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A Demodulator (short: [[Demod]]) recovers the original information (demodulates) from the downconverted received RF signal. In case of digital TV this is the [[MPEG2 Transport Stream]], in case of analogue TV the [[Composite Signal]].
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 [[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]].


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]]).
{| border="1" cellpadding="5" cellspacing="0" align="center"

|+'''Some Examples for Digital Demods are'''
==Demodulator Chipsets==

===Analogue IF Demodulators===

{| class="wikitable sortable"
|+'''A Sortable List of Analog IF Demodulators'''
|-
|-
! Vendor !! Model !! Standards !! Linux Support !! class="unsortable"| Comments
! style="background:#ffdead;" | Model
! style="background:#ffdead;" | Type and Vendor
|-
|-
| [[NXP]] (ex-[[Philips Semiconductors|Philips]]) || [[NXP TDA988x|TDA9887]] || PAL, SECAM and NTSC || {{Yes}} || -
! style="background:#efefef;" | [[NXT6000]]
|-
! [[DVB-T]]/[[COFDM]] Demod produced by [[ATI]]
| [[Xceive]] || [[Xceive XC3028|XC3028]] || NTSC, PAL || er, somewhat || firmware galore
|-
|-
| [[Xceive]] || [[Xceive XC5000|XC5000]] || NTSC, PAL || er, somewhat || firmware galore
! style="background:#efefef;" | [[AT76C651]]
|}
! [[DVB-T]]/[[COFDM]] Demod produced by [[Atmel]]
... and so on ...

===Digital Demodulators===
{| class="wikitable sortable"
|+'''A Sortable List of Digital Demodulators'''
|-
|-
! Vendor !! Model !! Standard !! Linux Support !! class="unsortable"| Comments
! style="background:#efefef;" | [[CX24110]]
! [[DVB-T]]/[[COFDM]] Demod produced by [[Connexant]]
|-
|-
| [[Afatech]] || [[Afatech AF9005|AF9005]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]. A combo USB bridge & demod IC
! style="background:#efefef;" | [[DIB3000M]]
! [[DVB-T]]/[[COFDM]] Demod produced by [[DIBCom]]
|-
|-
| [[Afatech]] || [[Afatech AF9015|AF9015]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]. A combo USB bridge & demod IC
! style="background:#efefef;" | [[L64781]]
! [[DVB-T]]/[[COFDM]] Demod produced by [[LSI Logic]]
|-
|-
| [[Afatech]] || [[Afatech AF9035|AF9035]] || [[DVB-T]] || {{Yes}} || ; firmware required
! style="background:#efefef;" | [[L64782]]
! [[DVB-T]]/[[COFDM]] Demod produced by [[LSI Logic]]
|-
|-
| [[ATI/AMD]] || [[ATI/AMD Nxt2000|Nxt2000]] || [[ATSC]] || {{Unknown}} || Supports [[8-VSB]], [[QAM]]; firmware required
! style="background:#efefef;" | [[MT8872]]/[[SP8872]]
! [[DVB-T]]/[[COFDM]] Demod produced by [[Microtune]]
|-
|-
| [[ATI/AMD]] || [[ATI/AMD Nxt2002|Nxt2002]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]]; firmware required
! style="background:#efefef;" | [[TDA10021]]
! [[DVB-C]]/[[QAM]] Demod produced by [[Philips Semiconductors]]
|-
|-
| [[ATI/AMD]] || [[ATI/AMD Nxt2004|Nxt2004]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]]; firmware required
! style="background:#efefef;" | [[TDA10045]]
|-
! [[DVB-T]]/[[COFDM]] Demod produced by [[Philips Semiconductors]]
| [[ATI/AMD]] || [[ATI/AMD NXT6000|NXT6000]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]
|-
| [[ATI/AMD]] || [[ATI/AMD Theater 31x|Theater 31x]] || [[ATSC]] || {{no}} || Supports [[8-VSB]], [[QAM]]
|-
|-
| [[Atmel Corporation|Atmel]] || [[Atmel AT76C651|AT76C651]] || DVB-C || {{Unknown}} || supports [[QAM]]
! style="background:#efefef;" | [[TDA10046]]
! [[DVB-T]]/[[COFDM]] Demod produced by [[Philips Semiconductors]]
|-
|-
| [[Commsonic]] || [[Commsonic CMS0014|CMS0014]] || [[DVB-S2]] || {{Unknown}} || [[QPSK]] 8PSK, 16APSK and 32APSK
! style="background:#efefef;" | [[TDA8083]]
! [[DVB-S]]/[[QPSK]] Demod produced by [[Philips Semiconductors]]
|-
|-
| [[Conexant]] || [[Conexant CX24116|CX24116]] || [[DVB-S2]] || {{Unknown}} ||
! style="background:#efefef;" | [[SP8870]]
! [[DVB-T]]/[[COFDM]] Demod produced by [[Spase]]
|-
|-
| [[Conexant]] || [[Conexant CX22700|CX22700]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]
! style="background:#efefef;" | [[STV2097]]
! [[DVB-C]]/[[QAM]] Demod produced by [[ST Semiconductors]]
|-
|-
| [[Conexant]] || [[Conexant CX24110|CX24110]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]]
! style="background:#efefef;" | [[STV2099]]
! [[DVB-S]]/[[QPSK]] Demod produced by [[ST Semiconductors]]
|-
|-
| [[DiBcom]] || [[DiBcom DIB3000M|DIB3000M]] || [[DVB-T]] || {{Yes}} || supports [[COFDM]]
! style="background:#efefef;" | [[VES1893]]
! [[DVB-S]]/[[QPSK]] Demod produced by [[VLSI Technology]]
|-
|-
| [[DiBcom]] || [[DiBcom DIB3000P|DIB3000P]] || [[DVB-T]] || {{Yes}} || supports ?
! style="background:#efefef;" | [[VES1993]]
! [[DVB-S]]/[[QPSK]] Demod produced by [[VLSI Technology]]
|-
|-
| [[DiBcom]] || [[DiBcom DiB7xxx|DiB7xxx]] || [[DVB-T]] || {{Yes}} || supports ?
! style="background:#efefef;" | [[VES1820]]
! [[DVB-C]]/[[QAM]] Demod produced by [[VLSI Technology]]
|-
|-
| [[Tai-Hui|E3C]] || [[E3C EC168|EC168]] || [[DVB-T]] || exp ||
! style="background:#efefef;" | [[MT312]]
! [[DVB-S]]/[[DSS]]/[[QPSK]] Demod produced by [[Zarlink Semiconductors]]
|-
|-
| [[Eccincorp]] || [[Eccincorp ECC3100 (SkyPHY)|ECC3100 (SkyPHY)]] || [[DVB-S2]] || {{Unknown}} ||
! style="background:#efefef;" | [[ZL10312]]
! [[DVB-S]]/[[DSS]]/[[QPSK]] Demod produced by [[Zarlink Semiconductors]]
|-
|-
| [[Fujitsu]] || [[Fujitsu MB86A16|MB86A16]] || [[DVB-S]] || @mantis source (?) || supports [[QPSK]]
! style="background:#efefef;" | [[ZL10313]]
! [[DVB-S]]/[[DSS]]/[[QPSK]] Demod produced by [[Zarlink Semiconductors]]
|-
|-
| [[Intel]] || || || || there are several intel demods that could be added here
|-
| [[LG]] || [[LG DT3302|DT3302]] || [[ATSC]]|| {{Yes}} || Supports [[8-VSB]], [[QAM]]
|-
| [[LG]] || [[LG DT3303|DT3303]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]]
|-
| [[LSI Logic Corporation]] || [[LSI L64781|L64781]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]
|-
| [[LSI Logic Corporation]] || [[LSI L64782|L64782]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]
|-
| [[Microtune]] || [[Microtune MT8872|MT8872]] || [[DVB-T]] || {{Unknown}} || [[COFDM]]
|-
| [[Montage]] || [[Montage M88DS3000|M88DS3000]] || [[DVB-S2]] || {{Yes}} || [[QPSK]] [[8PSK]], [[16APSK]] and [[32APSK]]
|-
| [[Montage]] || [[Montage M88DS3000|M88DS3002]] || [[DVB-S2]] || {{Yes}} || [[QPSK]] [[8PSK]], [[16APSK]] and [[32APSK]]
|-
| [[Montage]] || [[Montage M88DS3103|M88DS3103]] || [[DVB-S2]] || {{Yes}} ||
|-
| [[Oren]] || [[Oren or51211|or51211]] || [[ATSC]] || {{Yes}} || supports [[8-VSB]] and [[QAM]]; firmware required, however, no QAM capable firmware is known
|-
| [[Oren]] || [[Oren or51132|or51132]] || [[ATSC]] || {{Yes}} || supports [[8-VSB]] and [[QAM]]; firmware required
|-
| [[Philips Semiconductors|Philips]] || [[NXP TDA1002x|TDA10021]] || [[DVB-C]] || {{Yes}} || Supports [[QAM]]
|-
| [[Philips Semiconductors|Philips]] || [[NXP TDA1004x|TDA10045]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]
|-
| [[Philips Semiconductors|Philips]] || [[NXP TDA1004x|TDA10046]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]
|-
| [[Philips Semiconductors|Philips]] || [[NXP TDA1004x|TDA10048]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]
|-
| [[Philips Semiconductors|Philips]] || [[Philips TDA8083|TDA8083]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]]
|-
| [[Samsung]] || [[Samsung s5h1409|s5h1409]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]]. Also known as the Conexant CX24227
|-
| [[Samsung]] || [[Samsung s5h1411|s5h1411]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]].
|-
| [[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])
|-
| [[SPaSE]] || [[SPaSE SP8870|SP8870]] || [[DVB-T]] || {{Unknown}} || supports [[COFDM]]
|-
| [[SPaSE]] || [[SPaSE SP8872|SP8872]] || [[DVB-T]] || {{Unknown}} || [[COFDM]]
|-
| [[Silicon Labs]] || [[Silicon_Labs_si2168|si2168]] || [[DVB-C]], [[DVB-T2]] and [[DVB-T]] || {{only proprietary closed source}} || supports [[COFDM]], [[QAM]]
|-
| [[STMicroelectronics]] || [[STMicroelectronics STV0297|STV0297]] || [[DVB-C]] || {{Yes}} || supports [[QAM]]
|-
| [[STMicroelectronics]] || [[STMicroelectronics STV0299|STV0299]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]]
|-
| [[STMicroelectronics]] || [[STMicroelectronics STB0899|STB0899]] || [[DVB-S2]] || {{Yes}} || supports [[8PSK]], [[QPSK]], [[16APSK]]
|-
| [[STMicroelectronics]] || [[STMicroelectronics STV0900|STV0900/3]] || [[DVB-S2]] || {{Unknown}} ||supports [[QPSK]]
|-
| [[STMicroelectronics]] || [[STMicroelectronics STV0900|STV0900]] || [[DVB-S2]] || {{Unknown}} ||
|-
| [[STMicroelectronics]] || [[STMicroelectronics STV0900|STV0900B]] || [[DVB-S2]] || {{Unknown}} ||
|-
| [[VLSI Technology]] || [[VLSI VES1893|VES1893]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]]
|-
| [[VLSI Technology]] || [[VLSI VES1993|VES1993]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]]
|-
| [[VLSI Technology]] || [[VLSI VES1820|VES1820]] || [[DVB-C]] || {{Yes}} || supports [[QAM]]
|-
| [[Zarlink Semiconductor]] || [[Zarlink MT312|MT312]] || [[DVB-S]]/[[DSS]] || {{Yes}} || supports [[QPSK]]
|-
| [[Zarlink Semiconductor]] || [[Zarlink MT352|MT352]] || [[DVB-T]] || {{Yes}} || supports [[COFDM]]
|-
| [[Zarlink Semiconductor]] || [[Zarlink ZL10312|ZL10312]] || [[DVB-S]]/[[DSS]] || {{no}} || supports [[QPSK]]
|-
| [[Zarlink Semiconductor]] || [[Zarlink ZL10313|ZL10313]] || [[DVB-S]]/[[DSS]] || {{no}} || supports [[QPSK]]
|-
| [[Zoran]] || [[Zoran Cascade2|Cascade2 (CAS-220)]] || [[ATSC]] || {{Unknown}} || Supports [[8-VSB]], [[QAM]]. Formerly [[Oren]]
|}
|}
...and so on ...

==Also see==
* [[List of Chipset Vendors]]

[[Category:Technology]]
[[Category:Hardware]]
[[Category:Demodulator]]

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

A Sortable List of Analog 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

A Sortable List of Digital Demodulators
Vendor Model Standard Linux Support Comments
Afatech AF9005 DVB-T ✔ Yes Supports COFDM. A combo USB bridge & demod IC
Afatech AF9015 DVB-T ✔ Yes Supports COFDM. A combo USB bridge & demod IC
Afatech AF9035 DVB-T ✔ Yes ; firmware required
ATI/AMD Nxt2000 ATSC ? Unknown Supports 8-VSB, QAM; firmware required
ATI/AMD Nxt2002 ATSC ✔ Yes Supports 8-VSB, QAM; firmware required
ATI/AMD Nxt2004 ATSC ✔ Yes Supports 8-VSB, QAM; firmware required
ATI/AMD NXT6000 DVB-T ✔ Yes Supports COFDM
ATI/AMD Theater 31x ATSC ✘ No Supports 8-VSB, QAM
Atmel AT76C651 DVB-C ? Unknown supports QAM
Commsonic CMS0014 DVB-S2 ? Unknown QPSK 8PSK, 16APSK and 32APSK
Conexant CX24116 DVB-S2 ? Unknown
Conexant CX22700 DVB-T ✔ Yes Supports COFDM
Conexant CX24110 DVB-S ✔ Yes supports QPSK
DiBcom DIB3000M DVB-T ✔ Yes supports COFDM
DiBcom DIB3000P DVB-T ✔ Yes supports ?
DiBcom DiB7xxx DVB-T ✔ Yes supports ?
E3C EC168 DVB-T exp
Eccincorp ECC3100 (SkyPHY) DVB-S2 ? Unknown
Fujitsu MB86A16 DVB-S @mantis source (?) supports QPSK
Intel there are several intel demods that could be added here
LG DT3302 ATSC ✔ Yes Supports 8-VSB, QAM
LG DT3303 ATSC ✔ Yes Supports 8-VSB, QAM
LSI Logic Corporation L64781 DVB-T ✔ Yes Supports COFDM
LSI Logic Corporation L64782 DVB-T ✔ Yes Supports COFDM
Microtune MT8872 DVB-T ? Unknown COFDM
Montage M88DS3000 DVB-S2 ✔ Yes QPSK 8PSK, 16APSK and 32APSK
Montage M88DS3002 DVB-S2 ✔ Yes QPSK 8PSK, 16APSK and 32APSK
Montage M88DS3103 DVB-S2 ✔ Yes
Oren or51211 ATSC ✔ Yes supports 8-VSB and QAM; firmware required, however, no QAM capable firmware is known
Oren or51132 ATSC ✔ Yes supports 8-VSB and QAM; firmware required
Philips TDA10021 DVB-C ✔ Yes Supports QAM
Philips TDA10045 DVB-T ✔ Yes Supports COFDM
Philips TDA10046 DVB-T ✔ Yes Supports COFDM
Philips TDA10048 DVB-T ✔ Yes Supports COFDM
Philips TDA8083 DVB-S ✔ Yes supports QPSK
Samsung s5h1409 ATSC ✔ Yes Supports 8-VSB, QAM. Also known as the Conexant CX24227
Samsung s5h1411 ATSC ✔ Yes Supports 8-VSB, QAM.
Sony CXD2820 DVB-T2 and also DVB-C and DVB-T ✔ Yes supports COFDM (named OFDM in this source)
SPaSE SP8870 DVB-T ? Unknown supports COFDM
SPaSE SP8872 DVB-T ? Unknown COFDM
Silicon Labs si2168 DVB-C, DVB-T2 and DVB-T Template:Only proprietary closed source supports COFDM, QAM
STMicroelectronics STV0297 DVB-C ✔ Yes supports QAM
STMicroelectronics STV0299 DVB-S ✔ Yes supports QPSK
STMicroelectronics STB0899 DVB-S2 ✔ Yes supports 8PSK, QPSK, 16APSK
STMicroelectronics STV0900/3 DVB-S2 ? Unknown supports QPSK
STMicroelectronics STV0900 DVB-S2 ? Unknown
STMicroelectronics STV0900B DVB-S2 ? Unknown
VLSI Technology VES1893 DVB-S ✔ Yes supports QPSK
VLSI Technology VES1993 DVB-S ✔ Yes supports QPSK
VLSI Technology VES1820 DVB-C ✔ Yes supports QAM
Zarlink Semiconductor MT312 DVB-S/DSS ✔ Yes supports QPSK
Zarlink Semiconductor MT352 DVB-T ✔ Yes supports COFDM
Zarlink Semiconductor ZL10312 DVB-S/DSS ✘ No supports QPSK
Zarlink Semiconductor ZL10313 DVB-S/DSS ✘ No supports QPSK
Zoran Cascade2 (CAS-220) ATSC ? Unknown Supports 8-VSB, QAM. Formerly Oren

...and so on ...

Also see

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