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Partial Responses and Single-Sideband Optical Modulation
Published in Le Nguyen Binh, Advanced Digital, 2017
The effect of VSB filtering on the Q factor and its dispersion tolerance can be examined by varying the passband characteristic of the VSB filter and measuring the Q factor for each lightwave channel at the output of the demultiplexer, as shown in Figure 10.59. It is clear that, for the 40 Gbps NRZ data format, the system penalty is one unit of the Q factor, which is equivalent to one decade of BER or about 10 dBQ when the passband of the OF is extended from 20 to 24 GHz. This penalty could be due to the cutoff of the signal band by the roll-off band of the OF with more than half of the bandwidth eliminated. For 28 GHz passband, the Q factor increases considerably to 7.8, or BER = 10−15—that is, error-free transmission when the sampling is at the center of the eye. This shows that the performance of the VSB modulation format is better than double-sideband (DSB) modulation, since the VSB format eliminates most but not all of the redundant sideband.
Transmission of 160-Gb/s Modified Manchester modulation over WDM system
Published in International Journal of Electronics, 2019
Festus Idowu Oluwajobi, Dong-Nhat Nguyen, Amin Malekmohammadi
Therefore, recently the Modified Manchester (MM) modulation format was proposed as a new modulation technique, which is originated after the amalgamation of Manchester plus Vestigial-Sideband (VSB) techniques (Idowu Oluwajobi, Dong-Nhat, & Malekmohammadi, 2018). The MM modulation has smaller spectral width due to the use of VSB (Idowu Oluwajobi et al., 2018) and VSB technique is an effective scheme to enhance the spectral efficiencies of WDM systems in high-speed optical transmission link (Lu et al., 2011; Xu, Yu, Lu, Qu, & Deng, 2015). Since MM signal has a compact spectrum in comparison with conventional Manchester therefore has better spectral efficiency, which is expected to increase the capacity of the WDM channels greatly.
The Changing Face of Public Broadcasting in India
Published in IETE Journal of Education, 2023
Cable TV came to India side by side with the satellite TV. In the case of cable TV, analog channels employed vestigial sideband (VSB) modulation for the baseband as in the case of terrestrial analog TV. The RF carriers in the range of 40–600 MHz, similar to those used for terrestrial analog TV broadcasting, were assigned to different channels of cable TV. The signals were compatible with the VSB signals used for terrestrial analog TV.
Development of 3DTV Emission Multiplexer and Reception-Signal Status Analyzer for ATSC 8-VSB & MDTV Hybrid 3DTV Services
Published in IETE Journal of Research, 2020
Sung-Hoon Kim, Dong-Wook Kang, Kyeong-Hoon Jung, Ki-Doo Kim
Advanced Television Systems Committee 8-vestigial side-band (ATSC 8-VSB) and ATSC mobile digital television (MDTV) standards (ATSC A/53 and A/153) are currently being adopted in terrestrial fixed high-definition television (HDTV) and MDTV broadcasting systems in North America and Mexico [1,2]. The 8-VSB and MDTV standards provide a fixed HDTV and mobile TV service by sharing a 6-MHz RF channel. However, adding HD quality to a three-dimensional television (3DTV) service within the same RF channel is hindered by lack of spectrum space. Table 1 shows examples of frequency allocation to HDTV, SDTV, mobile TV, and 3DTV services [3,4]. In this service scenario, the bit-rate allocations of standard definition television (SDTV) and mobile services are fixed at 4.7 Mbps and 3 Mbps, respectively. This scenario is heavily constrained by the total available bandwidth (6-MHz). To support fixed HDTV, mobile, and high-quality 3DTV services, broadcasters require a much greater transmission bandwidth [5]. To overcome these spectrum bandwidth constraints, ATSC has adopted a fixed and mobile TV hybrid 3DTV system (A/104 part 5, SC-MMH) as a standard for a 3DTV service [6]. This service compatible-main and mobile hybrid (SC-MMH) system simultaneously transmits MPEG-2 video (left-eye images) through an HD main fixed TV channel (8-VSB), and H.264 video (right-eye images) through a mobile channel (MDTV) [7]. Consequently, the SC-MMH 3DTV system can provide HDTV, mobile DTV, and 3DTV services within a single RF channel. The proposed SC-MMH 3DTV system supports stereoscopic 3D HD quality services, by mixing left/right-eye images for 3D image rendering. To provide more comfortable 3D services incorporating human factors, this system also supports enhanced video processing technologies with a small amount of disparity map information (Video Enhancement Information or VEI). The SC-MMH 3DTV system requires 8-VSB and MDTV frame synchronization, and a 3D service descriptor insertion at the transmission side. This is different from existing 2D service systems. The SC-MMH 3DTV will receive both 8-VSB and MDTV signals simultaneously. Figure 1 shows the service overview of the SC-MMH 3DTV system. For a seamless SC-MMH 3D service providing, broadcasters should slightly modify the legacy-service compatible 3D encoder, transmitter and measuring RFs of both 8-VSB and MDTV signals to analyze service available area. In this paper, since the 3D video and VEI encoders are beyond the scope, we consider only the delivery/transmission of the SC-MMH 3D contents. We also introduce the implementation and field test of SC-MMH emission multiplexer and reception-signal status analyzer for an efficient service system configuration.