镇压
发表于 2025-3-28 18:37:51
A Comparison of Digital Video Standards, that of VHS at CD data rates (< 1.5 Mbit/s). MPEG-1 was provided only for applications on storage media (CD, hard disk) and not for transmission (broadcasting) and its data structures correspond to this objective. The audio and video coding of MPEG-1 is quite close to that of MPEG-2 and all the fun
入会
发表于 2025-3-28 21:48:00
Measurements on the MPEG-2 Transport Stream,a large need for test instruments for digital television, but of a different type. Where it was mainly video analyzers for evaluating the test lines of an analog baseband signal in analog television, it is mainly MPEG-2 test decoders which are being used in digital TV. Throughout the world, taking m
CROW
发表于 2025-3-29 01:31:15
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漂泊
发表于 2025-3-29 03:49:04
Basic Principles of Digital Modulation,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
AVANT
发表于 2025-3-29 08:31:15
,Transmitting Digital Television Signals by Satellite — DVB-S/S2,n Europe, a simple satellite receiving system complete with dish, LNB and receiver is available for less than 100 Euros and there are no follow-up expenses. Similar importance must, therefore, be accorded to the distribution of digital TV signals over the same transmission path. In the meantime, ana
轻快走过
发表于 2025-3-29 12:15:54
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. Satellite transmission is relatively rugged and, in principle, only subject to noise effec
显赫的人
发表于 2025-3-29 18:27:45
Broadband Cable Transmission According to DVB-C,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 complexitie
巫婆
发表于 2025-3-29 21:07:40
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 64QAM and 256QAM with a roll-off factor of r = 0.18 (64QAM) and r = 0.12 (256QAM). The error protection
江湖骗子
发表于 2025-3-30 01:27:44
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 256QAM, 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 an
令人发腻
发表于 2025-3-30 06:31:37
Coded Orthogonal Frequency Division Multiplex (COFDM),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