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Advanced Television Systems Committee (ATSC) 3.0, a recently developed terrestrial broadcasting standard, supports a Single Frequency Network (SFN), which extends service coverage and enhances received field strength without additional frequency resources. In SFN, multiple transmitters emit identical ATSC 3.0 broadcasting signals, which may cause constructive or destructive interference on a receiver side. The worst situation occurs when two signals from different transmitters are received with the opposite phase and similar power within a sample time, causing the cancellation of the received signal. In order to prevent such signal cancellation, ATSC 3.0 adopted transmitter diversity code filter sets (TDCFS), which is a frequency domain pre-distortion scheme to minimize cross-correlation among multiple transmitter signals in SFN. This paper sets up an ATSC 3.0 SFN consisting of two transmitter sites, transmitting high definition (HD) for mobile service and 4K ultra high definition (UHD) for fixed service. Layered division multiplexing (LDM) and time division multiplexing (TDM) are used to simulcast the two services with different robustness in the same radio frequency (RF) channel. Then, performance is evaluated using a threshold of visibility (ToV) and a successful reception rate. The time and frequency channel responses are changed at the same reception area when TDCFS is applied so the results show that reception performance is improved in the worst situation in SFN. [ABSTRACT FROM AUTHOR]

The robotic gripper is an essential component for handling, manipulating, and transporting objects. However, the parallel rigid gripper, which is one of the most widely used grippers in robotics, has limitations in handling fragile objects with a proper gripping force. We present a shape-adaptive universal soft gripper that can grip complex-shaped fragile objects with a high holding force. The shape-adaptive skin of the gripper has extremely low stiffness ($\sim$ 46 kPa), even lower than that of tofu ($\sim$ 57 kPa); hence, it can inherently prevent damage to the object. In addition, only the area pressed by the object is selectively deformed, so the contact surface of the gripper can be deformed to match the target object contour. A stiffness transition in the gripper from a soft to hard state follows to achieve effective holding of the object, not just weak object hanging as the previous soft gripper. These characteristics are enabled by a sheet-shaped shape retention layer, a honeycomb-shaped soft supporting layer, and a four-sided wall structure to increase shear modulus. We present applications to show the performance of the gripper, including gripping tofu, preparing a cocktail with a squeezed lemon, and whole chicken soup. [ABSTRACT FROM AUTHOR]

This article investigates the reliability gain of broadcast (BC)/broadband (BB) cooperation for mobile scalable video streaming. A specific form of BC-BB cooperation is introduced, which is referred to as cooperative casting. The proposed system primarily utilizes a BC transmission for streaming, while BB backup transmissions are requested whenever the BC signal is not decodable. For BC deliveries in this system, a cross-layer collaboration between scalable video coding (SVC) and layered-division multiplexing is used to improve spectral efficiency by coupling their hierarchical structures. In this end, in tandem with designing the uplink requesting rules based on channel status, delivery performance of the cooperative casting is analytically evaluated in a probabilistic framework. The system design and analyses presented in this article focus on the service continuity in a mobile and time-varying channel, where the physical aspects, such as delayed unicast response and inter-carrier interference, are carefully taken into account. Compared to the standalone network transmissions, the cooperative casting is numerically verified to better prevent the delivery failures in high-speed mobile channels, especially when the SVC layer-combined (full-scale video) service is intended. Furthermore, it is also shown that relaxing the criteria for the BB stream requesting can reduce delivery failures substantially, while it increases transmission redundancy. [ABSTRACT FROM AUTHOR]

To meet the ever increasing demand for better service quality and availability, the next generation digital TV (DTV) broadcast, a.k.a., the ATSC 3.0, is developed with new capabilities to deliver 4K ultra-high-definition (4K-UHD) services to fixed receivers, robust HD-quality services to mobile receivers, as well as non-broadcast services (e.g., broadband), including Internet of Things (IoT), Connected Vehicles, etc. To realize these capabilities, it becomes necessary to evolve the existing single-transmitter high-power-high-tower (HPHT) network to multi-transmitter low-power-low-tower single-frequency-networks (SFN), which requires installing new transmitters. Each new transmitter needs a feederlink to receive the service data from the broadcast gateway (BG) for transmission. This feederlink contributes to a significant portion of installation and operational costs of the new transmitters. This paper proposes a wireless in-band distribution link (WIDL) technology, where the distribution data is delivered to the newly deployed transmitters from the existing DTV towers wirelessly sharing the same TV band with the broadcast services. The distribution signal is multiplexed with service signal in the same ATSC 3.0 waveform. Layered division multiplexing (LDM) technology is proposed to achieve more efficient transmission of the distribution signal. The WIDL offers better performance and more robust operation than the on-channel repeater (OCR) technologies. More importantly, it offers the possibility of delivering backhaul data for future applications over the DTV infrastructure, such as IoT and connected vehicles. Therefore, the proposed WIDL is one enabling technology to achieve convergence of broadcast services with broadband and other wireless services on the DTV spectrum. [ABSTRACT FROM AUTHOR]

This paper analyzes reliability and quality gains that can be achieved by a broadcast-unicast convergent platform operating in non-orthogonal multiple access (NOMA)-based cellular networks. The analysis is addressed in network scope, dealing with randomly distributed users and base stations (BSs) within a stochastic geometry framework. Additionally a well-known Zipf-distribution popularity model on user demands is also taken into account, which effectively reflects a broadcasting gain from reducing redundant resource expense toward the users demanding same contents. Based on the stochastic modeling, closed-form delivery success probabilities and the consequent transmission rates are analytically derived, where the derivations are obtained separately for the networks with different access control strategies. Furthermore, the optimal broadcast content selection strategy maximizing the transmission rates is proposed. By means of numerical calculations, NOMA is shown to achieve substantial gain at broadcast/unicast joint transmission compared to the conventional orthogonal multiple access (OMA) network, particularly for the service configuration with popular contents having lower target service rates than less popular contents as long as the number of broadcast programs is restricted to be equal to the number of unicast services in a single frame. [ABSTRACT FROM AUTHOR]

This paper tackles a non-orthogonal multiplexing (NOM)-based realization of broadcast-unicast overlay transmission in cloud-radio access networks (C-RANs). In particular, fronthaul compression and precoding are jointly optimized to maximize the throughput in the considered network. The problem further optimizing the power allocation between broadcast and unicast signals is addressed as well. The algorithmic solutions are obtained by means of majorization minimization (MM)-type difference-of-convex (DC) programming. Moreover, the proposed solutions are further extended to cope with the uncertainty of channel state information (CSI) to enable robust transmission. Computer simulations are performed to verify that the proposed scheme attains substantial achievable rate gain over the conventional decentralized precoding in entire parameter regions considered. [ABSTRACT FROM AUTHOR]

This paper presents performance analysis of the Advanced Television Systems Committee (ATSC) 3.0 physical layer protocol in mobile multipath channels. Given the recommended configurations for ATSC 3.0 mobile services, intensive computer simulations as well as laboratory tests are conducted to verify the performance of various modulation and code combinations in ATSC 3.0 physical layer protocol. The results demonstrate that the ATSC 3.0 physical layer can reliably deliver intended mobile services in high-mobility scenarios. [ABSTRACT FROM AUTHOR]

The Fifth generation of mobile broadband (BB) networks, popularly known as 5G, aims to revolutionize different vertical industries, including media broadcasting. Although it remains to be seen the real impact and timescale of the 5G revolution, 5G may represent an opportunity rather than a threat for broadcast (BC), especially when considering new approaches for BC and BB evolving into new converged platforms inter-connecting terrestrial BC and cellular/wired BB systems together [item 1) in the Appendix]. Hybrid BC-BB platforms are already a success in several countries, based, e.g., on HbbTV in EU, hybridcast in Japan and Ginga in Brazil. But the increasing importance of fixed and mobile BB IP delivery for television services, well-illustrated by the new IP-based ATSC 3.0 standard [item 2) in the Appendix] and the on-going DVB-I (Internet) specification, and the fact that the 5G system will support and be interoperable with non-3GPP access technologies, potentially allowing multiple access technologies to be used simultaneously for one or more services, opens the door to new convergence scenarios. [ABSTRACT FROM AUTHOR]

This paper presents Internet protocol (IP)-based convergence of broadcast and broadband networks using Advanced Television Systems Committee (ATSC) 3.0–the next generation terrestrial broadcasting standard. In the broadcast network, the combination of Layered Division Multiplexing (LDM) and Scalable High Efficiency Video Codec (SHVC) is used, enabling efficient use of spectrum when mobile and fixed services are intended in a single radio frequency (RF) channel. The proposed use case of IP-based convergence is that a service is largely consumed through the high power high tower (HPHT) based broadcast network, and then alternative streams are requested via unicast for areas where broadcast signals are not receivable. The implementation details of broadcast and broadband convergence include MPEG Media Transport (MMT)/Real-time Objective delivery over Unidirectional Transport (ROUTE) description for broadcast useand Dynamic Adaptive Streaming over HTTP (DASH) for broadband use. To achieve seamless convergence between broadcast and broadband, transmission and reception systems based on ATSC 3.0 are hardware-developed and their implementation details are described. The proposed IP-based convergence use case of ATSC 3.0 broadcast and broadband is verified in a real-field environment using a public cellular network. [ABSTRACT FROM AUTHOR]

The development of 5G system provides a unique opportunity to implement a unified wireless transmission platform that can simultaneous deliver unicast, multicast and broadcast services using the same spectrum and the same infrastructure. This can be achieved by developing a more capable point-to-multipoint transmission (PTM) system component, also called 5G Multimedia Broadcast Multicast Services (5G-MBMS). A properly designed 5G-MBMS could achieve the convergence of terrestrial mobile broadband and TV broadcasting systems.By inherently allowing dynamic spectrum allocation among different types of services, this converged system could offer significant higher spectrum utilization. In this paper, the power-based non-orthogonal multiplexing (P-NOM) technology is proposed in addition to the existing orthogonal time-division-multiplexing (TDM) scheme. Significant capacity gains could be achieved by using P-NOM in a 5G-MBMS system for delivering different types of broadcast services, and for delivering mixed unicast and broadcast services. The capacity benefits of a 5G-MBMS with P-NOM is demonstrated by both theoretical analysis and computer simulations. A key finding is that using a two-layer P-NOM can essentially deliver a broadcast service on top of a unicast network, each achieving nearly full capacity. Next, a complexity analysis will reveal that implementing P-NOM in a 5G-MBMS system does not require significant additional complexity at consumer devices. Finally, it will be shown that, different from the non-orthogonal-multiple-access (NOMA) technologies, using P-NOM in 5G-MBMS system requires little or no change to the existing radio resource allocation mechanisms in LTE and 5G, when one power layer is used for broadcast services delivery. [ABSTRACT FROM AUTHOR]

Single frequency network (SFN) enables efficient use of spectrum by allocating the same frequency among multiple transmitters. In order to efficiently design and manage the SFN, the Advanced Television Systems Committee (ATSC) 3.0 physical layer standard has adopted transmitter identification (TxID) technology which allows to measure the individual and/or whole network channel response, such as power and time delay of the broadcast signal from transmitters. Since TxID is embedded into the host ATSC 3.0 frame as radio frequency (RF) watermark, it is transparent to legacy ATSC 3.0 receivers and only a specially designed TxID analyzer is able to detect it. This paper presents new TxID detection methods that improve the detection performance of ATSC 3.0 TxID signal by resolving the problems and limitation of the conventional TxID detection method. The superiorities of the proposed detection methods are verified through computer simulation, laboratory test, and field trial. [ABSTRACT FROM AUTHOR]

This paper proposes an improved decoding scheme of emergency alert wake-up bits in Advanced Television Systems Committee (ATSC) 3.0. When a broadcast service is being provided, a bootstrap signal of ATSC 3.0 includes the minimal essential information that does not change at least for two consecutive physical layer frames. Then, the received signal can be further assumed to be binary modulated according to each wake-up bit, so as to achieve the improved decoding performance as well as reduced decoding complexity. The simulation results show that the proposed decoding scheme of wake-up bits can obtain signal-to-noise ratio (SNR) gains of approximately 1.6 dB and 2.5 dB at bit error rate (BER) of 10−4 compared to the conventional decoding scheme under fixed and mobile reception environments, respectively. In addition, the analysis on the computational complexity of the proposed decoding scheme is provided. [ABSTRACT FROM AUTHOR]