{"id":14514,"date":"2025-06-07T16:28:32","date_gmt":"2025-06-07T10:58:32","guid":{"rendered":"https:\/\/ibexaviation.com\/pilot-training\/?p=14514"},"modified":"2026-07-26T09:52:46","modified_gmt":"2026-07-26T04:22:46","slug":"modullation-of-radio-wave","status":"publish","type":"post","link":"https:\/\/ibexaviation.com\/pilot-training\/modullation-of-radio-wave\/","title":{"rendered":"Modullation of Radio Wave"},"content":{"rendered":"<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-1.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<h2>Modulation &#8211; Transmission of Intelligence using Radio Waves<\/h2>\n<p>Modulation is the process of changing a property of a high-frequency carrier wave according to the information (voice, music, or data) to be transmitted. It allows signals to travel long distances efficiently without interference. The main types of modulation are Keyed Modulation, Amplitude Modulation (AM), Frequency Modulation (FM), Phase Modulation and Pulse Modulation.\n<\/p>\n<h3>Modulation<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-2.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Modulation is the process of superimposing intelligence (voice or data) onto a carrier wave.<\/li>\n<li>A carrier wave is a high-frequency wave containing high energy.<\/li>\n<li>The amplitude and frequency of an unmodulated carrier wave remain constant.<\/li>\n<li>A signal wave is a low-energy wave that carries voice or data information.<\/li>\n<\/ul>\n<h3>Keyed Modulation<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-3.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Keyed modulation is the simplest form of modulation.<\/li>\n<li>Information is transmitted by switching the carrier wave on and off.<\/li>\n<li>Morse code is a common example of keyed modulation.<\/li>\n<\/ul>\n<h3>Amplitude Modulation (AM)<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-4.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Amplitude Modulation (AM) changes the amplitude of the carrier wave.<\/li>\n<li>The amplitude of the signal wave controls the amplitude of the carrier wave.<\/li>\n<\/ul>\n<h3>Frequency Modulation (FM)<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-5.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Frequency Modulation (FM) changes the frequency of the carrier wave.<\/li>\n<li>The amplitude of the signal wave is used to vary the carrier frequency.<\/li>\n<li>FM requires a wider bandwidth than AM.<\/li>\n<\/ul>\n<h3>FM and AM Transmitters and Receivers<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-6.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>FM transmitters are simpler and consume less power than AM transmitters.<\/li>\n<li>FM receivers are more complex than AM receivers.<\/li>\n<li>FM provides better signal clarity because it is less affected by static noise.<\/li>\n<\/ul>\n<h3>Analogue Phase Modulation<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-7.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Phase Modulation (PM) changes the phase of the carrier wave.<\/li>\n<li>Phase modulation may be analogue or digital.<\/li>\n<li>Analogue phase modulation varies the phase by making short-term frequency changes.<\/li>\n<li>The amplitude of the signal wave controls the phase of the carrier.<\/li>\n<\/ul>\n<h3>Digital Phase Modulation<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-8.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Digital phase modulation is also known as <strong>Phase Shift Keying (PSK)<\/strong>.<\/li>\n<li>It changes the phase of the carrier using binary data.<\/li>\n<li>Binary values represent different phase shifts within the 360\u00b0 cycle.<\/li>\n<li>Digital phase modulation provides superior noise immunity and reduces fading.<\/li>\n<li>GPS and MLS use Phase Shift Keying (PSK) technology.<\/li>\n<\/ul>\n<h3>Pulse Modulation<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-9.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Pulse modulation transmits the carrier wave in short pulses.<\/li>\n<li>Radar and data link systems commonly use pulse modulation.<\/li>\n<li>The transmitted pulses are accurately timed and of very short duration.<\/li>\n<li>Pulse duration is measured in microseconds (\u00b5s).<\/li>\n<li>Pulse intervals are typically measured in milliseconds (ms).<\/li>\n<\/ul>\n<h2>Side Bands in Modulated Signal Wave<\/h2>\n<h3>Heterodyning<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-10.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Heterodyning is the process of combining the carrier wave with the signal wave during modulation.<\/li>\n<li>Heterodyning produces two sidebands.<\/li>\n<li>One sideband is the <strong>sum<\/strong> of the carrier and signal frequencies.<\/li>\n<li>The other sideband is the <strong>difference<\/strong> between the carrier and signal frequencies.<\/li>\n<li>Bandwidth is the range of frequencies occupied by the modulated signal.<\/li>\n<\/ul>\n<h3>Depth of Modulation<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-11.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Depth of Modulation (DDM) indicates the quality or clarity of modulation.<\/li>\n<li>It is the ratio between the amplitudes of the modulated and unmodulated carrier wave.<\/li>\n<li>It is calculated using the maximum and minimum amplitudes.<\/li>\n<\/ul>\n<p><strong>DDM = (Maximum Amplitude \u2212 Minimum Amplitude) \u00f7 (Maximum Amplitude + Minimum Amplitude) \u00d7 100<\/strong><\/p>\n<h3>Double Sideband (DSB)<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-12.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Bandwidth is the frequency range occupied by a modulated signal.<\/li>\n<li>Double Sideband (DSB) modulation retains both upper and lower sidebands.<\/li>\n<li>The audio signal power is distributed equally between the two sidebands.<\/li>\n<\/ul>\n<h3>Single Sideband (SSB)<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-13.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Single Sideband (SSB) suppresses the lower sideband.<\/li>\n<li>The signal power is concentrated in the upper sideband.<\/li>\n<li>SSB offers several advantages over DSB:<\/li>\n<ul>\n<li>Reduced bandwidth requirements.<\/li>\n<li>More communication channels can be accommodated.<\/li>\n<li>Lower interference.<\/li>\n<li>Higher transmission efficiency.<\/li>\n<\/ul>\n<\/ul>\n<h2>Doppler Effect &#8211; Frequency Shift during Transmission<\/h2>\n<h3>Doppler Principle<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-14.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>The Doppler Principle is used to measure the relative speed of a moving object.<\/li>\n<li>Airborne Doppler radar and Doppler VOR use this principle.<\/li>\n<li>Doppler Shift is the change in received frequency caused by relative motion.<\/li>\n<li>It depends on the relative velocity between the transmitter and receiver.<\/li>\n<li>Relative velocity is determined by measuring frequency or phase differences.<\/li>\n<\/ul>\n<h3>Doppler Shift Formula<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-15.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<p><strong>Doppler Shift = (Transmitted Frequency \u00d7 Relative Velocity) \u00f7 Speed of Light<\/strong><\/p>\n<h3>Emission Designators<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-16.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>Emission designators identify the characteristics of transmitted radio signals.<\/li>\n<li>Different radio navigation aids use different emission designators.<\/li>\n<\/ul>\n<h3>Parts of Emission Designators<\/h3>\n<p> <img decoding=\"async\" src=\"https:\/\/ibexaviation.com\/page-show\/radio-navigation\/r3-modullation-of-radio-waves-17.jpg\" alt=\"\" loading=\"lazy\"\/><\/p>\n<ul>\n<li>An emission designator consists of three parts.<\/li>\n<li>The first part indicates the type of carrier wave modulation.<\/li>\n<li>The second part identifies the nature of the signal modulating the carrier.<\/li>\n<li>The third part specifies the type of information being transmitted.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Modulation &#8211; Transmission of Intelligence using Radio Waves Modulation is the process of changing a property of a high-frequency carrier wave according to the information (voice, music, or data) to be transmitted. It allows signals to travel long distances efficiently without interference. The main types of modulation are Keyed Modulation, Amplitude Modulation (AM), Frequency Modulation (FM), Phase Modulation and Pulse Modulation. Modulation Modulation is the process of superimposing intelligence (voice or data) onto a carrier wave. A carrier wave is a high-frequency wave containing high energy. The amplitude and frequency&hellip;<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"disable_featured_image":false,"footnotes":""},"categories":[326],"tags":[],"class_list":["post-14514","post","type-post","status-publish","format-standard","hentry","category-cpl-atpl-radio-navigation"],"_links":{"self":[{"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/posts\/14514","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/comments?post=14514"}],"version-history":[{"count":2,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/posts\/14514\/revisions"}],"predecessor-version":[{"id":16596,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/posts\/14514\/revisions\/16596"}],"wp:attachment":[{"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/media?parent=14514"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/categories?post=14514"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ibexaviation.com\/pilot-training\/wp-json\/wp\/v2\/tags?post=14514"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}