A diplexer is a passive device that implements frequency domain multiplexing. Two ports (e.g., L and H) are multiplexed onto a third port (e.g., S). The signals on ports L and H occupy disjoint frequency bands. Consequently, the signals on L and H can coexist on port S without interfering with each other. Various components An electronic component is a basic electronic element usually packaged in a discrete form with two or more connecting leads or metallic pads. ... In telecommunications, multiplexing (also muxing or MUXing) is the combining of two or more information channels onto a common transmission medium using hardware called a multiplexer or (MUX). ...

Typically, the signal on port L will occupy a single low frequency band and the signal on port H will occupy a higher frequency band. In that situation, the diplexer consists of a lowpass filter connecting ports L and S and high pass filter connecting ports H and S. Ideally, all the signal power on port L is transferred to the S port and vice versa. All the signal power on port H is transferred to port S and vice versa. Ideally, the separation of the signals is complete. None of the low band signal is transferred from the S port to the H port. In the real world, some power will be lost, and some signal power will leak to the wrong port.

Television diplexer consisting of a high-pass filter (left) and a low-pass filter (right). The antenna is connected to the screw terminals to the left of center.

The diplexer, being a passive device, is reciprocal. The device itself doesn't have a notion of input or output. Image File history File links Download high resolution version (1493x941, 702 KB) Summary Television signal splitter, consisting of a hi-pass and a lo-pass filter. ... Image File history File links Download high resolution version (1493x941, 702 KB) Summary Television signal splitter, consisting of a hi-pass and a lo-pass filter. ...

The diplexer is different from a passive combiner or splitter. The combiner is not frequency selective. There also a power "loss" issue - a combiner takes all the power delivered to the S port and equally divides to the A and B ports. A diplexer does not.

A diplexer multiplexes two ports onto one port. We are not limited in the number of ports to multiplex. A three-port to one-port multiplexer is also known as a triplexer.

Common Uses

The chief advantage of a diplexer is it allows two different devices to share a common communications channel. Typically, the shared channel is a long piece of coaxial cable. Rather than run two separate cables, a single cable with diplexers at each end can be used. The plan is economic if the diplexers cost less than running the second cable.

The diplexers might be used to connect two receivers inside a building to two antennas that are some distance away using a single cable. Alternatively, the two transmitters might connect to two antennas.

A diplexer is called a duplexer when it connects a receiver and transmitter to the same antenna. In that case, the antenna is part of the multiplexed communications channel, so only one diplexer is needed. The design requirements for that duplexer are often severe: the receive and transmit frequency bands are often closely spaced and lots of isolation is required. 1) A duplexer is a device that combines two or more signals onto a common channel or medium to increase its transmission efficiency. ...

Industrial Applications

Diplexing is useful in reducing the number of radio antennas on a radio tower, reducing the weight and loading from wind and potential ice, as well as the necessary size of the tower itself. Diplexers must be carefully engineered: designed and tuned to prevent intermodulation and keep reflected power (VSWR) to a minimum for each input transmitter and frequency. While diplexers can combine a relatively wide bandwidth, the major limitation comes with the antenna itself, which must be sufficiently wideband to accept all of the signals being passed through it, and transfer them to the air efficiently. A yagi antenna Most simply, an antenna is an electronic component designed to send or receive radio waves. ... A transmitting tower is, in contrast to a radio mast, a free standing construction, which serves either as carrier for transmitting antennas or directly as transmitting antenna (radiating transmitting tower). ... For other uses, see Weight (disambiguation). ... Load may mean: Look up Load in Wiktionary, the free dictionary. ... For other uses, see Wind (disambiguation). ... This article is about water ice. ... In music, tuning is the process of producing or preparing to produce a certain pitch in relation to another, usually at the unison but often at some other interval. ... Intermodulation or intermodulation distortion (IMD), or intermod for short, is the result of two or more signals of different frequencies being mixed together, forming additional signals at frequencies that are not, in general, at harmonic frequencies (integer multiples) of either. ... In telecommunication, standing wave ratio (SWR) is the ratio of the amplitude of a partial standing wave at an antinode (maximum) to the amplitude at an adjacent node (minimum). ... Input3 is the term denoting either an entrance or changes which are inserted into a system and which activate/modify a process. ... For other uses, see Frequency (disambiguation). ... Bandwidth is the difference between the upper and lower cutoff frequencies of, for example, a filter, a communication channel, or a signal spectrum, and is typically measured in hertz. ... For the automotive term, see Wideband (automotive). ... In telecommunication, signaling has the following meanings: The use of signals for controlling communications. ... Look up air in Wiktionary, the free dictionary. ... tytytrtyty This article is about energy efficiency as a ratio. ...

One of the most massive diplexers in use is atop the Empire State Building in New York, where over a dozen FM radio stations transmit through one four-panel antenna. Another such setup is on a tower in Miami Gardens, serving the Miami and Fort Lauderdale media market. The Empire State Building is a 102-story Art Deco skyscraper in New York City at the intersection of Fifth Avenue and West 34th Street. ... New York, New York redirects here. ... FM broadcasting is a broadcast technology invented by Edwin Howard Armstrong that uses frequency modulation (FM) to provide high-fidelity sound over broadcast radio. ... A radio station is an audio (sound) broadcasting service, traditionally broadcast through the air as radio waves (a form of electromagnetic radiation) from a transmitter to an antenna and a thus to a receiving device. ... This article is about the city in Miami-Dade County, Florida. ... This article is about the city in Florida. ... Fort Lauderdale, known as the Venice of America, is a city located in Broward County, Florida. ... A media market, broadcast market, media region, designated market area, DMA or simply market is a region where the population can receive the same (or similar) television and radio station offerings, and may also include other types of media including newspapers and Internet content. ...

Also many other large UHF-/VHF-transmitters use diplexers. The number of transmitters, which can share an antenna is restricted by their frequency difference. Transmitters, whose frequencies are too close together cannot be combined by a diplexer in a well way.

Diplexers are also used at mediumwave broadcasting stations. However their use is not so common in this frequency range as the corresponding wavelength varies in the mediumwave band much more with the frequency than at the FM-band and so it is more practicable to use for each frequency a separate antenna as normally mediumwave transmission sites usually broadcasts as a rule only on 1 to 4 frequencies, while FM-broadcasting sites often uses 4 and more frequencies.

Nevertheles the use of diplexers can be sensitive as back-up device. So in case of maintenance work at one antenna of a mediumwave transmission site with two antennas working on two frequencies, the other antenna can be used for broadcasting both programmes. In other cases it is not possible to build a further antenna for the second transmitter, as there is not enough space on the site available. Than the diplexer is used permanently.

At longwave broadcasting sites diplexers are normally not used as these stations broadcast usually only on one frequency. A realization of diplexers for longwave broadcasting stations may be difficult, as the bandwidth ( 9 kHz) is high in relation to the transmission frequency.

At VLF-transmitters diplexers are also not used as for this frequency range their realisation is very difficult as huge tuned loading coils are used for the antenna fed at which very high voltages occur at transmitter operation.

Diplexers are also used for non-broadcast applications such as amateur radio. Broadcasting is the distribution of audio and/or video signals which transmit programs to an audience. ... Amateur radio station with modern solid-state transceiver featuring LCD and DSP capabilities Amateur radio, often called ham radio, is both a hobby and a service that uses various types of radio communications equipment to communicate with other radio amateurs for public service, recreation and self-training. ...

Residential

Small diplexers are also used in the home, allowing direct broadcast satellite TV signals from the dish to the receiver to piggyback on one regular coaxial cable, along with lower-frequency signals from an outdoor terrestrial TV antenna for local channels. This is useful in homes which are already pre-wired, because it eliminates the need to install extra cables. However, the pre-wired cables must be the higher-quality RG-6. The less-expensive RG-59 will not pass the higher frequency band (usually 950 to 1450 MHz) output by the satellite TV LNB. Direct broadcast satellite (DBS) is a term used to refer to satellite television broadcasts intended for home reception, also referred to as direct-to-home signals. ... Satellite television is television delivered by way of orbiting communications satellites located 37,000 km (22,300 miles) above the earths surface. ... Sky Digital mini-dish Astros mini-dish. Special dish for up to 16 satellite positions (Ku-band) Satellite dish antenna for C-Band Satellite Dishes installed on an apartment complex A satellite dish is a type of parabolic antenna designed with the specific purpose of transmitting signals to and... IRD may refer to the following: integrated receiver/decoder Inland Revenue Department, the taxation service for the New Zealand Government. ... A multiple piggyback. ... Coaxial Cable For the weapon, see coaxial weapon. ... Terrestrial television (also known as over-the-air or OTA) is the traditional method of television broadcast signal delivery, by radio waves. ... RG-6/U is a common type of coaxial cable used in a wide variety of residential and commercial applications. ... This article does not cite its references or sources. ... Ku-band LNB with both sides uncovered. ...

In this case, one diplexer joins the two signals together. Another diplexer then separates the signals to the receiver of the TV set and the IRD of the DBS set-top box. More complex systems have a distribution amplifier, which allows each IRD to access multiple LNBs with different antenna polarizations. These usually have an antenna input and a diplexer, so that the antenna signal is also distributed along with the satellite. An integrated receiver/decoder is an electronic device used to receive and decode digital signals. ... A set-top box (STB) or set-top unit (STU) is a device that connects to a television and an external source of signal, turning the signal into content which is then displayed on the television screen. ... In electrodynamics, polarization (also spelled polarisation) is the property of electromagnetic waves, such as light, that describes the direction of their transverse electric field. ...

Diplexing will not work with HDTV DBS systems, as they use the low broadcast/cable range (and the high range all the way up to 3 GHz) for the additional satellites.^{[citation needed]} This can itself be considered a form of triplexing. High-definition television (HDTV) means broadcast of television signals with a higher resolution than traditional formats (NTSC, SECAM, PAL) allow. ...

Diplexers are also commonly used to combine UHF TV and VHF TV and FM signals onto one downlead, which can then be split back into its component parts as required.

A DSL filter may also be considered a diplexer, because it splits baseband telephone audio and modulated data. However, the term is usually reserved for radio frequencies; and also such a filter may only remove the DSL from the phone side, but not the phone from the DSL side. A DSL filter is an analog low-pass filter installed on telephones and other analog devices to prevent interference between such devices and Digital Subscriber Line service operating on the same line. ... Baseband is an adjective that describes signals and systems whose range of frequencies is measured from 0 to a maximum bandwidth or highest signal frequency; it is sometimes used as a noun for a band of frequencies starting at 0. ... For other uses, see Telephone (disambiguation). ... Modulate Bob Moulds fifth solo album, released in 2002 after a four-year layoff. ... For other uses, see Data (disambiguation). ... Television signal splitter consisting of a hi-pass filter (left) and a low-pass filter (right). ... DSL may refer to: Damn Small Linux Dark and Shattered Lands, a MUD based loosely on Forgotten Realms and Dragonlance books. ...

See also

• Duplexer
• Power dividers and directional couplers
• Multiplexing

1) A duplexer is a device that combines two or more signals onto a common channel or medium to increase its transmission efficiency. ... Power dividers and directional couplers are passive devices used in the field of radio technology. ... In telecommunications, multiplexing (also muxing or MUXing) is the combining of two or more information channels onto a common transmission medium using hardware called a multiplexer or (MUX). ...

External links

• Use of diplexers in domestic TV distribution.