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A Demodulator (short |
A '''Demodulator''' (short '''Demod''') recovers (demodulates) the original information from an intermediate frequency (IF) that is provided to it by a [[tuner]]. The type of demodulator IC used for this task of information recovery is specific and dependent upon the nature of the signal transmission scheme involved. |
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In the case of [[analog TV]], the IF inputted into the demodulator contains the [[Wikipedia:Composite video|composite signal]] that was originally modulated onto the [[RF|RF carrier]]. After recovery, the demodulator outputs a CVSB signal, which will then need to be digitized through sampling techniques performed by a [[decoder|A/V decoder]]. |
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Some examples for digital Demods are: |
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In the case of [[digital TV]] transmission schemes, the IF inputted into the demodulator contains a [[MPEG-2 Transport Stream]] (TS) that was originally modulated onto the RF carrier. In the process of recovering that TS, digital demodulators will perform [[Wikipedia:Forward Error Correction|Forward Error Correction]] ([[Wikipedia:Convolutional Code|Convolutional Viterbi-]] and [[Wikipedia:Reed-Solomon_error_correction|Block-Reed-Solomon-Decoding]]). This whole process is sometimes referred to as RF-to-bits, for, unlike the case with analog IF demodulators, the recovered signal outputted from the digital demodulator is already a digital bit stream; specifically a TS. The TS will in turn be sent to a decoder in order to display (and, depending upon what format the underlying video content contained within the TS was encoded with, this could be a MPEG-2 or MPEG-4 decoder ... and either [[Hardware or Software Decoder?|hardware or software based]]). |
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==Demodulator Chipsets== |
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===Analogue IF Demodulators=== |
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{| class="wikitable sortable" |
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|+'''A Sortable List of Analog IF Demodulators''' |
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! Vendor !! Model !! Standards !! Linux Support !! class="unsortable"| Comments |
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| [[NXP]] (ex-[[Philips Semiconductors|Philips]]) || [[NXP TDA988x|TDA9887]] || PAL, SECAM and NTSC || {{Yes}} || - |
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| [[Xceive]] || [[Xceive XC3028|XC3028]] || NTSC, PAL || er, somewhat || firmware galore |
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| [[Xceive]] || [[Xceive XC5000|XC5000]] || NTSC, PAL || er, somewhat || firmware galore |
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|} |
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... and so on ... |
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===Digital Demodulators=== |
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{| class="wikitable sortable" |
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|+'''A Sortable List of Digital Demodulators''' |
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|- |
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! Vendor !! Model !! Standard !! Linux Support !! class="unsortable"| Comments |
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| [[Afatech]] || [[Afatech AF9005|AF9005]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]. A combo USB bridge & demod IC |
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| [[Afatech]] || [[Afatech AF9015|AF9015]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]. A combo USB bridge & demod IC |
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| [[Afatech]] || [[Afatech AF9035|AF9035]] || [[DVB-T]] || {{Yes}} || ; firmware required |
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| [[ATI/AMD]] || [[ATI/AMD Nxt2000|Nxt2000]] || [[ATSC]] || {{Unknown}} || Supports [[8-VSB]], [[QAM]]; firmware required |
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| [[ATI/AMD]] || [[ATI/AMD Nxt2002|Nxt2002]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]]; firmware required |
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| [[ATI/AMD]] || [[ATI/AMD Nxt2004|Nxt2004]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]]; firmware required |
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| [[ATI/AMD]] || [[ATI/AMD NXT6000|NXT6000]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]] |
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| [[ATI/AMD]] || [[ATI/AMD Theater 31x|Theater 31x]] || [[ATSC]] || {{no}} || Supports [[8-VSB]], [[QAM]] |
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| [[Atmel Corporation|Atmel]] || [[Atmel AT76C651|AT76C651]] || DVB-C || {{Unknown}} || supports [[QAM]] |
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| [[Commsonic]] || [[Commsonic CMS0014|CMS0014]] || [[DVB-S2]] || {{Unknown}} || [[QPSK]] 8PSK, 16APSK and 32APSK |
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| [[Conexant]] || [[Conexant CX24116|CX24116]] || [[DVB-S2]] || {{Unknown}} || |
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| [[Conexant]] || [[Conexant CX22700|CX22700]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]] |
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| [[Conexant]] || [[Conexant CX24110|CX24110]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]] |
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| [[DiBcom]] || [[DiBcom DIB3000M|DIB3000M]] || [[DVB-T]] || {{Yes}} || supports [[COFDM]] |
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| [[DiBcom]] || [[DiBcom DIB3000P|DIB3000P]] || [[DVB-T]] || {{Yes}} || supports ? |
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| [[DiBcom]] || [[DiBcom DiB7xxx|DiB7xxx]] || [[DVB-T]] || {{Yes}} || supports ? |
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| [[Tai-Hui|E3C]] || [[E3C EC168|EC168]] || [[DVB-T]] || exp || |
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| [[Eccincorp]] || [[Eccincorp ECC3100 (SkyPHY)|ECC3100 (SkyPHY)]] || [[DVB-S2]] || {{Unknown}} || |
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| [[Fujitsu]] || [[Fujitsu MB86A16|MB86A16]] || [[DVB-S]] || @mantis source (?) || supports [[QPSK]] |
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| [[Intel]] || || || || there are several intel demods that could be added here |
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| [[LG]] || [[LG DT3302|DT3302]] || [[ATSC]]|| {{Yes}} || Supports [[8-VSB]], [[QAM]] |
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| [[LG]] || [[LG DT3303|DT3303]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]] |
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| [[LSI Logic Corporation]] || [[LSI L64781|L64781]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]] |
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| [[LSI Logic Corporation]] || [[LSI L64782|L64782]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]] |
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| [[Microtune]] || [[Microtune MT8872|MT8872]] || [[DVB-T]] || {{Unknown}} || [[COFDM]] |
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| [[Montage]] || [[Montage M88DS3000|M88DS3000]] || [[DVB-S2]] || {{Yes}} || [[QPSK]] [[8PSK]], [[16APSK]] and [[32APSK]] |
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| [[Montage]] || [[Montage M88DS3000|M88DS3002]] || [[DVB-S2]] || {{Yes}} || [[QPSK]] [[8PSK]], [[16APSK]] and [[32APSK]] |
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| [[Montage]] || [[Montage M88DS3103|M88DS3103]] || [[DVB-S2]] || {{Yes}} || |
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| [[Oren]] || [[Oren or51211|or51211]] || [[ATSC]] || {{Yes}} || supports [[8-VSB]] and [[QAM]]; firmware required, however, no QAM capable firmware is known |
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| [[Oren]] || [[Oren or51132|or51132]] || [[ATSC]] || {{Yes}} || supports [[8-VSB]] and [[QAM]]; firmware required |
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| [[Philips Semiconductors|Philips]] || [[NXP TDA1002x|TDA10021]] || [[DVB-C]] || {{Yes}} || Supports [[QAM]] |
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| [[Philips Semiconductors|Philips]] || [[NXP TDA1004x|TDA10045]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]] |
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| [[Philips Semiconductors|Philips]] || [[NXP TDA1004x|TDA10046]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]] |
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| [[Philips Semiconductors|Philips]] || [[NXP TDA1004x|TDA10048]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]] |
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| [[Philips Semiconductors|Philips]] || [[Philips TDA8083|TDA8083]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]] |
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| [[Samsung]] || [[Samsung s5h1409|s5h1409]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]]. Also known as the Conexant CX24227 |
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| [[Samsung]] || [[Samsung s5h1411|s5h1411]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]]. |
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| [[Sony]] || [[Sony CXD2820|CXD2820]] || [[DVB-T2]] and also [[DVB-C]] and [[DVB-T]]|| {{Yes}} || supports [[COFDM]] (named OFDM in this [http://www.sony.net/Products/SC-HP/cx_news/vol60/pdf/cxd2820r.pdf source]) |
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| [[SPaSE]] || [[SPaSE SP8870|SP8870]] || [[DVB-T]] || {{Unknown}} || supports [[COFDM]] |
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| [[SPaSE]] || [[SPaSE SP8872|SP8872]] || [[DVB-T]] || {{Unknown}} || [[COFDM]] |
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| [[Silicon Labs]] || [[Silicon_Labs_si2168|si2168]] || [[DVB-C]], [[DVB-T2]] and [[DVB-T]] || {{only proprietary closed source}} || supports [[COFDM]], [[QAM]] |
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| [[STMicroelectronics]] || [[STMicroelectronics STV0297|STV0297]] || [[DVB-C]] || {{Yes}} || supports [[QAM]] |
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| [[STMicroelectronics]] || [[STMicroelectronics STV0299|STV0299]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]] |
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| [[STMicroelectronics]] || [[STMicroelectronics STB0899|STB0899]] || [[DVB-S2]] || {{Yes}} || supports [[8PSK]], [[QPSK]], [[16APSK]] |
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| [[STMicroelectronics]] || [[STMicroelectronics STV0900|STV0900/3]] || [[DVB-S2]] || {{Unknown}} ||supports [[QPSK]] |
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| [[STMicroelectronics]] || [[STMicroelectronics STV0900|STV0900]] || [[DVB-S2]] || {{Unknown}} || |
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| [[STMicroelectronics]] || [[STMicroelectronics STV0900|STV0900B]] || [[DVB-S2]] || {{Unknown}} || |
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| [[VLSI Technology]] || [[VLSI VES1893|VES1893]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]] |
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| [[VLSI Technology]] || [[VLSI VES1993|VES1993]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]] |
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| [[VLSI Technology]] || [[VLSI VES1820|VES1820]] || [[DVB-C]] || {{Yes}} || supports [[QAM]] |
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| [[Zarlink Semiconductor]] || [[Zarlink MT312|MT312]] || [[DVB-S]]/[[DSS]] || {{Yes}} || supports [[QPSK]] |
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| [[Zarlink Semiconductor]] || [[Zarlink MT352|MT352]] || [[DVB-T]] || {{Yes}} || supports [[COFDM]] |
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| [[Zarlink Semiconductor]] || [[Zarlink ZL10312|ZL10312]] || [[DVB-S]]/[[DSS]] || {{no}} || supports [[QPSK]] |
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| [[Zarlink Semiconductor]] || [[Zarlink ZL10313|ZL10313]] || [[DVB-S]]/[[DSS]] || {{no}} || supports [[QPSK]] |
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| [[Zoran]] || [[Zoran Cascade2|Cascade2 (CAS-220)]] || [[ATSC]] || {{Unknown}} || Supports [[8-VSB]], [[QAM]]. Formerly [[Oren]] |
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|} |
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...and so on ... |
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==Also see== |
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* [[List of Chipset Vendors]] |
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[[Category:Technology]] |
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[[Category:Hardware]] |
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[[Category:Demodulator]] |
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Latest revision as of 13:58, 7 June 2014
A Demodulator (short Demod) recovers (demodulates) the original information from an intermediate frequency (IF) that is provided to it by a tuner. The type of demodulator IC used for this task of information recovery is specific and dependent upon the nature of the signal transmission scheme involved.
In the case of analog TV, the IF inputted into the demodulator contains the composite signal that was originally modulated onto the RF carrier. After recovery, the demodulator outputs a CVSB signal, which will then need to be digitized through sampling techniques performed by a A/V decoder.
In the case of digital TV transmission schemes, the IF inputted into the demodulator contains a MPEG-2 Transport Stream (TS) that was originally modulated onto the RF carrier. In the process of recovering that TS, digital demodulators will perform Forward Error Correction (Convolutional Viterbi- and Block-Reed-Solomon-Decoding). This whole process is sometimes referred to as RF-to-bits, for, unlike the case with analog IF demodulators, the recovered signal outputted from the digital demodulator is already a digital bit stream; specifically a TS. The TS will in turn be sent to a decoder in order to display (and, depending upon what format the underlying video content contained within the TS was encoded with, this could be a MPEG-2 or MPEG-4 decoder ... and either hardware or software based).
Demodulator Chipsets
Analogue IF Demodulators
| Vendor | Model | Standards | Linux Support | Comments |
|---|---|---|---|---|
| NXP (ex-Philips) | TDA9887 | PAL, SECAM and NTSC | ✔ Yes | - |
| Xceive | XC3028 | NTSC, PAL | er, somewhat | firmware galore |
| Xceive | XC5000 | NTSC, PAL | er, somewhat | firmware galore |
... and so on ...
Digital Demodulators
...and so on ...