Bo-Mi Lim

Low Complexity Layered Division Multiplexing for ATSC 3.0

In this paper, we propose novel transmitter and receiver architectures for low complexity layered division multiplexing (LDM) systems. The proposed transmitter architecture, which is adopted as a baseline technology of the Advanced Television Systems Committee 3.0, shares time and frequency interleavers, FFT, pilot patterns, guard interval, preamble, and bootstrap among different layers, so that the implementation of LDM receivers can be realized with less than 10% complexity increase compared to conventional single layer receivers. With such low complexity increment, we show simulation and laboratory test results that the proposed LDM system has significant performance advantage (3-9 dB) over traditional TDM systems, and maintains its performance up to the velocity of 260 km/h in mobile reception.

ATSC 3.0 Transmitter Identification Signals and Applications

In the ATSC 3.0 PHY layer standard, a transmitter identification (TxID) signal is defined in order to provide the identification of an ATSC 3.0 transmitter. TxID signal can also be used to find the co-channel and adjacent interference signals, to assist accurate location finding calculation, and to obtain the channel estimation for each transmitter, which can help local service (e.g., targeted advertisement) reception, as well as for emergency alert. For efficient use of spectrum and quality of service improvement, single frequency network (SFN) where all transmitters share a single RF channel is often implemented. The recently developed ATSC 3.0 physical layer standard has been designed to support SFN. For efficient designing, fine-tuning and operating an SFN, it is crucial to identify each transmitter, as well as to adjust transmitting power and emission time of each transmitter. This paper presents TxID for ATSC 3.0, and analyzes its detection performance under very low signal to noise ratio environments and other applications, such as location finding, and channel estimation etc. for each SFN transmitter.

ATSC 3.0 LDM-based mobile performance under HPHT metropolitan environment

This paper presents field test result of an LDM-based mobile broadcasting system, and analyze the results based on reception power (or field strength) and erroneous second ratio (ESR).

Multiple Service Configurations Based on Layered Division Multiplexing

In this paper, we present multiple service configurations based on layered division multiplexing (LDM), which is adopted as a baseline technology of the Advanced Television Systems Committee 3.0 standard. Based on a two-layer LDM technology, a variety of multiple-physical layer pipe (PLP) configurations as well as physical layer framing is introduced depending on the choices of service scenario, time interleaving, and cell addressing. A performance analysis is provided when three different broadcasting services—robust audio, indoor/mobile, and high data rate services—are delivered through different PLPs when a number of broadcasting service scenarios is presented.

Field Test Results of Layered Division Multiplexing for the Next Generation DTV System

In this paper, we present field test results of a layered division multiplexing (LDM) technology for the next generation digital television system, and analyze the results in several scenarios such as rooftop, indoor, and mobile receptions. In order to evaluate performance of the LDM technology, the field strength or the reception power is measured for all considered scenarios. Furthermore, the threshold of visibility, the marginal reception power, and the erroneous second ratio are measured for fixed, indoor, and mobile receptions, respectively. The field test results show that LDM technology enables broadcaster not only to efficiently provide a variety of services (e.g., mobile, indoor, and stationary services) with different robustness within a single radio frequency (RF) channel but also to increase flexible usage of the RF channel.

Performance evaluation of multiple-PLP based LDM systems for the next generation terrestrial broadcasting

In this paper, we present performance evaluation of multiple physical layer pipe (PLP) based layered division multiplexing (LDM) systems for the next generation terrestrial broadcasting. In addition to a conventional multiple-PLP configuration, which is based on time division multiplexing (TDM), a variety of LDM configurations, which includes combinations of TDM and two-layer LDM, and three-layer LDM, are considered. Given three different broadcasting contents are delivered by three PLPs, performance comparison and analysis are provided when four different multiple-PLP configurations including TDM, two-layer LDM, and three-layer LDM are used.

Field Comparison Tests of LDM and TDM in ATSC 3.0

In this paper, we present laboratory and field test results of layered division multiplexing (LDM) and time division multiplexing (TDM) technologies based on Advanced Television Systems Committee 3.0. The presented field test results include analysis in several scenarios such as rooftop, indoor, and mobile receptions. In order to provide performance comparison of the LDM and TDM technologies, reception power (field strength) and successful reception rate are measured for all the considered scenarios. For in-depth analysis in real field environment, further field measurements such as threshold of visibility, marginal (minimal) reception power, and erroneous second ratio are used for rooftop, indoor, and mobile receptions, respectively. The laboratory and field test results show that the LDM technology not only shows superior performance compared to the TDM technology in all the considered scenarios (rooftop, indoor, and mobile receptions), but also enables broadcaster to efficiently provide a variety of services (e.g., mobile, pedestrian, indoor, and stationary services) with different robustness within a single radio frequency channel.

Efficient Transmission of Multiple Broadcasting Services Using LDM and SHVC

In this paper, we present an efficient transmission method of multiple broadcasting services using layered division multiplexing (LDM) and scalable high efficiency video coding (SHVC) based on the next generation terrestrial digital broadcasting standard, advanced television systems committee 3.0. In a two-layer LDM system, each layer forms a physical layer pipe that carries base layer and enhancement layer video streams of SHVC, respectively. This combination of physical and presentation layers technologies can maximize channel utilization when multiple broadcasting services are delivered in a single radio frequency channel with different robustness and reception conditions. An intensive performance analysis is provided when the proposed combination of LDM and SHVC is compared with other approaches, such as time division multiplexing and/or high efficiency video coding simulcast broadcasting. Several performance measurements are also introduced, such as constant data rate measurement and constant quality measurement, which are used to evaluate the performance of video codecs in conjunction with different physical layer system parameters. A prototype hardware system with LDM and SHVC capable of selecting different parameter combinations is tested in the laboratory and in real field environments to verify the performance and feasibility of the proposed LDM and SHVC combination. Results show that the proposed LDM and SHVC combination provides significant gains on video service quality as well as reception robustness.

Scalable HEVC over layered division multiplexing for the next generation terrestrial broadcasting

In this paper, we present an efficient transmission method of multiple broadcasting services using Layered Division Multiplexing (LDM) and Scalable High Efficiency Video Coding (SHVC) for the next generation terrestrial digital broadcasting such as Advanced Television Systems Committee (ATSC) 3.0. Based on a two-layer LDM technology, each Physical Layer Pipe (PLP) carries each of Base Layer and Enhancement Layer video streams of SHVC, in order to maximize channel utilization when multiple broadcasting services are delivered in a single radio frequency (RF) channel. A performance analysis is conducted when the proposed combination of LDM and SHVC is compared with other combinations such as Time Division Multiplexing (TDM) and/or HEVC simulcast broadcasting. A constant quality measurement is introduced to evaluate the performance of video codec in conjunction with a physical layer system. The proposed combination of LDM and SHVC is implemented in hardware and verified in a real field environment.

Transmitter identification for ATSC 3.0 single frequency network

In the ATSC 3.0 PHY layer standard, a Transmitter Identification (TxID) signal is defined in order to provide the identification of an ATSC 3.0 transmitter. For efficient use of spectrum and quality of service improvement, single frequency network (SFN) where all transmitters share a single RF channel is often implemented. The recently developed ATSC 3.0 physical layer standard has been designed to support SFN. For efficient designing, fine-tuning and operating an SFN, it is crucial to identify each transmitter, as well as to adjust transmitting power and emission time of each transmitter. This paper presents TxID for ATSC 3.0, and analyzes its detection performance under very low signal to noise ratio (SNR) environments.