interior
发表于 2025-3-28 16:02:24
Digital Modulation Basics,e possible to continue e.g. in the field of mobile radio technology (GSM, IS95 or UMTS) as the basic knowledge discussed here applies to the field of communication technology and its applications overall. However, its prime intent is to create the foundation for the subsequent chapters on DVB-S, DVB
高脚酒杯
发表于 2025-3-28 19:03:23
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ironic
发表于 2025-3-29 00:13:14
DVB-S Measuring Technology,he DVB Measurement Guidelines ETR290 also contain a relatively small chapter on DVB-S measuring technology. In comparison with DVBC and DVB-T measuring technology, the discussion will be relatively brief here.
dragon
发表于 2025-3-29 03:09:34
Broadband Cable Transmission of Digital TV Signal (DVB-C), a bandwidth of about 400 MHz (approx. 50 – 450 MHz) or about 800 MHz (approx. 50 – 860 MHz). In addition to the VHF and UHF band known from terrestrial television, special channels are occupied. Analog television programs can be received easily with a conventional TV set without additional complexi
artless
发表于 2025-3-29 08:05:18
Broadband Cable Transmission According to ITU-T J83B,parable to J83A, C (Europe, Japan) but there are great differences in detail, especially in the FEC. The channel bandwidth in J83B is 6 MHz as in J83C (Japan). The modulation methods used are only 64 QAM and 256 QAM with a roll-off factor of r = 0.18 (64 QAM) and r = 0.12 (256 QAM). The error protec
CHART
发表于 2025-3-29 12:22:02
Measuring Digital TV Signals in the Broadband Cable,oadband cable testing and is also necessary. The influences acting on the broadband cable signal, which can be modulated with up to 256 QAM, are more varied by far, and more critical than in the satellite domain. In this section, the test instruments and measuring methods for measurements on DVB-C a
两栖动物
发表于 2025-3-29 18:28:39
Orthogonal Frequency Division Multiplex (OFDM),mation. The message to be transmitted is impressed on a sinusoidal carrier by applying analog amplitude, frequency or phase modulation techniques. Since the eighties, single-carrier transmission is more and more by digital methods in the form of frequency shift keying (FSK) and in many cases also by
背带
发表于 2025-3-29 21:16:40
The Terrestrial Transmission of Digital Television Signals (DVB-T),on Multiplex). They are mainly determined by multipath reception which leads to location- and frequency-selective fading. In DVB-T, i.e. in the terrestrial transmission of digital TV signals according to the Digital Video Broadcasting standard, it was decided that the most appropriate modulation met
adj忧郁的
发表于 2025-3-30 00:29:25
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sacrum
发表于 2025-3-30 05:59:32
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