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40.2 Representative Terrestrial Digital Broadcasting Signals
ОглавлениеFor terrestrial broadcasting of digital TV programs, there are four major systems, and their worldwide geographic distribution is shown in Figure 40.1 [6, 35, 36]. In Europe, Australia, South Africa, India, and Southeast Asia, the standard is the DVB‐T (Digital Video Broadcasting – Terrestrial). An extension of DVB‐T, known as DVB‐T2, transmits compressed digital audio, video, and other data in “physical layer pipes” with a higher bit rate.
In the United States and South Korea, the standard is the American Television Standard Committee 8‐ary vestigial sideband modulation (ATSC‐8VSB), also known as ATSC 1.0. A next‐generation standard that leapfrogs to ATSC 3.0 will make use of advanced transmission and video/audio coding techniques to bring new and creative services to viewers. It is expected to hit the first 40 US television markets by the end of 2020.
In Japan and several South American countries, the DTV system is the ISDB‐T (Integrated Services Digital Broadcasting – Terrestrial). In China, including Hong Kong and Macao, and Cuba, the DTV standard is the DTMB (Digital Terrestrial Multimedia Broadcast). The DTMB contains both options for single‐carrier transmission (ATSC‐8VSB) and multi‐carrier transmission (TDS‐OFDM).
Corresponding to these terrestrial (T) versions, there are also versions for satellite transmission (S) and/or mobile and handheld (M/H) devices for the four standards, namely, DVB‐H/SH, ISDB‐S, and ATSC‐M/H. From the point of view of extracting TOA measurements without getting into the details of source and channel coding, bit error detection and correction, and data modulation and demodulation, we will review ATSC‐8VSB DTV signals in Section 40.2.1 and DVB‐T signals in Section 40.2.2, respectively, together with software receivers for acquisition and tracking. ISDB‐T, DTMB, and ATSC 3.0 are briefly presented in Sections 40.2.3, 40.2.4, and 40.2.5, respectively.