Utjecaj Sunca na Ionosferu I propagaciju radijskih valova

undergraduate thesis

• Title (english): The influence of the Sun on the Ionosphere and the propagation of radio waves
• Author: Kristina Vrabec
• Mentor: Krešimir Malarić (mentor)
• Mentor: Igor Štambuk (komentor)
• Committee member: Ivica Smojver (predsjednik povjerenstva)
• Committee member: Krešimir Malarić (član povjerenstva)
• Committee member: Igor Štambuk (član povjerenstva)
• Granter: University of Zagreb; (Croatian Defence Academy "Dr. Franjo Tuđman"); Zagreb
• Defense date and country: 2023-07-05, Croatia
• Scientific / art field, discipline and subdiscipline: SOCIAL SCIENCES; Security and Defense Science
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Geophysics

Abstract

Sunce konstantno emitira radijaciju i ionizirane čestice putem solarnog vjetra, a može doći i do
naglog povećanja emisije tijekom fenomena kao što su solarna baklja i koronalni izbačaji mase.
Sunčeva aktivnost prati 11-godišnji ciklus te je u direktnoj korelaciji s brojem Sunčevih pjega.
Povećana radijacija sa Sunca uzrokuje intenzivniju ionizaciju u slojevima ionosfere te pridonosi
povećanju njihove gustoće. U radu je opisan utjecaj Sunca na ionosferu i VF radijsku
komunikaciju koja za propagaciju valova koristi refleksiju od ionosfere. Pomoću programa
VOACAP provedena je analiza kretanja maksimalne upotrebljive frekvencije (MUF) tijekom
različitih uvjeta Sunčevog djelovanja, odnosno tijekom izmjene dana i noći, solarnog
maksimuma i solarnog minimuma te izmjene godišnjih doba (odnos ljeto-zima).

Abstract (english)

The Sun continuously emits radiation and ionized particles via the solar wind, also rapid
increases in the level of emission can occur during events such as solar flares and coronal mass
ejections. The Sun's activity follows an 11-year cycle, which is in direct correlation with the
number of Sunspots. Increased solar radiation causes more intense ionization of the ionospheric
layers and contributes to the increase in their density. This paper depicts the influence of the Sun
on the ionosphere and HF radio communication, which uses the reflection of the ionosphere for
radio wave propagation. Using the VOACAP program, an analysis of the movement of the
maximum usable frequency (MUF) was carried out for different conditions of solar activity, that
is, for the alternation of day and night, solar maximum and solar minimum, and the alternation of
seasons (summer-winter alternation).

• Keywords: Sunčev ciklus; Sunčeve pjege; ionosfera; slojevi ionosfere; VF propagacija; maksimalna upotrebljiva frekvencija (MUF); VOACAP
• Keywords (english): Sunspots; Solar cycle; ionosphere; ionospheric layers; HF propagation; maximum usable frequency (MUF); VOACAP
• Language: croatian
• URN:NBN: urn:nbn:hr:249:461876
• Study programme: Title: Military Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica inženjer/inženjerka vojnog inženjerstva (sveučilišni/a prvostupnik/ prvostupnica inženjer/inženjerka vojnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2024-01-15 11:05:22