Demodulator: Difference between revisions
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| [[Afatech]] || [[Afatech AF9015|AF9015]] || [[DVB-T]] || {{Yes}} || Supports [[COFDM]]. A combo USB bridge & demod IC |
| [[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 |
| [[ATI/AMD]] || [[ATI/AMD Nxt2000|Nxt2000]] || [[ATSC]] || {{Unknown}} || Supports [[8-VSB]], [[QAM]]; firmware required |
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| [[Microtune]] || [[Microtune MT8872|MT8872]] || [[DVB-T]] || {{Unknown}} || [[COFDM]] |
| [[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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| [[Oren]] || [[Oren or51211|or51211]] || [[ATSC]] || {{Yes}} || supports [[8-VSB]] and [[QAM]]; firmware required, however, no QAM capable firmware is known |
| [[Oren]] || [[Oren or51211|or51211]] || [[ATSC]] || {{Yes}} || supports [[8-VSB]] and [[QAM]]; firmware required, however, no QAM capable firmware is known |
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| [[STMicroelectronics]] || [[STMicroelectronics STB0899|STB0899]] || [[DVB-S2]] || {{Yes}} || supports [[8PSK]], [[QPSK]], [[16APSK]] |
| [[STMicroelectronics]] || [[STMicroelectronics STB0899|STB0899]] || [[DVB-S2]] || {{Yes}} || supports [[8PSK]], [[QPSK]], [[16APSK]] |
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| [[STMicroelectronics]] || [[STMicroelectronics STV0900 |
| [[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]] |
| [[VLSI Technology]] || [[VLSI VES1893|VES1893]] || [[DVB-S]] || {{Yes}} || supports [[QPSK]] |
Revision as of 23:25, 26 November 2012
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 |
---|---|---|---|---|
Philips | TDA9887 | 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 ...