian Inference‐Based Empirical Model for Scintillation Indices for High‐Latitude

On the latitude-dependence of the GPS phase variation index in the polar region

Solar cycle variations of GPS amplitude scintillation for the polar region

A. M. Hamza Information

University

University of New Brunswick

Position

___

Citations(all)

1312

Citations(since 2020)

380

Cited By

1388

hIndex(all)

17

hIndex(since 2020)

11

i10Index(all)

34

i10Index(since 2020)

11

Email

University Profile Page

University of New Brunswick

A. M. Hamza Skills & Research Interests

theoretical plasma physics

Top articles of A. M. Hamza

Two‐component phase scintillation spectra in the auroral region: Observations and model

Authors

Abdelhaq M Hamza,Kaili Song,Karim Meziane,PT Jayachandran

Journal

Journal of Geophysical Research: Space Physics

Published Date

2024/1

The random amplitude and phase fluctuations observed in trans‐ionospheric radio signals are caused by the presence of electron density irregularities in the ionosphere. Ground‐based measurements of radio wave signals provide information about the medium through which these signals propagate. The Canadian High Arctic Ionospheric Network (CHAIN) Global Position System (GPS) receivers record radio signals emitted by the GPS satellites, enabling the study of their spectral characteristics. This study presents examples of phase spectra with two power‐law components. These components exhibit steeper spectral slopes at higher frequencies and shallower ones at lower frequencies. To be more specific, we conducted a spectral characterization of sixty one (61) events recorded by the CHAIN Churchill GPS receiver, which is located in the auroral oval. When fluctuations above the background level are only …

Spectral characteristics of phase fluctuations at high latitude

Authors

K Song,AM Hamza,PT Jayachandran,K Meziane,A Kashcheyev

Journal

Journal of Geophysical Research: Space Physics

Published Date

2023/9

It has long been established that ionospheric electron density irregularities cause random rapid amplitude and phase fluctuations in trans‐ionospheric radio signals. Various types of ground‐based measurements, including radar and Global Navigation Satellite System (GNSS) receivers, have been utilized to gain insights into the plasma mechanisms that could lead to the development of these ionospheric irregularities. The spectral characteristics of radio wave signals emitted by GNSSs and detected by the Canadian High Arctic Ionospheric Network Global Positioning System (GPS) receivers are analyzed to try and identify the spectral signatures of the ionospheric plasma irregularities. In the polar region, we have confirmed that phase fluctuations in the GPS signal are not always accompanied by amplitude fluctuations. For the first time, a systematic comparison is conducted on the spectral properties of phase …

Inferred Ionospheric irregularity scales from amplitude scintillation

Authors

Karim Meziane,Abdelhaq M. Hamza,Jayachandran Tayyil P.

Published Date

2023/4/23

The analysis of the structure function of a GNSS signal amplitude measured on the ground has revealed that ionospheric scintillation could be considered a proxy for ionospheric turbulence. More precisely, and in a recent report, the existence of a linear range with respect to the time lag in the structure function has been highlighted. In this context, the inertial-range analog has been determined from the analysis of a large set of scintillation events collected over several days from Pond Inlet located in the northern polar region and from Sao Paolo located at 23.2 degrees South of the Equator. At high latitude, we found that the mean value of the first-order scaling exponent is H= 0.55±0.07, while a low altitude H is typically larger with H= 0.84±. 11. This result clearly indicates that the long-time lag positive correlation remains persistent in the low latitude region. At high latitude however, both negative and positive long …

Turbulence Signatures in High‐Latitude Ionospheric Scintillation

Authors

K Meziane,AM Hamza,PT Jayachandran

Journal

Journal of Geophysical Research: Space Physics

Published Date

2023/1

Ground‐based amplitude measurements of Global Navigation Satellite System signal during ionospheric scintillation are analyzed using prevalent data analysis tools developed in the fields of fluid and plasma turbulence. One such tool is the structure function of order q, with q = 1 to q = 6, which reduces to the computation of the second‐order difference in the GPS signal amplitude at various time lags, and allows for the exploration of dominant length scales in the propagation medium. We report the existence of a range where the structure function is linear with respect to time lag. This linear time segment could be considered as an analog to the inertial range in the context of neutral and plasma turbulence theory. Quantitatively, the slope of the structure function in the linear range is in good agreement with the scaling exponent determined from in situ measurements of the electrostatic potential at low altitude (E …

On the moments of probability distribution function of amplitude scintillation in the polar region

Authors

K Meziane,AM Hamza,PT Jayachandran

Journal

Journal of Geophysical Research: Space Physics

Published Date

2022/9

The distortions seen in the Global Navigation Satellite Systems radio signal caused by ionospheric irregularities in the polar region are examined through the lens of probability distributions of fluctuations in the recorded scintillation signals. The first four moments of the probability distribution function (PDF) of the amplitude scintillation are computed and analyzed for 106 events collected at Pond Inlet station [Magnetic Coordinates = (80.0°N, 2.6°E)]. As a starting point, the background variation level is investigated using similar computations carried out with about 400 30‐s window segments. The resulting distribution for the skewness (third moment) and the kurtosis (fourth moment) strongly indicate that the background fluctuations are nearly Gaussian; given the computed variances, the Rayleigh distribution hypothesis is ruled out. In the case where scintillation is present, we found that the skewness distribution …

A Bayesian Inference‐Based Empirical Model for Scintillation Indices for High‐Latitude

Authors

K Meziane,A Kashcheyev,PT Jayachandran,AM Hamza

Journal

Space Weather

Published Date

2021/6

Solar wind parameters, the solar radio flux index (F10.7), the Sun's declination and the SuperMAG Electrojet index are used to construct a Bayesian inference‐based empirical model for scintillation indices (S4 and σΦ) at high latitudes. For the present study, measurements from three Global Positioning System (GPS) L1 receivers located in the auroral zone, the cusp and in the polar cap are selected, respectively. The solar wind characteristics include the solar wind speed (VSW) and ram pressure (ρSW) as well as the Geocentric Solar Magnetospheric (GSM) By and the Bz components of the interplanetary magnetic field (IMF). Following a brief assessment on the independence of the variables (predictors), prior probabilities of occurrence in the case of a multinomial classification are constructed. Posterior‐probabilities are then deduced for any arbitrary set of predictors. We show that the model captures most …

On the latitude-dependence of the GPS phase variation index in the polar region

Authors

Karim Meziane,Anton Kashcheyev,Periyadan T Jayachandran,Abdelhaq M Hamza

Published Date

2020/10/12

It has long been established that the presence of irregularities in the ionosphere affects the propagation of radio waves, and in particular radio waves transmitted by GNSS satellites. Ionospheric scintillation is an important physical characteristic of radio wave signals propagating through the ionosphere. It is believed that a reverse backscattering analysis of the scintillating signals measured by GPS receivers on the ground may unveil some knowledge about the ionospheric irregularity structures causing the scattering in the first place and may in turn help understand the physical mechanisms causing the development of these irregularities. The Canadian High Arctic Ionospheric Network (CHAIN) GPS data are used to build probability functions for the phase variation index, which are best fit by the four-parameter Landau distribution. The fits reveal that the distribution scale-parameter value captures the known …

Solar cycle variations of GPS amplitude scintillation for the polar region

Authors

K Meziane,A Kashcheyev,S Patra,PT Jayachandran,AM Hamza

Journal

Space Weather

Published Date

2020/8

Global Positioning System (GPS) L1 amplitude data, obtained using the Canadian High Arctic Ionospheric Network (CHAIN) during the period 2008–2018, is used to study the seasonal and solar cycle dependence of high‐latitude amplitude scintillation. The occurrence of amplitude scintillation is predominantly confined to the 10–18 magnetic local time (MLT) and 72–87° Altitude‐Adjusted Corrected Geomagnetic (AACGM) sector and is a winter and equinoctial phenomenon. The occurrence of amplitude scintillation shows a clear seasonal and solar cycle dependence with a maximum value of 11% during the high solar activity early winter periods, and a secondary maximum in equinoctial months, and almost no occurrence during summer months. This pattern in occurrence suggests that amplitude scintillation is a phenomenon that is closely associated with the presence of patches and particle precipitation events.

See List of Professors in A. M. Hamza University(University of New Brunswick)

A. M. Hamza FAQs

What is A. M. Hamza's h-index at University of New Brunswick?

The h-index of A. M. Hamza has been 11 since 2020 and 17 in total.

What are A. M. Hamza's top articles?

The articles with the titles of

Two‐component phase scintillation spectra in the auroral region: Observations and model

Spectral characteristics of phase fluctuations at high latitude

Inferred Ionospheric irregularity scales from amplitude scintillation

Turbulence Signatures in High‐Latitude Ionospheric Scintillation

On the moments of probability distribution function of amplitude scintillation in the polar region

A Bayesian Inference‐Based Empirical Model for Scintillation Indices for High‐Latitude

On the latitude-dependence of the GPS phase variation index in the polar region

Solar cycle variations of GPS amplitude scintillation for the polar region

are the top articles of A. M. Hamza at University of New Brunswick.

What are A. M. Hamza's research interests?

The research interests of A. M. Hamza are: theoretical plasma physics

What is A. M. Hamza's total number of citations?

A. M. Hamza has 1,312 citations in total.

What are the co-authors of A. M. Hamza?

The co-authors of A. M. Hamza are Robert P Lin, James P McFadden, David L Mitchell, Patrick Newell, Ian Mann, Harald Kucharek.

    Co-Authors

    H-index: 105
    Robert P Lin

    Robert P Lin

    University of California, Berkeley

    H-index: 89
    James P McFadden

    James P McFadden

    University of California, Berkeley

    H-index: 76
    David L Mitchell

    David L Mitchell

    University of California, Berkeley

    H-index: 65
    Patrick Newell

    Patrick Newell

    Johns Hopkins University

    H-index: 55
    Ian Mann

    Ian Mann

    University of Alberta

    H-index: 49
    Harald Kucharek

    Harald Kucharek

    University of New Hampshire

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