{"id":236,"date":"2020-11-29T08:21:39","date_gmt":"2020-11-29T13:21:39","guid":{"rendered":"https:\/\/www.alpharithms.com\/?post_type=term&p=236"},"modified":"2021-07-27T08:08:34","modified_gmt":"2021-07-27T12:08:34","slug":"frequency-division-multiplexing-fdm","status":"publish","type":"post","link":"https:\/\/www.alpharithms.com\/frequency-division-multiplexing-fdm-392108\/","title":{"rendered":"Frequency Division Multiplexing (FDM)"},"content":{"rendered":"

Frequency Division Multiplexing (FDM) is a circuit switching protocol<\/a> by which network connectivity is allocated across a frequency band. Each network connection is allocated a specific frequency band in which data can be transferred.<\/p>\n

FDM is used among technologies such as FM radio; a total frequency spectrum of 88Mhz-108MHz is allocated for network communications (R<\/a>). The FM spectrum is divided into channels, each 200Hz (.2Mhz) wide. The “bandwidth” of FM radio can be said to be 200Hz (R<\/a>).<\/p>\n

In the image below, a 400Mhz wide spectrum has been sub-divided into 4 x 100MHz bands each of which would have 400\/100 transmission capacity of the total network but could transmit freely without delay from other bands.<\/p>\n

\"frequency
In FDM, the spectrum of available frequencies is subdivided into separate bands assigned to network devices.<\/figcaption><\/figure>\n

In FDM, each networked device is permitted to transmit freely on their assigned band but cannot use the bandwidth allocated for another network system. As such, the entirety of a network’s transmission capacity may be underutilized during silent periods when end systems are not transmitting data.<\/p>\n

In such cases, bandwidth is not dynamically expanded to allow higher throughput for active devices and, effectively, sits idle until used. In the context of FM, this is called\u00a0dead air<\/em>. FDM is similar to time-division multiplexing<\/a> in this regard.<\/p>\n","protected":false},"excerpt":{"rendered":"

Frequency Division Multiplexing (FDM) is a circuit switching protocol by which network connectivity is allocated across a frequency band. Each network connection is allocated a specific frequency band in which data can be transferred. FDM is used among technologies such as FM radio; a total frequency spectrum of 88Mhz-108MHz is allocated for network communications (R). […]<\/p>\n","protected":false},"author":2,"featured_media":2472,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"categories":[3,260],"tags":[108,461,105,107,106],"acf":[],"_links":{"self":[{"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/posts\/236"}],"collection":[{"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/comments?post=236"}],"version-history":[{"count":5,"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/posts\/236\/revisions"}],"predecessor-version":[{"id":251,"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/posts\/236\/revisions\/251"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/media\/2472"}],"wp:attachment":[{"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/media?parent=236"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/categories?post=236"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.alpharithms.com\/wp-json\/wp\/v2\/tags?post=236"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}