FINAL YEAR PROJECT REPORT:

NAME: FEMI MICHAEL ADELEKE

DEGREE: B.Eng. TELECOMMUNICATION ENGINEERING

COURSE CODE: ICE

YEAR: FINAL

PROJECT TITLE: DEVELOPMENT OF A SUDDEN IONOSPHERIC DISTURBANCE MONITOR:

ABSTRACT

ACKNOWLEDGEMENTFirst of all I would like to thank my project supervisor Prof. Patrick McNally for helping me get started and his support throughout the project, and would also like to thank the Technical team for their support in purchasing the necessary components required for my project. Another person that deserves greatly to be acknowledged is Robert Clare, an employee in DCU for offering expertise with PCB building and mainly his good advice.

I would also like to thank everyone working in the NanoMaterial Processing Lab SB07 for their constant support , they were very helpful when i experienced any challenges. In actual fact they also supported me in my choice of building the receiver Antenna, Big Antenna or Small Antenna for this project which turns out to be the correct one.

Finally i would like to thank my family and friends for putting up with my constant moaning about the project and supporting me through difficult times.

DECLARATION

I hereby declare that, except where otherwise indicated this document is entirely my own work and has not been submitted in whole or in part to any other university

Signed:...................................... Date:.............................

LIST OF ABBREVIATIONSSID Sudden Ionospheric Disturbance

SSIDMON Solar Sudden Ionospheric Disturbance Monitor

CMEs Coronal Mass Ejections

EUV Extreme Ultra Violent waves

ELF Extremely Low Frequency

SLF Super Low Frequency

ULF Ultra Low Frequency

VLF Very Low Frequency

LF Low Frequency

MF Medium Frequency

HF High Frequency

VHF Very High Frequency

UHF Ultra High Freqeuncy

SHF Super High Frequency

EHF Extremely High Frequency

TABLE OF CONTENTS

CHAPTER 1INTRODUCTIONOverview: Solar Flares

For my project, I am required to build a SID receiver, and antenna which will monitor the effects of solar flares on the earth’s ionosphere, but before i continue, i would like to give an overview on sum of the background readings involved in this project, i.e. what is solar flares, where is Ionosphere, different regions in ionosphere, where they were located, how about VLF a very low frequency station and finally the SID monitor itself what it does. So therefore what are Solar flares? They are burst energy that affects Earth’s ionospheric density, research proves that it is unknown how they affect the ionosphere but hence scientist can tract their effect when they occur. This project is in two fold, 1.to construct an antenna that attaches to a SID (Sudden Ionospheric Disturbance) monitor to begin data collection for future research and to build a SID receiver which monitors the effects of Solar flares day and in night time. This monitor measures ionospheric changes by tracking changes in very low frequency radiowaves VLF. Using previous research studies, it is hypothesized that Solar flares will have a distinguishable impact within SID data.

Solar activity can cause extreme disaster in our high tech society. The radiationand plasma from solar activity can destroy million dollar satellites, explode gas and oilpipelines, and disrupt the Earth’s magnetic fields. Solar activity can also cause large scaleblackouts, leaving major areas without power for days. Disrupted bird migration, GPSmalfunction, electrified telephone wires, and auroras are all effects of magnetic storms,which are caused by solar activity.

Solar flares are the most violent form of solar activity. They are the suddenrelease of magnetic energy, causing an increase in radiation given off across thespectrum, including extreme ultraviolet waves. The figure below picture solar flare occurrence.

Figure 1:

When this occur two poisonous energy are released into the atmosphere, X-rays, or Extreme ultra-violent rays EUV , they both travel at the speed of light, taking only 8.3 minutes to reach us here on earth. The second energy release is through the impact of matter from the sun. Plasma, or matter in a state where electron wonder around freely among the nuclei of the atoms, they are called CMEs, coronal mass ejections, this is the most deadly of all, it flows from the sun at a speed of over two million kilometres per hour, thus taking about 72 hours before reaching us on earth. The main effect of this radiation is evident in ionospheric changes.

Ionosphere

What is ionosphere and where is it located. It is defined as the layer of the Earth's atmosphere that is ionized by solar and cosmic radiation. It lies 75-1000 km (46-621 miles) above the Earth. Because of the high energy from the Sun, the atoms in this area have been “ionized,” and are therefore positively charged. The ionized electrons behave as free particles. The Sun's upper atmosphere, the corona is very hot and produces a constant stream of plasma and UV and X-rays that flow out from the Sun and affect, or ionize, the Earth's ionosphere.

During the night, without the presence of the sun, cosmic rays ionize the ionosphere unlike day time where the sun ionise the ionosphere which make ionosphere less charge at night time . Ionosphere is more important to us unlike other atmosphere, why? Because it influences radio propagation to distant places on Earth.

The ionosphere is composed of three main parts, namely the D, E, and F regions. The electron density is highest in the upper, or F region. The F region exists during both daytime and nighttime. During the day it is ionized by solar radiation, during the night where there is no presence of the sun it is ionise by cosmic rays. The D region disappears during the night hence making the E region more dense and weekend.

Figure 2: The Earth’s atmosphere and ionosphere

During the night time Figure 3 below, right side, the ionosphere has only the F and E layers. A VLF wave from a transmitter reflects off the ions in the E layer and bounces back.

Daytime Night time

Figure 3:

And during the daytime left side, the Sun’s X-ray and UV light increase the ionization of the ionosphere, creating the D and enhancing the E layers, and splitting the F region into 2 layers. The D layer is normally not dense enough to reflect the radio waves. But the E layer is, so the VLF signals go through the D layer, bounce off the E layer from figure 3 above and go back down through the D layer to the ground. During this process the signals lose energy as they penetrate through the D layer and hence radios pick up weaker signals from the transmitter during the day. When a solar flare occurs, even the D layer becomes ionized, hence allowing signals to bounce off it.

Very Low Frequency (VLF)

For my project, I will use a VLF a very low frequency which correspond to the frequency between 3 kHz to 30 kHz to track down the effect of solar flares on Earth’s ionosphere this is done by monitoring the . VLF waves are used for time signals and radio navigation beacons, i.e. Russian hyperbolic radio navigation system. The most amazing thing about a VLF is that they can penetrate water to a depth of 10 feets, which is why the military are using it to communicate with submarines close to the surface. Hence the list of VLF transmitters suitable for my SID monitoring is in the Appendix.

Figure 4:

Station Overview:

For this project, the station consists of an Antenna, VLF receiver board and a SID monitoring software.

Figure 5:

ANTENNA

For my project, the antenna does not need to be tuned, it should consists of 40 to 50 turns of copper wire wounded around a specific frame

The following items are necesary to build the antenna:

One frame 70x100cm (27-½ x 39-¼″). Pine corner molding 22x22mm (7⁄8"x7⁄8″) TNC-Female Bulkhead 50Ω Connector Magnet wire (solid copper wire with varnish insulation) Wood glue For the cable: RG-58 Coax cable (length as needed) and two male 50Ω TNC connectors.

A SID monitor is a device created to study the ionospheric responses to the Sun. Itdoes this by tracking very low frequency waves. Very low frequency waves areappropriate for this use because they are constantly being transmitted and can be receivednearly anywhere on Earth. SID monitors are tracking VLF signals from 23 stations in 10countries. The SID network works on a series of receivers and transmitters. Eachtransmitter has its own frequency, and each receiver is tuned to pick up one of thesefrequencies. This way, the data is collected globally, the sunset/sunrise effects on thetransmitter and receiver are equal, and there is a constant collecting of data, even whenone transmitter is under maintenance. Currently, SID data is being analyzed for itsinformation on ionospheric response to sunrise and sunset effects. Lightning alsoproduces an ionospheric response detectable within SID data (13). The only type of solarstorm shown to have any impact on the ionosphere is solar flares (13).Coronal mass ejections, or CMEs, are another type of solar storm. They occurwhen there is a sudden increase in the radiation given off by the Sun, such as the increasegiven off by a flare. The radiation causes plasma from the corona, or outer atmosphere ofthe Sun, to be forced out in the direction of the energy. These plasma masses carry theirown magnetic field and are defined as CMEs. They move at speeds ranging from 900 to1400 kilometers per second, reaching the Earth anywhere from 12 hours to 6 days aftertheir eruption. CMEs are manually detected within coronagraph images. A coronagraphis a telescope that places a blocking disk in front of the solar disk in order to see andstudy the corona. A common source for coronagraphic images is the Large Angle andSpectrometric Coronagraph (LASCO) instrument onboard the Solar and Heliospheric6Observatory (SOHO) spacecraft. To date, SID monitors have never been used fordetecting CMEs (13).The purpose of this study was to determine if earthbound CMEs have a significantimpact on the lower ionosphere that is detectable within SID data. Earthbound CMEswere identified by the appearance of a width of 360° in the coronagraph images provided

by the LASCO instrument on the SOHO spacecraft (14). The SID data from 2-3 daysafter the appearance of the halo CME, the approximate arrival time for a CME, wascompared to data where there was no solar activity to identify a change caused by aCME. Additionally, this study included the construction of an antenna to attach to a SIDmonitor to start collecting data for future research.