{"id":231,"date":"2015-08-29T15:50:00","date_gmt":"2015-08-29T15:50:00","guid":{"rendered":"http:\/\/machineryequipmentonline.com\/video-equipment\/uncategorized\/channel-encodingquadrature-amplitude-modulation\/"},"modified":"2015-08-29T15:50:00","modified_gmt":"2015-08-29T15:50:00","slug":"channel-encodingquadrature-amplitude-modulation","status":"publish","type":"post","link":"http:\/\/machineryequipmentonline.com\/video-equipment\/channel-encodingquadrature-amplitude-modulation\/","title":{"rendered":"Channel encoding:Quadrature amplitude modulation"},"content":{"rendered":"<div class=\"vtmpa6a0dc83d70595\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '61e5902552e2353963d8d2f1bd1f4a8f',\n\t\t'format' : 'iframe',\n\t\t'height' : 250,\n\t\t'width' : 300,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/61e5902552e2353963d8d2f1bd1f4a8f\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.vtmpa6a0dc83d70595 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.vtmpa6a0dc83d70595 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.vtmpa6a0dc83d70595 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.vtmpa6a0dc83d70595 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.vtmpa6a0dc83d70595 {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<h3 align=\"justify\">Quadrature amplitude modulation<\/h3>\n<p align=\"justify\">QAM is an extension of PSK in that some phasors are changed in amplitude as well as phase to provide increased bit representation. For instance, 16-QAM encoding increases the bit width of the modulation to 4 as shown in Figure 8.6. Twelve different carrier phasors are used, four of which have two amplitudes to provide further 4-bit combinations. Figure 8.7 depicts all possible carrier phase angles and amplitudes; it is known as a <i>constel- lation map<\/i>.  <\/p>\n<p align=\"justify\"><a href=\"http:\/\/lh3.googleusercontent.com\/-Ks3lVk_vl1Q\/VeHUn1TCdnI\/AAAAAAAB4AM\/pib2oE8Ig_Q\/s1600-h\/Channel-encoding-05702.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-right-width: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top-width: 0px; border-bottom-width: 0px; border-left-width: 0px; padding-top: 0px\" title=\"Channel encoding-0570\" border=\"0\" alt=\"Channel encoding-0570\" src=\"http:\/\/lh3.googleusercontent.com\/--KKy4pjYC_A\/VeHUw4SkJ9I\/AAAAAAAB4A0\/yyNN5e_agJ4\/Channel-encoding-0570_thumb.jpg?imgmax=800\" width=\"315\" height=\"419\" \/><\/a>  <\/p><div class=\"fnwmt6a0dc83d7069d\" ><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-0778475562755157\"\n     crossorigin=\"anonymous\"><\/script>\n<!-- 300x600 television-and-video -->\n<ins class=\"adsbygoogle\"\n     style=\"display:inline-block;width:300px;height:600px\"\n     data-ad-client=\"ca-pub-0778475562755157\"\n     data-ad-slot=\"6549443290\"><\/ins>\n<script>\n     (adsbygoogle = window.adsbygoogle || []).push({});\n<\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.fnwmt6a0dc83d7069d {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.fnwmt6a0dc83d7069d {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.fnwmt6a0dc83d7069d {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.fnwmt6a0dc83d7069d {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.fnwmt6a0dc83d7069d {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<div class=\"egave6a0dc83d70625\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '0c1eb4c533eaedb7b996f49a5a4983a9',\n\t\t'format' : 'iframe',\n\t\t'height' : 300,\n\t\t'width' : 160,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/0c1eb4c533eaedb7b996f49a5a4983a9\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.egave6a0dc83d70625 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.egave6a0dc83d70625 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.egave6a0dc83d70625 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.egave6a0dc83d70625 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.egave6a0dc83d70625 {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n\n<p align=\"justify\">A higher order of digital modulation may be employed, for example, in cable, namely 64-QAM encoding, in which each carrier phase\/amplitude represents one of 64 possible 6-bit combinations. The constellation map for 64-QAM is shown in Figure 8.8.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Quadrature amplitude modulation QAM is an extension of PSK in that some phasors are changed in amplitude as well as phase to provide increased bit representation. For instance, 16-QAM encoding increases the bit width of the modulation to 4 as shown in Figure 8.6. Twelve different carrier phasors are used, four of which have two [&hellip;]<br \/><a href=\"http:\/\/machineryequipmentonline.com\/video-equipment\/channel-encodingquadrature-amplitude-modulation\/\" class=\"more-link\" >Continue reading&#8230;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"aioseo_notices":[],"views":631,"_links":{"self":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts\/231"}],"collection":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/comments?post=231"}],"version-history":[{"count":0,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts\/231\/revisions"}],"wp:attachment":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/media?parent=231"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/categories?post=231"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/tags?post=231"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}