{"id":2863,"date":"2024-08-14T19:11:20","date_gmt":"2024-08-14T13:41:20","guid":{"rendered":"https:\/\/study.madeeasy.in\/?p=2863"},"modified":"2025-07-16T15:05:17","modified_gmt":"2025-07-16T09:35:17","slug":"data-transmission-schemes","status":"publish","type":"post","link":"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes","title":{"rendered":"Data Transmission Schemes"},"content":{"rendered":"<p style=\"text-align: justify;\">As we have studied earlier about the base band pulse transmission, we have seen that the output of a PCM code system is a string of 1\u2019s and 0\u2019s. If they are to be transmitted over copper wires, they can be directly transmitted as appropriate voltage levels using line code. But if they are transmitted through space using antenna, some form of modulation has to be used.<\/p>\n<p style=\"text-align: justify;\">In any event, the modulation process makes the data transmission schemes possible involves switching (keying) the amplitude, frequency or phase of sinusoidal carrier in some fashion in accordance with incoming data. Thus, there are three basic signalling schemes and they are known as amplitude shift keying (ASK), frequency shift keying (FSK) and phase shift keying (PSK) and this is called bandpass transmission of signals.<\/p>\n<p style=\"text-align: justify;\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2864 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/bandpass-modulation.jpg\" alt=\"Bandpass Modulation\" width=\"572\" height=\"193\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/bandpass-modulation.jpg 572w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/bandpass-modulation-300x101.jpg 300w\" sizes=\"auto, (max-width: 572px) 100vw, 572px\" \/><\/p>\n<p style=\"text-align: justify;\">Process of bandpass transmission can be explained from Figure- (b) as follows. Message source emits symbols m<sub>1<\/sub>, m<sub>2<\/sub>, \u22c5 \u22c5 \u22c5 m<sub>m<\/sub> and let their probability of transmission is p<sub>1<\/sub>, p<sub>2<\/sub>, \u22c5 \u22c5 \u22c5 p<sub>m<\/sub>. If not specified then we can assume that all symbols are equiprobable in transmission. Then probability of transmission of any symbol is<\/p>\n<p style=\"text-align: center;\">p(m<sub>i<\/sub>) = 1\/m for i = 1, 2,&#8230;,m.<\/p>\n<p style=\"text-align: justify;\">Then modulator takes the message source output mi and codes it into distinct signals s<sub>i<\/sub>(t) suitable for transmission<br \/>\nover the channel. The duration of s<sub>i<\/sub>(t) is same as that of symbol m<sub>i<\/sub> i.e. T seconds. As s<sub>i<\/sub>(t) is of a finite duration, so its energy can be given as<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2865 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/modulator.jpg\" alt=\"Modulator\" width=\"107\" height=\"53\" \/><\/p>\n<p style=\"text-align: justify;\"><strong>Let communication channel has two characteristics:<\/strong><\/p>\n<ul style=\"text-align: justify;\">\n<li>It is linear and its bandwidth is wide enough to accommodate transmission of signal s<sub>i<\/sub> (t) with negligible or no distortion.<\/li>\n<li>Channel noise w(t) is sample function of a zero mean white Gaussian noise process. Hence, received signal can be expressed as<\/li>\n<\/ul>\n<p style=\"text-align: justify;\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2866 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/gaussian-noise.jpg\" alt=\"Gaussian Noise\" width=\"307\" height=\"43\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/gaussian-noise.jpg 307w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/gaussian-noise-300x42.jpg 300w\" sizes=\"auto, (max-width: 307px) 100vw, 307px\" \/><\/p>\n<p style=\"text-align: justify;\">The main task of receiver is to observe the signal s<sub>i<\/sub>(t) for \u2018T\u2019 duration and estimate the message symbol m<sub>i<\/sub> from it. But this estimation is complex in the way that value of s<sub>i<\/sub>(t) may change due to presence of channel noise and receiver will make occasional errors. So, the receiver is to be designed to minimize probability of error, defined as<\/p>\n<p style=\"text-align: justify;\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2867 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/probability.jpg\" alt=\"Probability\" width=\"668\" height=\"110\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/probability.jpg 668w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/probability-300x49.jpg 300w\" sizes=\"auto, (max-width: 668px) 100vw, 668px\" \/><\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_79_1 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-light-blue ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#Digital-Modulation-Schemes\" >Digital Modulation Schemes<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#Quadrature-Amplitude-Modulation\" >Quadrature Amplitude Modulation<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#Signal-Space-Representation-of-QAM\" >Signal Space Representation of QAM<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#Differential-Phase-Shift-Keying-DPSK\" >Differential Phase Shift Keying (DPSK)<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#DPSK-Transmitter\" >DPSK Transmitter<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#DPSK-Receiver\" >DPSK Receiver<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#Minimum-Shift-KeyingMSK\" >Minimum Shift Keying(MSK)<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#Two-important-differences-between-QPSK-and-MSK\" >Two important differences between QPSK and MSK<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#Bandwidth-of-MSK\" >Bandwidth of MSK<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#Advantages-of-MSK\" >Advantages of MSK<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.madeeasy.in\/study\/ec\/communication-systems\/data-transmission-schemes\/#Disadvantages-of-MSK\" >Disadvantages of MSK<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h3 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Digital-Modulation-Schemes\"><\/span>Digital Modulation Schemes<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p style=\"text-align: justify;\"><strong>Basically, there are two types of digital modulation schemes:<\/strong><\/p>\n<p style=\"text-align: justify;\"><strong>Binary schemes:<\/strong> In Binary schemes: this, we send one of the two possible signals during each signalling interval of duration T<sub>b<\/sub>. Examples are: ASK, FSK and PSK.<br \/>\n<strong>M-ary schemes:<\/strong> In this, we M-ary schemes: send one of the M-possible signals during each signalling interval of duration T. Number of possible signals, M = 2<sup>n<\/sup> and the signalling interval T = nT<sub>b<\/sub>. Each of the M signals is called a symbol, which consists of n = log<sub>2<\/sub>M bits.<br \/>\nExample are: M-ary PSK, MSK, QAM, QPSK etc. These techniques are discussed one by one in following sections.<\/p>\n<h3 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Quadrature-Amplitude-Modulation\"><\/span>Quadrature Amplitude Modulation<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p style=\"text-align: justify;\">In PSK technique, one symbol is distinguished from other in phase, but all the symbols are same in amplitude in M-ary PSK. As we know that, the ability of receiver to distinguish between one signal vector from another depends on distance between vector end points. Hence noise immunity will improve if signals differs not only in phase but also in amplitude. Such a system is called as amplitude and phase shift keying system. It is also known as quadrature amplitude modulation. QAM is a form of digital modulation similar to PSK except the digital information is in both amplitude and phase of transmitted carrier.<\/p>\n<h4 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Signal-Space-Representation-of-QAM\"><\/span>Signal Space Representation of QAM<span class=\"ez-toc-section-end\"><\/span><\/h4>\n<p style=\"text-align: justify;\">We want to transmit a symbol consisting of 4-bits. This means that N = 4 and there are 2<sup>4<\/sup> = 16 possible symbols. Hence the QASK system, we should be able to generate 16 different distinguishable signals. A possible geometric representation of 16 symbols is shown in figure. Each signal point is equally distant from its nearest neighbours.<\/p>\n<p style=\"text-align: justify;\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2871 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/qam.jpg\" alt=\"QAM\" width=\"333\" height=\"297\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/qam.jpg 333w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/qam-300x268.jpg 300w\" sizes=\"auto, (max-width: 333px) 100vw, 333px\" \/><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2869 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/signal-space-representation.jpg\" alt=\"Signal Space Representation\" width=\"508\" height=\"318\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/signal-space-representation.jpg 508w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/signal-space-representation-300x188.jpg 300w\" sizes=\"auto, (max-width: 508px) 100vw, 508px\" \/><\/p>\n<h3 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Differential-Phase-Shift-Keying-DPSK\"><\/span>Differential Phase Shift Keying (DPSK)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul style=\"text-align: justify;\">\n<li>DPSK is called non-coherent version of PSK. It doesn\u2019t need any synchronous carrier at demodulator.<\/li>\n<li>Input sequence of binary bits is modified such that next bit depends on previous bit.<\/li>\n<li>On the receiver side, the previous received bits are used to detect the present bit.<\/li>\n<\/ul>\n<h4 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"DPSK-Transmitter\"><\/span>DPSK Transmitter<span class=\"ez-toc-section-end\"><\/span><\/h4>\n<p style=\"text-align: justify;\">It consists of two operations:<br \/>\n(a) Differential encoding of input binary sequence. (b) PSK of encoded sequence.<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2873 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/transmitter.jpg\" alt=\"Transmitter\" width=\"413\" height=\"80\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/transmitter.jpg 413w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/transmitter-300x58.jpg 300w\" sizes=\"auto, (max-width: 413px) 100vw, 413px\" \/><\/p>\n<p style=\"text-align: justify;\">\u2022 The digital information content of binary content is encoded in terms of signal transitions.<br \/>\n\u2022 Let us consider a message signal with m(t) = 1010 and reference bit = 1 and find DPSK signal of it.<br \/>\n\u2022 m(t) = 1 0 1 0 (Reference bit = 1)<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2874 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/differential-phase-.jpg\" alt=\" Differential Phase Shift Keying\" width=\"562\" height=\"205\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/differential-phase-.jpg 562w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/differential-phase--300x109.jpg 300w\" sizes=\"auto, (max-width: 562px) 100vw, 562px\" \/><\/p>\n<h4 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"DPSK-Receiver\"><\/span>DPSK Receiver<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2875 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/dpsk-receiver.jpg\" alt=\"DPSK Receiver\" width=\"394\" height=\"228\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/dpsk-receiver.jpg 394w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/dpsk-receiver-300x174.jpg 300w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/dpsk-receiver-392x228.jpg 392w\" sizes=\"auto, (max-width: 394px) 100vw, 394px\" \/><span class=\"ez-toc-section-end\"><\/span><\/h4>\n<p style=\"text-align: justify;\"><strong>Advantages of DPSK<\/strong><\/p>\n<ul style=\"text-align: justify;\">\n<li>No need of synchronization or no need of carrier at receiver end.<\/li>\n<li>Bandwidth requirement is less.<\/li>\n<li>One input bit transmission depends on previous bit as well as present bit.<br \/>\nHence, T = 2T<sub>b<\/sub> (T = Symbol duration ; T<sub>b<\/sub> = Bit duration)<\/li>\n<\/ul>\n<p style=\"text-align: center;\">BW = 2\/T = 1\/T<sub>b <\/sub>= f<sub>b<\/sub><\/p>\n<p style=\"text-align: justify;\">Hence, minimum bandwidth in DPSK is equal to f<sub>b <\/sub>= maximum baseband signal frequency.<\/p>\n<p style=\"text-align: justify;\"><strong>Drawbacks<\/strong><\/p>\n<ul style=\"text-align: justify;\">\n<li>Probability of error is higher.<\/li>\n<li>As DPSK uses two successive bits for its reception, error in first bit creates error in second bit. Hence error propagation is more.<\/li>\n<li>Noise interference is more.<\/li>\n<\/ul>\n<h3 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Minimum-Shift-KeyingMSK\"><\/span>Minimum Shift Keying(MSK)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p style=\"text-align: justify;\">In digital radio communication, one of the key concern is the power in the sidelobes. A spectrum rich in harmonic content is likely to cause interference with the nearby channels. The abrupt change in phase in PSK gives rise to spectral components in high frequencies. Minimum shift keying (MSK) address this by changing phase in a continuous manner and is also known as continuous phase FSK (CPFSK).<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2877 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/minimum-shift-keying.jpg\" alt=\"Minimum Shift Keying\" width=\"320\" height=\"168\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/minimum-shift-keying.jpg 320w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/minimum-shift-keying-300x158.jpg 300w\" sizes=\"auto, (max-width: 320px) 100vw, 320px\" \/><\/p>\n<h4 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Two-important-differences-between-QPSK-and-MSK\"><\/span>Two important differences between QPSK and MSK<span class=\"ez-toc-section-end\"><\/span><\/h4>\n<p style=\"text-align: justify;\">In MSK the baseband waveform, that multiplies the quadrature carrier, is much \u201csmoother\u201d than the abrupt rectangular waveform of QPSK. While the spectrum of MSK has a main center lobe which is 1.5 times as wide as the main lobe of QPSK, the side lobes in MSK are relatively much smaller in comparison to the main lobe, making filtering much easier.<br \/>\nThe waveform of MSK exhibits phase continuity, i.e. there are not abrupt phase changes as in QPSK. As a result we avoid the Inter Symbol Interference(ISI) caused by nonlinear amplifiers.<\/p>\n<p style=\"text-align: justify;\"><strong>Note:<\/strong> Most important and useful feature of MSK is its phase continuity.<\/p>\n<h4 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Bandwidth-of-MSK\"><\/span>Bandwidth of MSK<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2878 size-full\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2024\/08\/bandwidth-of-msk.jpg\" alt=\"Bandwidth of MSK\" width=\"518\" height=\"128\" srcset=\"https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/bandwidth-of-msk.jpg 518w, https:\/\/www.madeeasy.in\/study\/wp-content\/uploads\/2024\/08\/bandwidth-of-msk-300x74.jpg 300w\" sizes=\"auto, (max-width: 518px) 100vw, 518px\" \/><span class=\"ez-toc-section-end\"><\/span><\/h4>\n<h4 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Advantages-of-MSK\"><\/span>Advantages of MSK<span class=\"ez-toc-section-end\"><\/span><\/h4>\n<ul style=\"text-align: justify;\">\n<li>The MSK waveforms are smoother as compared to QPSK.<\/li>\n<li>MSK have continuous phase in all the cases whereas QPSK has abrupt phase shift of \u03c0\/2 or \u03c0.<\/li>\n<li>MSK does not have amplitude variations whereas QPSK have abrupt amplitude variation.<\/li>\n<li>Main lobe of MSK is wider than QPSK so MSK contains around 99% of signal energy.<\/li>\n<li>To avoid ISI, QPSK needs BPF but in MSK it is not required.<\/li>\n<\/ul>\n<h4 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Disadvantages-of-MSK\"><\/span>Disadvantages of MSK<span class=\"ez-toc-section-end\"><\/span><\/h4>\n<ul>\n<li style=\"text-align: justify;\">The generation and detection of MSK is slightly complex, because of incorrect synchronization, phase jitter\u00a0can be present in MSK.<\/li>\n<\/ul>\n<p style=\"text-align: center;\"><a class=\"btn btn-danger\" role=\"button\" href=\"https:\/\/study.madeeasy.in\/ec\/communication-systems\/multiplexing\/\" target=\"_blank\" rel=\"noopener\">&lt;&lt; Previous<\/a> | <a class=\"btn btn-success\" role=\"button\" href=\"https:\/\/study.madeeasy.in\/ec\/communication-systems\/awgn-channels\/\" target=\"_blank\" rel=\"noopener\"> Next &gt;&gt;<\/a><br \/>\n<strong> Must Read: <\/strong> <a href=\"https:\/\/study.madeeasy.in\/subjects\/what-is-communication\/\" target=\"_blank\" rel=\"noopener\"><strong>What is Communication?<\/strong><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>As we have studied earlier about the base band pulse transmission, we have seen that the output of a PCM<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[758,6],"tags":[797,798,794,796,795],"class_list":["post-2863","post","type-post","status-publish","format-standard","hentry","category-communication-systems","category-ec","tag-digital-modulation-schemes","tag-dpsk-receiver","tag-gaussian-noise","tag-quadrature-amplitude-modulation","tag-signal-space-representation"],"_links":{"self":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/posts\/2863","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/comments?post=2863"}],"version-history":[{"count":0,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/posts\/2863\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/media?parent=2863"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/categories?post=2863"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/tags?post=2863"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}