Digital Terrestrial Television Broadcasting Research Articles

Land Clutter Statistics From an Airborne Passive Bistatic Radar

Passive operation is an important operational concept for future airborne radar platforms. Successful target detection requires an understanding of the underlying clutter statistics in order to set the detection threshold accurately. In addition, clutter statistics are important for modeling of passive radar performance and simulation of passive bistatic radar to aid in the development of new target detection algorithms. In this article, the clutter statistics of data from an airborne platform are studied over a range of bistatic geometries and receive polarizations. The illuminator is a digital video broadcast-terrestrial (DVB-T) station and the collected data spans both ground and maritime regions. The key contributions include a study of amplitude statistics using a number of common distributions and understanding the impact of the reference signal quality in terms of the clutter statistics.

Jamming Effects on Hybrid Multistatic Radar Network Range and Velocity Estimation Errors

This research studies the effects of three noise jamming techniques on the performance of a hybrid multistatic radar network in a selection of different electronic warfare (EW) situations. The performance metrics investigated are the range and velocity estimation errors found using the Cramér-Rao lower bounds (CRLBs). The hybrid multistatic network simulated is comprised of a single active radar transmitter, three illuminators of opportunity (IO), a receiver co-located at the active transmitter site, and two separately located silent receivers. Each IO transmits at a unique frequency band commonly used for civilian applications, including Digital Video Broadcasting-Terrestrial (DVB-T), Digital Audio Broadcasting (DAB), and FM radio. Each receiver is capable of receiving signals at all three IO frequency bands as well as the operating frequency band of the active radar transmitter. The investigations included compare the performance of the network at detecting a single airborne target under conditions where different combinations of jammer type, operating mode, directivity, and number of operating jammers are used. The performance degradation of the system compared to operation in a non-contested environment is determined and a comparison between the performance of the hybrid multistatic radar with that achievable by a monostatic radar and an active-only multistatic radar network within a selection of contested scenarios is made. Results show that the use of spatially distributed nodes and frequency diversity within the system enable greater theoretical functionality in the presence of jamming over conventional radar systems.

Quantization Algorithms in Healthcare Information Telematics Using Wireless Interactive Services of Digital Video Broadcasting

Background: In the new era of wireless communications new challenges emerge including the provision of various services over the digital television network. In particular, such services become more important when referring to the tele-medical applications through terrestrial Digital Video Broadcasting (DVB). Objective: One of the most significant aspects of video broadcasting is the quality and information content of data. Towards that end several algorithms have been proposed for image processing in order to achieve the most convenient data compression. Methods: Given that medical video and data are highly demanding in terms of resources it is imperative to find methods and algorithms that will facilitate medical data transmission with ordinary infrastructure such as DVB. Results: In the present work we have utilized a quantization algorithm for data compression and we have attempted to transform video signal in such a way that would transmit information and data with a minimum loss in quality and succeed a near maximum End-user approval. Conclusions: Such approaches are proven to be of great significance in emergency handling situations, which also include health care and emergency care applications.

Bistatic Forward ISAR with DVB-T Transmitter of Opportunity.

The radar geometry defined by a spatially separated transmitter and receiver with a moving object crossing the baseline is considered as a Bistatic Forward Inverse Synthetic Aperture Radar (BFISAR). As a transmitter of opportunity, a Digital Video Broadcast-Terrestrial (DVB-T) television station emitting DVB-T waveforms was used. A system of vector equations describing the kinematics of the object was derived. A mathematical model of a BFISAR signal received after the reflection of DVB-T waveforms from the moving object was described. An algorithm for extraction of the object’s image including phase correction and two Fourier transformations applied over the received BFISAR signal—in the range and azimuth directions—was created. To prove the correctness of mathematical models of the object geometry, waveforms and signals, and the image extraction procedure, graphical results of simulation numerical experiments were provided.

Field Trials of UHDTV Broadcasting over DTMB-A System

<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Digital terrestrial television broadcasting (DTTB), the most fundamental infrastructure for audio/video transmission networks, can support multimedia information services, targeting lots of audiences within a wide area in an efficient way. The advanced version of digital television/terrestrial multimedia broadcasting (DTMB-A), one of the second-generation DTTB standards of the International Telecommunication Union, provides higher spectrum efficiency and better transmission reliability compared with DTMB. By adopting a more flexible frame structure, advanced forward error correction coding, and improved constellation mapping, it is confirmed that the transmission capacity of DTMB-A is around 30% higher than that of DTMB under the same conditions carried out in laboratory tests and field trials on DTMB-A. In this paper, the trial network and the measurement results focusing on ultrahigh-definition television (UHDTV, both UHD-1/4K and UHD-2/8K) and the single-frequency network (SFN) are presented in detail. The preliminary work on the Integrated Communications and Broadcasting Network (ICBN) concept using both DTMB-A and fifth-generation (5G) networks for UHDTV delivery is also highlighted</i> .

A Novel Coordinated Multipoint Scheme With Zero Guard Interval for ATSC 3.0 Single Frequency Networks

Advanced Television Systems Committee (ATSC) has issued ATSC 3.0 as the standard for the next-generation of Digital Terrestrial Television (DTT) broadcasting. ATSC 3.0 introduces several new features including Layered Division Multiplexing (LDM) that is a form of Non-Orthogonal Multiple Access (NOMA). ATSC 3.0 supports the legacy Single Frequency Networks (SFN), where the Guard Interval (GI) is considered to overcome the multipath as well as the asynchronous reception from different transmitters. Considering the huge distances between the DTT broadcasters, the GI overhead could be comparable to the data size, making the control/data ratio unfavorable. This paper proposes the association of Coordinated MultiPoint (CoMP) in SFN with NOMA-LDM. A novel formation of the channel matrix is provided that jointly includes the asynchronous channel's cross correlations for further joint detection of the signals at the receiver. The purpose is to enhance the coverage and spectral efficiency while avoiding hectic guard intervals or directional antennas. The capacity region is derived in an information theoretic framework based on exploiting the asynchronous channels' memory and correlation. We show that the spectral efficiency can exceed that of the non-coordinating schemes, provided that the proper receiver is equipped with the proposed channel matrix formation. Our extensive simulations validate that our proposed association of CoMP-SFN with NOMA-LDM provides a considerable boost in the coverage and channel reliability, while increasing the spectral and power efficiency.

Analysis and Estimation of the Field Strength of Digital Terrestrial Television Broadcasting

DVB-T is the most widely used standard for digital television broadcast. With its introduction in 1997, it is used in more than 70 countries. Almost all of these countries adopted the new standard for digital terrestrial television broadcasting – DVB-T2. DVB-T2 is the best technology for digital television broadcasting, which offers better signal robustness, flexibility and more than 50% more efficiency, compared with other digital terrestrial television broadcast systems. This paper focuses on ways to deliver MPEG TS to transmitters and estimation of the field strength.

Impact of GPS Interference on Time Synchronization of DVB-T Transmitters

Nowadays, the Global Positioning System (GPS) is widely used in all aspects of our lives. GPS signals are not used only in positioning and navigation applications and services in transport and military, but, thanks to quite precise information about time, also for synchronization of world trade and synchronization of wireless transmitters. However, with the recent spread of location-based services, a large number of GPS jammers had appeared. Use of these jammers is prohibited by law; however, their use is gaining popularity especially in the transport segment since jammers can be used to trick vehicle onboard units and help avoid paying toll fees on highways or avoid tracking of company cars when used privately. In this paper, we will investigate the impact of GPS interference caused by jamming and spoofing on the synchronization of Single Frequency Network (SFN) Digital Video Broadcasting–Terrestrial (DVB-T) transmitters. Since GPS signals are used in the DVB-T SFN to provide synchronization which is crucial for the correct network operation, the interference of GPS signals can cause problems with signal distribution. Thus, signals received from a DVB-T SFN network might be out of synchronization and disrupt the service for users.

Review on 5G NR LDPC Code: Recommendations for DTTB System

The freezing of the 5th generation new radio (5G NR) Release 16 indicates that 5G development has stepped into a new stage. The application of a dedicated low-density parity-check (LDPC) code for channel coding is an important technical advance that distinguishes 5G NR from the 4th generation (4G) long-term evolution (LTE) and LTE-advanced. Although LDPC codes has been used in many different systems, the newly developed LDPC code in 5G NR integrates many cutting-edge technologies to provide better performance and attractive features. Thus, it can be a good reference for channel coding in other evolving systems headed by digital terrestrial television broadcasting (DTTB). In emerging applications, the DTTB system needs to carry information with higher density, while meeting the high requirements for real-time, coverage, and bit error rate of broadcasting. To provide a reference for DTTB channel coding that improves its performance and supports new services, a review of 5G NR LDPC code implementation is carried out from three aspects: code analysis and design, decoding algorithm, and decoder architecture. We thoroughly evaluate each solution and highlight some candidates for existing implementations or some directions for further development of the DTTB system.

IMPLEMENTATION OF FPGA-BASED DVB-T2 TRANSMITTER FOR A SECOND GENERATION DIGITAL TERRESTRIAL TELEVISION BROADCASTING SYSTEM

Nowadays, with strong development of Science and Technology, integrated circuits continue to dominate not only in the field of digital information. Over the last several years, Technological television industry has taken huge strides and powerful transformation to meet with government’s policy about digitization of television all over the country in period 2015 – 2020. Stemming from the practical needs of “localization of products” and mastering of technological design of DVB-T2 transmitter (Digital Video Broadcasting – Terrestrial for Second generation), the authors have made an effort to research in algorithm, designed and tested in Field Programmable Gate Array (FPGA) technology. DVB-T2 is mainly aimed to replace the current standard DVB-T. The main motivation of DVB-T2 is to provide broadcasters with more advanced and efficient alternative to DVB-T standards. In DVB-T2 transmitter system, digital audio, video, and other data are compressed into a single signal to be transmitted on a single RF channel, using orthogonal frequency-division multiplexing (OFDM) with concatenated channel coding and interleaving. The higher offered bit rate makes it a suited system for carrying HDTV signals on the terrestrial TV channel. The next generation broadcasting systems should be designed to make full use of spectral resources while providing reliable transmissions in order to enable services like multichannel HDTV (High Definition Television) and innovative data casting services. The efficient usage of the radio spectrum can be achieved by the introduction of Single Frequency Networks (SFN). Digital transmitter DVB-T2 implemented on FPGA using a software Xilinx System Generator for DSP tool and Xilinx ISE Design Suite 14.7. System Generator for DSP is in conjunction on environment MATLAB-Simulink that is capable of simulating the proposed hardware structures that is synthesized and implemented by the programmable elements in Field-programmable Gate Arrays. In this project, adaptative MPEG-TS bitrate converter is designed to allows to increasing or reducing the MPEG TS rate by adding or filtering NULL packets. The entire digital transmitter DVB-T2 is integrated in one chip Xilinx FPGA Kintex-7 XC7K325T-1FFG676. Experimental design on development Kit NetFPGA-1G-CML of Digilent Corporation is performed at design department of technology center of Vietnamese Communications Television Development JSC. Authors are continuing to improve products, put into practical applications to replace the digital terrestrial television broadcasting stations that are being used in Vietnam. The article named “Implementation of FPGA-based DVB-T2 transmitter for a second generation digital terrestrial television broadcasting system” presents the research results, design methods, test results to compare, evaluate the accuracy of algorithm implementation. The results open up new directions for technological television in Vietnam.

Compressed Sensing‐Based Range‐Doppler Processing Method for Passive Radar

Passive radar (PR) systems use the existing transmitters of opportunity in the environment to perform tasks such as detection, tracking, and imaging. The classical cross‐correlation based methods to obtain the range‐Doppler map have the problems of high sidelobe and limited resolution due to the influence of signal bandwidth. In this paper, we propose a novel range‐Doppler processing method based on compressed sensing (CS), which performs sparse reconstruction in range and Doppler dimensions to achieve high resolution and reduces sidelobe without excessive computational burden. Results from numerical simulations and experimental measurements recorded with the Chinese standard digital television terrestrial broadcasting (DTTB) based PR show that the proposed method successfully handles the range‐Doppler map formatting problem for PR and outperforms the existing CS‐based PR processing methods.

3D Target Localization by Using Particle Filter with Passive Radar Having one Non-cooperative Transmitter and one Receiver

In a passive radar system, localizing a target in Cartesian space is achieved by using one of the following bistatic geometries: multiple non-cooperative transmitters with one receiver, one non-cooperative transmitter with multiple receivers, or one non-cooperative transmitter with one receiver. In this paper, we propose a new method for localizing a target in Cartesian space by passive radar having the bistatic geometry “one non-cooperative transmitter and one receiver”. This method depends on using two consecutive particle filters for estimating and analyzing the Doppler frequency and time delay of the target’s echo signal. The theoretical analysis of the proposed method is presented, and its efficiency is verified by simulating the passive radar system with a Digital Video Broadcasting-Terrestrial (DVB-T) transmitter.

EFFICIENT IMPLEMENTATION OF FPGA-BASED FORWARD ERROR CORRECTING COMBINATION AND BIT TO CELL WORD DE-MULTIPLEXER FOR A SECOND GENERATION DIGITAL TERRESTRIAL TELEVISION BROADCASTING SYSTEM

This article focus on the implementation of FEC part. The motivation of the design is that FEC is an effective tool to mitigate problems associated with OFDM which stem from multipath fading channel, high speed data rate. One of the key features of BCH codes is that during code design, there is a precise control over the number of symbol errors that are correctable by the code. BCH coder proccesses parralelly with high-speed operation. 8-bit parallel data input and output helps to maximize the throughput. DVB-T2 used LDPC coder, as inner codes with word length up to 64,800 bits, enabling significant proximity to Shannon limit. This encoder supports all code rates and both normal and short frames. Output of LDPC encoder is interleaved with bit interleaver. This project was fully optimized for speed and memory area, fully synchronized by using a single clock. The design was coded in VHDL, synthesized by using Xilinx ISE Design Suite 14.7. The design has been tested on development Kit NetFPGA-1G-CML of Digilent Corporation and the bit map was downloaded into Xilinx Kintex-7 XC7K325T-1FFG676, which is integrated on experimental transmitter system DVB-T2. This research product belong to program “Research of experimental testing of second generation digital terrestrial television broadcasting system DVB-T2” of Vietnamese Communications Television Development JSC.

Single section, octave bandwidth, high‐power combiner in the UHF band

In this work, a planar broadband high-power combiner in the ultra-high-frequency band (UHF) is presented. The proposed broadband combiner is a modified version of the conventional Wilkinson power combiner. The isolation resistor of 100 Ω in the conventional Wilkinson combiner is replaced by two 50 Ω terminating resistors. Two overlay couplers transform the terminating resistors to a floating resistor between the input branches. Terminating resistors are preferred to a floating resistor because of higher power handling and lower parasitics. Even- and odd-mode method is employed for the analysis. The design goal is 20 dB isolation and ports return loss in an octave bandwidth. To verify the design concept, a high-power combiner in the frequency range of 470 to 860 MHz used for digital video broadcasting-terrestrial (DVB-T) applications is designed and constructed. Full-wave simulations are compared with measurements. The fabricated power combiner handles 400 W output power. Analytical formulations presented in this work are not restricted to UHF band and can be used to design an octave bandwidth combiner in other frequency bands.

DVB-T-Based Passive Forward Scatter Radar: Inherent Limitations and Enabling Solutions

This article investigates the target detection capability of a passive forward scatter radar (PFSR) exploiting a digital video broadcasting - terrestrial (DVB-T) transmitter as illuminator of opportunity. By means of theoretical and simulated analyses, it is shown that conventional processing schemes might suffer from significant performance degradation when exploiting orthogonal frequency division multiplexing (OFDM) waveforms of opportunity compared to other broadcast transmissions (e.g., frequency modulation radio broadcast). Specifically, the direct application of conventional processing approaches to the case of a DVB-T PFSR is demonstrated to yield: 1) a nonnegligible increase of the competing background level and 2) a steeper fading of the target response due to the intrinsic characteristics of the exploited waveforms of opportunity, above all the modulation scheme and the signal spectral characteristics. Therefore, appropriate signal processing techniques are proposed to avoid these effects which jeopardize the target detection capability. The conceived processing scheme exploits the digital nature of the employed waveforms and a subband approach for improving both the interference cancellation stage and the target signature extraction. The benefits of the proposed approach are illustrated by means of theoretical and simulated analyses. The application of the resulting processing scheme against experimental data proves its effectiveness in practical scenarios.

Doppler Frequency Estimation for a Maneuvering Target Being Tracked by Passive Radar Using Particle Filter

In this paper, we estimate Doppler frequency of a maneuvering target being tracked by passive radar using two types of particle filter, the first is “Maximum Likelihood Particle Filter” (MLPF) and the second is “Minimum Variance Particle filter” (MVPF). By simulating the passive radar system that has the bistatic geometry “Digital Video Broadcasting-Terrestrial (DVB-T) transmitter / receiver” with these two types, we can estimate the Doppler frequency of the maneuvering target and compare the simulation results for deciding which type gives better performance.

Compact Ultra-Wide-Band HI Monopole Antenna Loaded with C-Shaped Parasitic Elements for DVB-T and LTE Applications

In this study, a compact ultra-wide band microstrip antenna loaded with C-shaped parasitic elements, for Digital Video Broadcasting – Terrestrial (DVB-T) and LTE 450 / 700 signal reception, is presented. The proposed antenna is named “HI Monopole”, and its geometry has been designed to be simple and intuitive, lightweight, compact, possessing a low fabrication cost as well as an easy installation process inside electronic gadgets. The HI Monopole operates with ultra-wide bandwidth characteristics for operation within Digital Video Broadcasting – Terrestrial (DVB-T) standard, 470–890 MHz, that has been accomplished by: inserting an indent in its ground plane, adjusting the dimension of the feeding line, and adding two C-shaped parasite elements onto the region posterior to the antenna’s main irradiating element. It was verified through electromagnetic measuring that this device is capable of covering the 429-1022 MHz range, thus having 593 MHz of bandwidth. The superior and inferior cutoff frequencies have been chosen as the values in –10 dB of the device’s return loss. Therefore, the proposed antenna can be utilized in DTV and LTE signal reception through broadcasting in any country, independently of its adopted standard.

TDS-OFDM based Digital Television Terrestrial Multimedia Broadcasting Standards

As the most popularly utilized broadcasting network, digital terrestrial television broadcasting (DTTB) can provide multimedia information coverage for the broad audience in a very efficient way because of its characteristic of wide-range coverage and mobile reception ability. After promulgating the first generation DTTB standard, digital terrestrial/television multimedia broadcasting (DTMB), in 2006, China began to research and develop the next generation DTTB standard, namely DTMB-advanced (DTMB-A), aiming to support higher spectrum efficiency and further improve transmission reliability. In 2019, DTMB-A was accepted by ITU as the second generation international DTTB standard (as System C). Similar to DTMB, time-domain synchronous - orthogonal frequency division multiplexing (TDS-OFDM) based multi-carrier modulation scheme is adopted by DTMB-A. Thanks to the more flexible frame structure, advanced error correction coding and improved constellation mapping, DTMB-A offers 30% higher transmission capacity than DTMB under the same transmission conditions. Thus, DTMB-A can support both fixed and mobile reception more efficiently, and provide users with higher quality services such as ultra-high definition television (UHDTV). This paper first gives details of key technologies at the transmitter of DTMB/DTMB-A and introduce core algorithms at the receiver. Both laboratory test and field trial results will then be provided and analyzed, especially for the application of 4K UHDTV and single frequency network (SFN).

EFFECT OF SOME RADIO CLIMATIC FACTORS ON DIGITAL TERRESTRIAL TELEVISION SIGNAL IN A SAHEL SAVANNAH CITY OF NIGERIA

This study investigates the effect of some radio climatic factors on the Received Signal Strength (RSS) of a Digital Terrestrial Television Broadcast Station (DTTBS) in Katsina City, Nigeria. The RSS was measured at intervals along selected routes around the station using a digital signal strength meter. GPS receiver was used to log the line of sight, geographic coordinates and heights of data points from the station. The atmospheric pressure, temperature and humidity corresponding to data points were concurrently measured using a compact weather station whereas the corresponding surface radio refractivity (Ns) values were computed. Data were collected during dry and wet season months’ in the year 2017. Results shown that, Ns is inversely proportional to RSS irrespective of routes and seasons with correlation coefficients of -0.51 and -0.57 during dry and wet season months respectively. Higher mean value of, 358.50 (N-units) was deduced during wet compared to the dry season months of 301.20 (N-units). Average atmospheric pressure of 951.92 and 949.61 (hPa) and as well as humidity values of 32.25 and 77.93 %RH were deduced during dry and wet season months’ respectively. Findings also show that pressure is inversely proportional to RSS. The overall effects of pressure, temperature and humidity on RSS is better understood using the effect of Ns since the latter is derived from those parameters. This study concludes that the specified radio climatic factors have attenuation effect on UHF signal and should be put into consideration when planning link’s design and power budgets on the UHF band.&#x0D;

Reliability Evaluation Method for DVB-T2 Systems on Typical Transmitter Stations

In this paper, we model the Digital Video Broadcasting-Terrestrial 2 (DVB-T2) system on a typical transmitter station in the content regionalization mode by using multilayer graphs to evaluate its reliability parameters. One of the proposed models characterizes the states of the broadcasting system when using only local content insertion in accordance with ETSI TS 102773. The second model, also implemented as a multilayer graph, describes the states of the system when the regionalization devices are cascaded. Based on the proposed expressions for the probability of 100% uptime operation of each broadcasting system, their parameters are evaluated, showing that the system with cascade content insertion has an availability factor that is 3.28% higher than that of the system with content insertion based on physical layer pipe (PLP) replacement, with the direct reservation of the cascade scheme improving its reliability by 9.77%.