Demodulator: Difference between revisions
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| [[Montage]] || [[Montage M88DS3000|M88DS3002]] || [[DVB-S2]] || {{Yes}} || [[QPSK]] [[8PSK]], [[16APSK]] and [[32APSK]] |
| [[Montage]] || [[Montage M88DS3000|M88DS3002]] || [[DVB-S2]] || {{Yes}} || [[QPSK]] [[8PSK]], [[16APSK]] and [[32APSK]] |
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| [[Montage]] || [[Montage M88DS3103|M88DS3103]] || [[DVB-S2]] || {{ |
| [[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 |
| [[Oren]] || [[Oren or51211|or51211]] || [[ATSC]] || {{Yes}} || supports [[8-VSB]] and [[QAM]]; firmware required, however, no QAM capable firmware is known |
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| [[Samsung]] || [[Samsung s5h1411|s5h1411]] || [[ATSC]] || {{Yes}} || Supports [[8-VSB]], [[QAM]]. |
| [[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 |
| [[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]] |
| [[SPaSE]] || [[SPaSE SP8870|SP8870]] || [[DVB-T]] || {{Unknown}} || supports [[COFDM]] |
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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 ...