A Tower Mounted Amplifier ( TMA ), or Mast Head Amplifier ( MHA ), is a low-noise amplifier (LNA) mounted as close as practical to the antenna in mobile masts or base transceiver stations . A TMA reduces the base transceiver station noise figure (NF) and therefore improves its overall sensitivity ; in other words the mobile mast is able to receive weaker signals. The power to feed the amplifier (in the top of the mast) is usually a DC component on the same coaxial cable that feeds the antenna, otherwise an extra power cable has to be run to the TMA/MHA to supply it with power.
21-654: [REDACTED] Look up TMA or tma in Wiktionary, the free dictionary. TMA may refer to: Science [ edit ] Tense–Modality–Aspect or tense–aspect–mood , grammatical system Tetramethylammonium ion or its salts Thermomechanical analysis Third man argument , a philosophical criticism of Plato's theory of Forms Thrombotic microangiopathy Tissue microarray , device for analysing many histological tissue samples Transcription mediated amplification Trimethylamine , (CH 3 ) 3 N,
42-483: A collective term for diseases of blue agave Transportation [ edit ] Aviation [ edit ] Terminal Manoeuvring Area / Terminal Control Area - aviation term for a controlled high-volume airspace Trans Maldivian Airways TMA Cargo , Lebanese airline Engineering [ edit ] TMA Engineering , UK Truck-mounted attenuator , crash attenuator Space exploration [ edit ] Russian Soyuz spacecraft missions; TMA are
63-483: A collective term for diseases of blue agave Transportation [ edit ] Aviation [ edit ] Terminal Manoeuvring Area / Terminal Control Area - aviation term for a controlled high-volume airspace Trans Maldivian Airways TMA Cargo , Lebanese airline Engineering [ edit ] TMA Engineering , UK Truck-mounted attenuator , crash attenuator Space exploration [ edit ] Russian Soyuz spacecraft missions; TMA are
84-550: A marketing and creative agency owned by Omnicom Group TMA Awards of the UK Theatrical Management Association Total Media Agency , a Japanese pornographic video production company The Mod Archive , a web index and archive of playable music module files The Magnus Archives , a fictional horror podcast produced by Rusty Quill " The Magician's Apprentice ", a 2015 episode of Doctor Who Topics referred to by
105-431: A marketing and creative agency owned by Omnicom Group TMA Awards of the UK Theatrical Management Association Total Media Agency , a Japanese pornographic video production company The Mod Archive , a web index and archive of playable music module files The Magnus Archives , a fictional horror podcast produced by Rusty Quill " The Magician's Apprentice ", a 2015 episode of Doctor Who Topics referred to by
126-683: A philosophical criticism of Plato's theory of Forms Thrombotic microangiopathy Tissue microarray , device for analysing many histological tissue samples Transcription mediated amplification Trimethylamine , (CH 3 ) 3 N, a simple amine Trimethylaluminium , (CH 3 ) 3 Al Trimesic acid Psychedelic or hallucinogenic drugs that are isomeric-substituted amphetamines: 3,4,5-trimethoxyamphetamine ( TMA ) 2,4,5-trimethoxyamphetamine ( TMA-2 ) 2,3,4-trimethoxyamphetamine ( TMA-3 ) 2,3,5-trimethoxyamphetamine ( TMA-4 ) 2,3,6-trimethoxyamphetamine ( TMA-5 ) 2,4,6-trimethoxyamphetamine ( TMA-6 ) Tristeza y muerte de agave ,
147-440: A simple amine Trimethylaluminium , (CH 3 ) 3 Al Trimesic acid Psychedelic or hallucinogenic drugs that are isomeric-substituted amphetamines: 3,4,5-trimethoxyamphetamine ( TMA ) 2,4,5-trimethoxyamphetamine ( TMA-2 ) 2,3,4-trimethoxyamphetamine ( TMA-3 ) 2,3,5-trimethoxyamphetamine ( TMA-4 ) 2,3,6-trimethoxyamphetamine ( TMA-5 ) 2,4,6-trimethoxyamphetamine ( TMA-6 ) Tristeza y muerte de agave ,
168-459: A typical receiver: Antenna - Connecting Cable (stage 1) - Receiver (stage 2). S y s t e m N o i s e F i g u r e = F 1 + F 2 − 1 G 1 {\displaystyle SystemNoiseFigure=F_{1}+{\frac {F_{2}-1}{G_{1}}}} The first stage after the antenna is actually the connecting cable. Therefore: What can be done to improve
189-466: Is different from Wikidata All article disambiguation pages All disambiguation pages TMA [REDACTED] Look up TMA or tma in Wiktionary, the free dictionary. TMA may refer to: Science [ edit ] Tense–Modality–Aspect or tense–aspect–mood , grammatical system Tetramethylammonium ion or its salts Thermomechanical analysis Third man argument ,
210-442: Is different from Wikidata All article disambiguation pages All disambiguation pages Tower Mounted Amplifier In two way communications systems, there are occasions when one way, one link, is weaker than the other, normally referenced as unbalanced links. This can be fixed by making the transmitter on that link stronger or the receiver more sensitive to weaker signals. TMAs are used in mobile networks to improve
231-693: The Russian initials for Transport Modified Anthropometric Soyuz TMA-1 , launched 30 October 2002 Soyuz TMA-2 , launched 26 April 2003 Soyuz TMA-3 , launched 18 October 2003 Soyuz TMA-4 , launched 19 April 2004 Soyuz TMA-5 , launched 14 October 2004 Soyuz TMA-6 , launch 15 April 2005 other Soyuz-TMA missions Military [ edit ] Target Motion Analysis , by submarine SONAR Tanzania Military Academy Yugoslavian landmines: TMA-1 mine TMA-2 mine TMA-3 mine TMA-4 mine Communications [ edit ] Television Market Area , official designation of
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#1732771803348252-638: The Russian initials for Transport Modified Anthropometric Soyuz TMA-1 , launched 30 October 2002 Soyuz TMA-2 , launched 26 April 2003 Soyuz TMA-3 , launched 18 October 2003 Soyuz TMA-4 , launched 19 April 2004 Soyuz TMA-5 , launched 14 October 2004 Soyuz TMA-6 , launch 15 April 2005 other Soyuz-TMA missions Military [ edit ] Target Motion Analysis , by submarine SONAR Tanzania Military Academy Yugoslavian landmines: TMA-1 mine TMA-2 mine TMA-3 mine TMA-4 mine Communications [ edit ] Television Market Area , official designation of
273-500: The U.S. Federal Communications Commission Tower Mounted Amplifier or masthead amplifier Medicine [ edit ] Tissue microarray , a paraffin block in which tissue cores are assembled in array fashion to allow multiplex histological analysis Other [ edit ] Tehsil Municipal Administration Tejano Music Awards Texas A&M Maritime Academy, at Texas A&M University at Galveston Theatre Musicians Association , US TMA ( The Marketing Arm ),
294-500: The U.S. Federal Communications Commission Tower Mounted Amplifier or masthead amplifier Medicine [ edit ] Tissue microarray , a paraffin block in which tissue cores are assembled in array fashion to allow multiplex histological analysis Other [ edit ] Tehsil Municipal Administration Tejano Music Awards Texas A&M Maritime Academy, at Texas A&M University at Galveston Theatre Musicians Association , US TMA ( The Marketing Arm ),
315-1027: The antenna and described by F 1 {\displaystyle F_{1}} and G 1 {\displaystyle G_{1}} . The relationship of the stages is known as the Friis formula . S y s t e m N o i s e F i g u r e = F 1 + F 2 − 1 G 1 + F 3 − 1 G 1 × G 2 + ⋯ + F n − 1 G 1 × G 2 × G 3 × ⋯ × G n − 1 {\displaystyle SystemNoiseFigure=F_{1}+{\frac {F_{2}-1}{G_{1}}}+{\frac {F_{3}-1}{G_{1}\times G_{2}}}+\cdots +{\frac {F_{n}-1}{G_{1}\times G_{2}\times G_{3}\times \cdots \times G_{n-1}}}} Note that: Start with
336-481: The receiver is so lossy ( too thin or too long ) that the signal weakens from the antenna before reaching the receiver; therefore it may be decided to install TMAs from the start to make the system viable. In other words, the TMA can only partially correct, or palliate, the link imbalance. In a receiver, the receiving path starts with the signal originating at the antenna. Then the signal is amplified in further stages within
357-946: The receiver to pick up very weak signals? It must have a lower noise figure; that is when the TMA comes into use. It is a chain of 4 modules: antenna - short connecting cable (stage 1) - TMA (stage 2) - longer connecting cable (stage 3) - receiver (stage 4) Updating the Friis formula with this case, the noise figure is now: S y s t e m N o i s e F i g u r e = F 1 + F 2 − 1 1 + F 3 − 1 1 × G 2 + F 4 − 1 1 × G 2 × G 3 {\displaystyle SystemNoiseFigure=F_{1}+{\frac {F_{2}-1}{1}}+{\frac {F_{3}-1}{1\times G_{2}}}+{\frac {F_{4}-1}{1\times G_{2}\times G_{3}}}} In this way,
378-422: The receiver. It is actually not amplified all at once but in stages, with some stages producing other changes ( like changing the signal's frequency ). The principle can be demonstrated mathematically; the receiver's noise figure is calculated by modularly assessing each amplifier stage. Each stage consists of a noise figure (F) and an amount of amplification, or gain (G). So amplifier number 1 will be right after
399-403: The same term [REDACTED] This disambiguation page lists articles associated with the title TMA . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=TMA&oldid=1212512762 " Category : Disambiguation pages Hidden categories: Short description
420-403: The same term [REDACTED] This disambiguation page lists articles associated with the title TMA . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=TMA&oldid=1212512762 " Category : Disambiguation pages Hidden categories: Short description
441-412: The sensitivity of the uplink in mobile phone masts. Since the transmitter in a mobile phone it cannot be easily modified to transmit stronger signals. Improving the uplink translates into a combination of better coverage and mobile transmitting at less power, which in turn implies a lower drain from its batteries, thus a longer battery charge. There are occasions when the cable between the antenna and
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