Recent Submissions

Now showing 1 - 20 of 38
  • ItemOpen Access
    Quality improvements to the spectral data acquired from HF multi-static sounding system at the magnetic Equator
    (2023 SWOL Workshop, 2023-10) Vásquez, V.; Milla, M.; Kuyeng, Karim; Gonzales, J.; Scipión, Danny
    A network of HF radio beacons and receivers for ionospheric sounding has been operating in Peru since 2016. The purpose of this instrument is to measure the group delay, Doppler shift, power, and other parameters in order to estimate the regional plasma density as a function of space and time, this information is crucial for forecasting the occurrence of Spread-F. The HF radar used only one frequency for transmission and reception that generated interference between different transmitter stations in the analyzed spectrum. To improve the quality of the spectral data, changes were made to the operation of the radar. Spectral separation of the transmitted signals was carried out, followed by the implementation of an algorithm that extracts only the signals of interest from the measured spectrum, discarding the noisy areas. The procedure for the changes made to the HF system, along with comparisons of the final data, is shown in this work.
  • ItemOpen Access
    Preliminary AMISR-14 radar observations of F-region incoherent backscatter echoes at the Jicamarca Radio Observatory (JRO)
    (2022 CEDAR Workshop, 2022-06) Apaza, Joab; Kuyeng, Karim; Flores, Roberto; Milla, M.; Rodrigues, F. S.; Scipión, Danny
    A 14-panel Advanced Modular Incoherent Scatter Radar (AMISR-14) was installed at the Jicamarca Radio Observatory (IGP- JRO) in 2014. Because of its size, this radar was mainly used to observe coherent echoes such as those produced by the Equatorial Electrojet (EEJ) and Equatorial Spread F (ESF). However, the radar operation was intermittent until 2019 when repairs started to make the radar fully operational. Now, AMISR-14 runs regularly in parallel with the main Jicamarca radar in the JULIA (Jicamarca Unattended Long-term studies of the Ionosphere and Atmosphere) mode to monitor the Equatorial Spread F activity. More recently, we found that running these experiments with a more stable peak power, we have been able to detect not only coherently scatter (CS) signals but also what seems to be incoherently scattered (IS) echoes from the F-region ionosphere. In this poster, we will present some examples of the experiments we have been conducting with AMISR-14. More specifically, we will present and discuss examples of these interesting ISR-like echoes observed with AMISR-14 pointing in different directions along the E-W plane.
  • ItemOpen Access
    Clustering and data reduction algorithm applied to spectra measured with a multi-static HF sounding system in Peru
    (2023 CEDAR Workshop, 2023-06) Vásquez, V.; Milla, M.; Kuyeng, Karim; Gonzales, J.; Scipión, Danny
    The HF radar is a network of HF radio beacons and receivers for ionospheric sounding, and it has been operating in Peru since 2016. The purpose of this instrument is to measure the group delay, Doppler shift, power, and other parameters in order to estimate the regional plasma density as a function of space and time. This information is crucial for forecasting the occurrence of Spread-F. To improve the quality of the spectral data, two changes were made. The first one involved transmitting frequencies separated by 3.3 Hz in each transmission station, which allowed to spectrally separate and identify the signals coming from a given station, displacing the cross-talk in frequency but not eliminating it. Therefore, the second change was made, which corresponds to the development of an algorithm that extracts only the signals of interest from the measured spectrum. It is capable of detecting clusters of data in the spectra classifying them as coherent echoes, while noise sectors are discarded. The algorithm procedure and the comparisons of the spectra and final data are shown in this work.
  • ItemOpen Access
    Preliminary results of new operation mode JULIA Medium Power at JRO
    (2023 CEDAR Workshop, 2023-06) Kuyeng, Karim; Scipión, Danny; Condor, P.; Manay, E.; Milla, M.
    The main radar of the Jicamarca Radio Observatory (JRO), for several years, has operated with two main modes, the ISR mode with big transmitters (1.5 MW), operating around 1000 hours per year, to survey the ionosphere and obtain parameters such as drifts, densities and composition; and the JULIA mode with low power transmitters (20 kW), operating around 4000 hours per year, to measure mostly coherent echoes such as Equatorial Electrojet, Spread F and 150 km echoes to provide with a proxy of the behavior of the ionosphere. Starting in 2022, two new solid-state transmitters were installed at JRO, with peak power of 96 kW each, making it possible to not only detect coherent echoes but to be able to estimate zonal and vertical drifts in the ionosphere too. This new mode, called JULIA Medium Power (JULIA MP), is capable of measuring the same coherent echoes as the original JULIA but able to estimate zonal and vertical drifts up to 500 km. This work will present the preliminary results of this mode, comparisons of the coherent echoes obtained with JULIA and JULIA MP and finally show the quality of drifts we are getting with this medium power mode.
  • ItemOpen Access
    Estimation of spectral parameters from oblique Equatorial Electrojet echoes using a double skewed Gaussian model at JRO
    (2023 CEDAR Workshop, 2023) Flores, Roberto; Milla, M.; Kuyeng, Karim; Hysell, D.L.; Chau, J.L.
    Coherent echoes from the equatorial electrojet (EEJ) region are detected at the Jicamarca Radio Observatory (JRO) by using an array of 16 Yagi antennas with a main beam pointed obliquely to the west with an elevation of about 35 deg. The spectrum of these observations are composed of two types of EEJ echoes (Type I and Type II)[1] from which we can estimate their main spectral parameters such as Doppler shift and spectral width independently for each type. Previously, the method applied to obtain these parameters was a standard fitting approach based on a double Gaussian model. However, in some cases, the shape of the spectral measurements are not symmetric (resembling the shape of a skewed distribution). Based on simulations, we determined that the skewed shape of the oblique EEJ spectrum comes from the fact that the measured spectrum is the result of the sum of spectral contributions coming from different heights, with different Doppler shifts and spectral widths weighted by the antenna beam shape. The overall result is an asymmetric spectrum with a peak that does not coincide with the average Doppler shift. Thus in order to account for this effect, we have implemented a double skewed Gaussian distribution model to fit the oblique EEJ measurements and estimate their spectral parameters. In this work, we present the results obtained in the simulation showing the skewed shape of the spectrum. Based on our simulations, we have also proved that the shift of the skewed Gaussian model can be interpreted as the Doppler shift of the echoes. In addition, some examples of the new fitting procedure are shown in comparison with the classical Gaussian fitting where it can be seen the better agreement between the data and the double skewed Gaussian model.
  • ItemOpen Access
    Implementation of an Ionospheric Echoes Receiver using an SDR with GNU Radio to obtain vertical and oblique ionograms
    (2023 CEDAR Workshop, 2023-06) Tupac, Isaac; Milla, M.; Valladares, C.E.; Espinoza, J.C.; De la Jara, César; Arboleda, E.; Belleza, A.; Vila, N.; Scipión, Danny
    The Jicamarca Radio Observatory (JRO) operates a vertical incidence pulsed ionospheric radar (VIPIR) dedicated to probing the equatorial ionosphere. This high-resolution system runs 24/7 and complements the suite of observations performed at JRO. As the VIPIR ionosonde operates with a wide beam antenna and reflected signals are dispersed at distances far as 1500 km, we have designed, built, and installed four new VIPIR receivers dedicated to oblique sounding. These receivers increase and expand the system's field of view and enable unique measurements, yielding new scientific results. This poster describes the Ionospheric Echoes Receiver (IER) by listing its components and detailing the different parts of the hardware and software elements. The receivers use a USRP N200 by Ettus and an acquisition flowgraph implemented in GNU Radio Companion. In addition, we present the OOT (Out Of Tree block), which generates the demodulation signal and changes its frequency value each Inter Pulsed Period. We also show preliminary displays of the vertical and oblique ionograms acquired using the Jicamarca VIPIR and the new receivers.
  • ItemOpen Access
    Upgrade of Automatic Beam Switching (ABS) at Jicamarca Radio Observatory
    (Instituto Geofísico del Perú, 2021-06) Gonzales, L.; Espinoza, J.; Verástegui, J.; Ortecho, D.; Milla, Marco; Belleza, A.; Vila, N.
    Particular beam orientations are required for each experiment to study different atmospheric phenomena at the Jicamarca Radio Observatory (JRO), For an antenna array, this change can be done manually or remotely. JRO has had a beam steering system since 2005 for the remote operation. The remote operation is achieved using IP protocols and addresses associated with each antenna module and a web interface is used for the operation and supervision from the main building. The principle of the RF stage of the system is the phase shift due to change in the coaxial cable length between the source and the antennas in each antenna module. This poster summarizes the requirements of the system upgrade as well as the characteristics of the new electronic, mechanical, RF and interface design for each element of the automatic beam system used at JRO.
  • ItemOpen Access
    Spectra analysis in Faraday/Double Pulse experiment at Jicamarca Radio Observatory (JRO)
    (Instituto Geofísico del Perú, 2021-06) Flores, R.; Milla, Marco; Kuyeng, K.
    At the Geophysical Institute of Peru, specifically on its Jicamarca Radio Observatory (JRO) facility, there are different operation modes to obtain the main parameters of the equatorial ionosphere. One of these modes is the Faraday/Double Pulse which estimates plasma densities and electron/ion temperatures at the F region by pointing the antenna beam off perpendicular to the magnetic field. The data processing for this mode is currently done by using voltage analysis, but in order to obtain better results, spectra analysis has been implemented by using the radar data processing library developed at JRO called Signal Chain. This tool can analyze samples with the same lag and it is also possible to remove the DC clutter from them. Another advantage is that before making the incoherent integration over the spectra, these data can be stored and the outliers from samples with the same frequency can be removed. Comparisons between the different processing programs are shown on this work.
  • ItemOpen Access
    Reprocessing of data from Fabry-Perot interferometers (FPI) belonging to the IGP network of optical instruments
    (Instituto Geofísico del Perú, 2021-06) Barbaran Meza, J.; Rojas, R.; Navarro, L.; Veliz, Oscar; De la Jara, César; Milla, Marco
    IGP network of optical instruments consist of two types of imaging instrumentation: Fabry-Perot Interferometers (FPI) and All-Sky imagers (ASI). The FPI can obtain two dimensional interferograms that are used to study the dynamics of the upper atmosphere. Since the deployment of the first FPI in 1985 and up to the implementation of the FPI network in 2009, which was fully operational in 2011, a processing technique based on Fourier decomposition of the interferogram spectra has been used. An improvement of this technique has been released with a better representation and fitting scheme of the Airy function parameters needed for better estimation of the airglow neutral winds and temperatures. Given that the new processing technique has potentially the ability to generate better products, reprocessing of the IGPs optical data base is being evaluated. First, the two methods need to be compared. In this work we present an analysis of the two methods comparison, showing differences, advantages, and possible improvements to implement.
  • ItemOpen Access
    Radar imaging comparison methods
    (Instituto Geofísico del Perú, 2021-06) Yupanqui, Diego; Milla, Marco; Kuyeng, Karim; Ocaña, Eladio; Oré, Ernesto
    In this work, we are conducting a comparison of different methods to solve a one-dimensional aperture-synthesis radar imaging problem based on simulations. For this purpose, we are going to consider the geometry of the Jicamarca ionospheric radar. These methods are going to be applied to the generation of images of field-aligned plasma irregularities in the equatorial ionosphere, particularly, to the case of Spread-F phenomena. The methods used in the comparison goes from a direct Fourier inversion and a simple numerical integration, to more elaborated algorithms, such as, Capon’s method and Maximum entropy method. We are also going to include in the comparison, the compressed sensing technique using the Haar and dab4 basis, in this case, we are assuming that the brightness function of the spread-F echoes has a sparse representation. In the simulations of the radar measurements, we are considering Gaussian shape brightness functions. The different methods will be compared based on some metrics of the reconstructed images.
  • ItemOpen Access
    Modeling ionograms with deep neural networks: applications to foF2 forecasting
    (Instituto Geofísico del Perú, 2021-06) Aricoché, J.; Rojas, E.; Milla, Marco
    The ionosphere state parameters are of fundamental importance not only for radio communication but also for space weather. As most of the space phenomena, the dynamics are governed by nonlinear processes that make forecasts a challenging endeavor. We now have available enormous datasets and ubiquitous experimental sources that can help us finding the intricate regularities in these phenomena. In this work, we will focus on the forecasting of some parameters of the steady-state low latitude ionosphere. We used ionograms from Jicamarca Radio Observatory digisonde to train two neural networks. We produced forecasts of ionospheric parameters such as virtual heights and foF2 taking into consideration ionogram characteristics. These estimations were compared to the corresponding values obtained from the digisonde, the persistence model, and foF2 values obtained from the International reference ionosphere.
  • ItemOpen Access
    JRO digital receiver modernization using ADCs with high-speed JESD204B data interface and FPGAs
    (Instituto Geofísico del Perú, 2021-06) Verastegui, J.; Rojas, J.; Tupac, I.; Caceres, D.; Gonzales, L.
    The latest data acquisition system running at the Jicamarca Radio Observatory for the main radar has been used for more than five years now. Although there are no major inconveniences on the performance there have been some problems with internal interferences which are usually unpredictable and related to the PCB design, the noise floor can be different between channels too. So there are some chances of improvement developing a new approach. We propose a new design based on a high speed JESD204B data interface; the digital signal processing and custom acquisition logic will be implemented inside an FPGA capable of managing the JESD204B high-speed interface. This will give us the flexibility of implementing digital blocks inside the FPGA to improve the performance of the receivers, we will gain scalability to perform on a much higher bandwidth and the PCB will be very much simplified which will reduce the manufacturing costs, design time, and development time.
  • ItemOpen Access
    Exploration of machine learning tools developed for the study of space weather and its impact on position approximation in GNSS systems
    (Instituto Geofísico del Perú, 2021-06) Fajardo, G.; Pacheco, Edgardo E.
    The equatorial ionosphere has been extensively studied using purely physical models, however in recent years, with a large amount of data, it has been possible to improve these models using machine learning techniques. In this paper, we share the research results aimed to evaluate the influence of space weather parameters on GPS position approximation. We evaluated data from the Huancayo GPS station between 2016 and 2020 and we have taken into account the space weather data from the OMNI website, scintillation index (S4) and position data obtained from the GPS of the LISN network to perform our model. In addition, we use tropospheric conditions provided by the Geophysical Institute of Peru (IGP). The final result is a reliability matrix obtained with an XG Boost algorithm that will allow us to evaluate if a GPS signal given the conditions is indeed reliable or not.
  • ItemOpen Access
    Diurnal and semidiurnal tides in the Mesosphere and Lower Thermosphere over the central coast of Peru
    (Instituto Geofísico del Perú, 2021-06) Suclupe, J.; Milla, Marco; He, M.; Chau, J. L.
    It has been over a year since measurements of mesosphere and lower thermosphere (MLT) winds have been obtained with the SIMONe Peru radar. This modern multistatic specular meteor radar, placed on the central coast of Peru, has its transmitter located at the Jicamarca Radio Observatory (11.95° S, 76.87° W, dip angle 1°). This work will show some results of the climatology of diurnal and semidiurnal tides obtained from the analysis of zonal and meridional mean winds that have been estimated at heights between 80-100 km using one year of data (Nov 2019 - Oct 2020). The monthly and seasonal variation of tide amplitudes will be described. From the results we have seen that diurnal tides are more intense than semidiurnal tides, which is typical at low latitudes and that diurnal tide is more intense in August and September. These and others results will also be described in this work.
  • ItemOpen Access
    Development of JROMAG-M103 magnetometer for geomagnetism studies in Peru
    (Instituto Geofísico del Perú, 2021-06) Rojas, Ricardo; Veliz, Oscar
    Since 2007 a three-axis fluxgate magnetometer has been in development and under continuous improvement at Jicamarca Radio Observatory of the Geophysical Institute of Peru. It is based on the Fluxgate Mag-03 magnetic detector by Bartington Instruments. The JROMAG-M103 was developed to meet specific requirements of sensitivity, resolution, robustness, among others. This magnetometer, called JROMAG-M103, is being used in several geomagnetic monitoring networks, from different research institutions in South America. This poster presents the design aspects and technical specifications of the magnetometer and introduces further improvements that will be included in future versions.
  • ItemOpen Access
    Crowdsourcing ionogram scaling: a citizen science project
    (Universidad Peruana de Ciencias Aplicadas, 2021-06) Ccanto, Stephany; Vilchez, Amanda; Girón, Marie; Strobbe, Alessandro; Moyna, Shermely; Rojas, Enrique
    Citizen science (CS) is defined as a form of research collaboration or data gathering performed by non-experts or untrained individuals. CS projects benefit scientists by providing resources for data processing, gathering, pattern recognition, etc. On the other hand, for volunteers, CS represents the democratization of science, and the opportunity to be involved in local issues as well as a strong public education aspect. In this work, we will use to create a CS project using data from Jicamarca Radio Observatory’s ionosonde. Participants will use a built-in draw tool to identify the ordinary and extraordinary lines from an ionogram power image, which then can be used for parameter estimation. Furthermore, we will describe our plans for data management and public engagement. We hope this work will motivate our community to use CS projects both as a scientific and an outreach approach.
  • ItemOpen Access
    SIMONe Peru: deployment and operations
    (Instituto Geofísico del Perú, 2020-06) Suclupe, J.; Kuyeng, K.; Milla, Marco; Chau, J.L.; Urco, M.; Pfeffer, N.; Clahsen, M.; Vierinen, J.; Erickson, P.
    SIMONe Peru is a modern multistatic specular meteor radar which allows measuring winds in the mesosphere and lower thermosphere (MLT) between 70 and 110 km in altitude. Its main objective is to study the atmospheric dynamic in this region. Moreover, the system provides a higher number of detections compared to other systems and gives good statistics from detections in this region. This system started operations on september 2019 in the central coast of Peru. This work presents a general outline of the SIMONe Peru system, as well as the some preliminary results that allow us to operate and monitor it.
  • ItemOpen Access
    Exploring the correlation between ionospheric scintillation and GNSS positioning error near the magnetic equator using machine learning techniques
    (Instituto Geofísico del Perú, 2020-06) Fajardo, G.; Pacheco, Edgardo E.
    Ionospheric scintillations are a common phenomenon in the equatorial ionosphere. This phenomenon directly affects the position estimated by GNSS receivers degrading the quality of the radio signals; however, the quantification of the positioning error contributed by the ionosphere over the Peruvian sector has not been studied in detail. In this work, algorithms are being implemented that will allow us to identify and classify amplitude scintillation (S4) levels, we have worked with data from the Huancayo Observatory for the period December 2016-February 2017 obtained from LISN, this data has been plotted to analyze the spatial and temporal occurrence, and to analyze the occurrence of S4 as a function of other space weather variables obtained from OMNI2. The machine learning algorithms were decision tree, Support Vector Machine (SVM), Neuronal Network (NN). Decision tree was implemented as a filtering method, support vector machine for clustering and neuronal network to generate time series in forecasting. This paper shows the initial part of an investigation that aims to correlate qualitatively and quantitatively the occurrence of amplitude scintillations (S4) with errors in the position estimation of GNSS receivers, once the correlation between S4 and position error has been quantified, it may be possible to predict the error by predicting S4.
  • ItemOpen Access
    Initial design of a GNU radio interface for the new version of the Jicamarca Acquisition Radar System (JARS 2.0)
    (Instituto Geofísico del Perú, 2020-06) Tupac, Isaac; Rojas, John; Verástegui, Joaquín; Espinoza, Juan Carlos; Milla, Marco
    In this poster the initial design of a new software interface to control the novel ethernet based radar acquisition system JARS 2.0 of the Jicamarca Radio Observatory is presented. This interface will be implemented using the open-source software development toolkit GNU Radio; which besides controlling the JARS 2.0, it will obtain the acquired data for its further processing. The aim of the project, although in its development stage, will be to use the benefits of the GNU Radio to process, plot and even save the data in an standard way.
  • ItemOpen Access
    Using JULIA long dataset to find preconditioning evidence of ESF in bottom-type layers
    (Instituto Geofísico del Perú, 2008) Pinedo, H.; Chau Chong Shing, Jorge Luis; Hysell, D.
    Recently Hysell et al. [2005] has suggested that the periodic structuring observed in the bottomtype (BT) scattering layers might be used to determine the occurrence or not of full-blown equatorial spread F (ESF) on a given day. The seed or precursor waves may be generated by a collisional shear instability. Preliminary observations at Jicamarca and AL TAIR have shown that such structures present wavelengths of the order of tens or hundreds of kilometers. At Jicamarca periodic structures have been observed using in-beam radar imaging techniques, however such observations are limited to few days in the last five years. On the other hand, routine observations using the JULIA system at Jicamarca have been done since 1996 on approximately 100 days per year on average, using interferometric and dual-beam observations with very narrow beams. Since the bottom-type irregularities drift ata relatively constant speed in the westward direction, using the JULIA narrow beams (~1o), the spatial periodicities might be observed as temporal periodicities in typical range-time intensity maps. In this initial work we present the statistics of the observed bottom-type periodicities and the occurrence of ESF plumes as detected with the JULIA system for years 2006-2008. Besides we presenta time occurrence statistics of a weak bottom-type layer that took place previously to bottom-type layers.
    Palabras clave:RadarAtmospherePlasma