High-definition Television Signals Research Articles

Transmission of High-Definition Video Signals and Detection of the Objects Underwater Using Surface Electromagnetic Waves

Transmission of High-Definition Video Signals and Detection of the Objects Underwater Using Surface Electromagnetic Waves

Real-Time Implementation of a Cognitive Radio Node for Video Transmission with Dynamic Channel Selection

This paper endeavors to exploit the extent to which the radio spectrum can be utilized by almagating and enhancing various methods proposed by previous researchers in the field. Cognitive radio research addresses the challenge of spectrum scarcity and underutilization through cognitive radio technology. The realm of cognitive radio research encompasses diverse aspects of its architecture, ranging from spectrum sensing to higher-level strategies. Notably, the navigation strategy employed by cognitive radios constitutes a pivotal layer in these implementations. Thus, this paper focuses on the real-time implementation of a cognitive radio node in a spectrum of licensed users. Leveraging the capabilities of software-defined radios, GNU Radio, GStreamer and Ubuntu OS computers, this investigation introduces a streamlined channel strategy. This strategy uses both short-term and long-term historical data, along with a buffering mechanism, to facilitate the real-time transmission of a high-definition video signal. The successful implementation of this system yields a promising enhancement of approximately 32% in radio resource utilization. Furthermore, the sensing time of the cognitive radio experiences a significant reduction. This research contributes to the advancement of cognitive radio technology and demonstrates the consolidated strategies' practical implications, underscoring their potential to overcome spectrum-related challenges.

Integration of Raspberry Pi and antennas for multiplexing digital signals over a fiber optical communication system

A Fiber Optical Communication System (FOCS) is used to experimentally demonstrate the transmission of multi-channel information of two High Definition (HD) video signals and 18 digital TV channels. These signals are supplied using commercial Raspberry Pi boards and digital TV Antennas, respectively. Both digital signals and lightwaves of a couple of Distributed Feedback (DFB) lasers with wavelengths located at 1547.5 and 1552.5 nm interact with two Mach-Zehnder Intensity Modulators (MZ-IM). The resulting modulated optical signals from each modulator are combined by using an optical coupler. The combined optical field is amplified and transmitted through 30 km of single-mode optical fiber. To demultiplex the combined optical signals, a bandpass optical filter is used, then a PIN-photodetector is connected to recover HD video signals and the 18 digital TV channels. The measured electrical spectrum of the received signals shows that the transmission is performed without interference and the multi-channel information is successfully received in an HD display. The use of wavelengths with linewidths of 10 MHz and an optical fiber with a chromatic dispersion of 17 ps/nm-km allows for a maximum bit rate of approximately 11 Gbps to be achieved numerically. This result guarantees that HD video signals can be experimentally transmitted successfully with Bit Error Rate (BER) values between 10-6 and 10-15 when the optical power of lasers is tuned between 7 and 9 dBm.

48‐Gbit/s 8K video‐transmission using resonant tunnelling diodes in 300‐GHz band

The authors report on a real-time 48-Gbit/s terahertz band wireless communication experiment employing a pair of resonant tunnelling diodes at the receiver and uni-travelling carrier photodiodes at the transmitter. The wireless transmission of uncompressed full-resolution 8K ultra high-definition television video signal is successfully demonstrated in the 300-GHz band for the first time.

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.

Feasibility of Satellite Navigation Using High-Definition Television Tower Transmissions

This paper studies the feasibility of using high-definition television signals for on-orbit satellite navigation. Satellite orbits studied include low, circular orbits of a wide range of altitude and inclination; Molniya orbits, and orbits at the moon. Coverage analyses demonstrate that the high-definition television signals are prevalent: more so if one can receive several types of these signals. High-fidelity signal link budgets demonstrate in this study that high-definition television signals may be received in a variety of orbital environments.

Demonstration of 2.97-Gb/s video signal transmissions in DML-based IM-DDO-OFDM systems

Abstract To further investigate the feasibility of the digital signal processing (DSP) algorithms (e.g., symbol timing synchronization, channel estimation and equalization, and sampling clock frequency offset (SCFO) estimation and compensation) for real-time optical orthogonal frequency-division multiplexing (OFDM) system, 2.97-Gb/s real-time high-definition video signal parallel transmission is experimentally demonstrated in OFDM-based short-reach intensity-modulated direct-detection (IM-DD) systems. The experimental results show that, in the presence of ∼12 ppm SCFO between transmitter and receiver, the adaptively modulated OFDM signal transmission over 20 km standard single-mode fiber with an error bit rate less than 1 × 10−9 can be achieved by using only DSP-based small SCFO estimation and compensation method without utilizing forward error correction technique. To the best of our knowledge, for the first time, we successfully demonstrate that the video signal at a bit rate in excess of 1-Gb/s transmission in a simple real-valued inverse fast Fourier transform and fast Fourier transform based IM-DD optical OFDM system employing a directly modulated laser.

A Q-band radio-over-fiber system for distribution of uncompressed high-definition video signals

A Q-band radio-over-fiber (RoF) system for the distribution of uncompressed high-definition (HD) video signal is proposed and demonstrated. To eliminate the fiber dispersion induced RF power fading, which is a serious problem for the Q-band RoF system, a polarization modulator (PolM) based transmitter is applied, by which the peak of the frequency response of the fiber link can be shifted to any desired frequency. Besides, an injection-locked Q-band optoelectronic oscillator (OEO) is constructed in the receiver to perform the carrier extraction and frequency downconversion. A 40-GHz RoF system is established, which delivers a 720P uncompressed HD video signal to a targeted displayer through a 20-km fiber link and a ∼1-m wireless link.

Novel Hybrid Antenna for Broadcasting Satellite and Terrestrial HD-TV

High-definition television (HD-TV) is available via satellite broadcast and terrestrial HD-TV services. However, antennas that can receive HD-TV signals using different carrier waves (i.e., X band and UHF band) have not yet been designed. Therefore, in an effort to realize such an antenna, we created a slot aperture in the reflector of a typical Broadcasting Satellite (BS) antenna, and investigated its possible use as a UHF-band antenna element. Furthermore, a practical hybrid antenna for BS and terrestrial HD-TV was developed by implementing omnidirectional radiation in a parabolic reflector with a slot. This hybrid antenna exhibited excellent practical performance in a field test.

高清激光显示中的色彩复现系统

On the basis of an 60 inch all solid laser television (TV) prototype, a chrominance signal conversion model from an original TV to a laser TV was established. By researching the characteristics of laser display, the conversion matrix between traditional phosphor TV color system and laser TV color system was derived by using a three color laser (red: 660 nm, green: 532 nm, blue: 457 nm) as primary-color. A gamut conversion circuit between the two color systems was given by utilizing a decode module, a Field Programming Gate Array (FPGA) controlling circuit and a coding module. The roles of these models and their working processing were analyzed, and the gamut conversion to the high-definition video signal was achieved. 11 feature colors displayed with the laser TV and the traditional phosphor TV respectively were measured and compared after conversion and the gamut conversion error is less than 9.8%. The experiment obtains an excellent result of gamut conversion and verifies the color-recurrent ability of high-definition laser TVs.

Wireless communication at 310 GHz using GaAs high-electron-mobility transistors for detection

We report on the first error-free terahertz (THz) wireless communication at 0.310 THz for data rates up to 8.2 Gbps using a 18-GHz-bandwidth GaAs/AlGaAs field-effect transistor as a detector. This result demonstrates that low-cost commercially-available plasma-wave transistors whose cut-off frequency is far below THz frequencies can be employed in THz communication. Wireless communication over 50 cm is presented at 1.4 Gbps using a uni-travelling-carrier photodiode as a source. Transistor integration is detailed, as it is essential to avoid any deleterious signals that would prevent successful communication. We observed an improvement of the bit error rate with increasing input THz power, followed by a degradation at high input power. Such a degradation appears at lower powers if the photodiode bias is smaller. Higher-data-rate communication is demonstrated using a frequency-multiplied source thanksto higher output power. Bit-error-rate measurements at data rates up to 10 Gbps are performed for different input THz powers. As expected, bit error rates degrade as data rate increases. However, degraded communication is observed at some specific data rates. This effect is probably due to deleterious cavity effects and/or impedance mismatches. Using such a system, realtime uncompressed high-definition video signal is successfully and robustly transmitted.

Field Trial of 100-km Reach Symmetric-Rate 10G-EPON System Using Automatic Level Controlled Burst-Mode SOAs

This paper reports the world's first field trial of a 100-km reach symmetric-rate ten gigabit Ethernet passive optical network (10G-EPON) system that uses optical-amplifier-based PON repeaters. Semiconductor optical amplifiers (SOAs) are utilized to handle the 10G-EPON wavelength allocation defined in IEEE802.3av; a fast automatic level control technique is applied to cascaded SOAs for upstream amplification to achieve high gain and wide input dynamic range. An electronic dispersion compensation technique is also applied for downstream detection. These techniques support a 79.5-dB loss budget and 100-km reach transmission with 40 km span lengths. In a field trial, we successfully demonstrate bidirectional real-time uncompressed high-definition television signal transmission over installed standard single-mode fiber links.

An adaptive dynamic range compression with local contrast enhancement algorithm for real-time color image enhancement

Dynamic range compression has become an important function used in modern digital video cameras to improve visual quality of color images suffered from low dynamic range and poor contrast defects. This study addresses real-time implementation of an adaptive dynamic range compression algorithm for color image/video enhancement. To achieve this purpose, we first propose a new image-dependent nonlinear intensity-transfer function to produce a satisfactory dynamic range compression result with less color artifacts. The proposed algorithm is then derived by combining the new adaptive nonlinear intensity-transfer function with an efficient local contrast enhancement algorithm. Moreover, an algorithmic acceleration method is also presented to accelerate the processing speed of the proposed color image enhancement method, achieving real-time performance in processing high-definition video signals. Experimental results validate the performance of the developed method in terms of quantitative evaluation, visual quality, computational efficiency, and power consumption.

Ultrawideband Signal Distribution Over Large-Core POF for In-Home Networks

A proof-of-concept real-time high definition (HD) video stream delivered over 50 m of 1 mm core diameter graded index plastic optical fiber and 3 m wireless link employing multiband orthogonal frequency division multiplexing ultrawideband (UWB) technology is studied and demonstrated. The HD video signal encapsulated into UWB frames exhibited an error vector magnitude performance of 11.9%, which is compliant with Federal Communications Commission requirements. Low-cost and off-the-shelf components were employed to realize a cost-effective solution for broadband in-home networks.

Design and Implementation of the HD Video Signal Converter Based on FPGA

In this paper, based on the FPGA and with a video dedicated A / D converter chip, LVDS coding chip, the design and implementation of a SD(standard-definition) analog video signals to HD(high-definition) digital video signal converter. First, input SD analog video into digital video signals meet the ITU-BT656 standard. Then use the FPGA with the video processing chip and DDR do some corresponding processing to achieve high-definition digital video output. After the actual test, the converter output signal of the image quality is well, meets the design requirements, and to verify the effectiveness of the program.

Deinterlacing with reduced flickering

Deinterlacing has been used to convert interlaced video signals into progressive video signals. Conventional deinterlacing methods with low levels of complexity can lead to deteriorating video quality, particularly in edge areas. Another problematic artifact is flickering, which occurs more frequently as the video size increases. For example, this flickering artifact is more frequently observed in high-definition television signals. In this paper, we propose a flickering artifact reduction algorithm for deinterlacing, which noticeably increases the overall visual quality.

Heterodyne mixing and polarization diversity techniques in radio over fiber system with high sensitivity and dispersion tolerance

We propose and experimentally demonstrate the heterodyne mixing and polarization diversity techniques in radio over fiber (ROF) systems with the advantages of high sensitivity and dispersion endurance. The generation of 2.5 Gb/s optical DPSK and PSK signals, fiber propagation and wireless transmission over 15 GHz subcarrier are illustrated with very low sensitivity of −26 and −32 dBm, respectively. Moreover, based on the wireless polarization diversity techniques, we successfully performed the transmission of 1.3 Gb/s uncompressed high definition television (HDTV) signals with high quality.

Energy-Efficient Multi-Access Technologies for Very-High-Throughput Avionic Millimeter Wave, Wireless Sensor Communication Networks

In this paper, we investigate energy-efficient wireless over fiber access channel and link layer technologies using 60-GHz millimeter-wave (mm-wave) band for avionic very high throughput millimeter-wave sensor communication networks (VHT-MSCNs). An efficient architecture for wireless sensor network employing directional mm-wave wireless access technologies is proposed for systems that require very high throughput, such as high definition video signals, for sensing, processing, transmitting, and actuating functions. Comparisons among various multi-access techniques in terms of power and link layer operation efficiency are presented. A specific multi-access network design for VHT-MSCN is proposed and evaluated here, including energy consumption modeling and protocol frame configuration. A proof-of-concept testbed of the proposed very-high-throughput wireless over fiber sensor communication network using 60-GHz mm-wave radio-over-fiber (RoF) technology in downlink transmission and multi-access technique in uplink transmission has been designed and demonstrated.

High-Speed Flexible Optical Disk for Broadcast Archival Storage

We developed a prototype of a flexible optical disk (FOD) drive with a mechanical stabilizer. We prepared the FOD that had a high recording sensitivity of a recording layer and had low byte error rates below 2 ×10-4 at speeds from 36 to 252 Mbps, and examined the recording of video data on the FOD and the drive. We could record and play a high-definition television (HDTV) video (MPEG-2, 422P@HL) seamlessly at 144 Mbps over the entire area of the FOD and the FOD drive with broadcast video systems. We confirmed that the FOD and the FOD drive can record and play HDTV signals for professional broadcast use.

Enabling ROF Technologies and Integration Architectures for In-Building Optical–Wireless Access Networks

This work presents our recent progress on advanced radio-over-fiber (ROF) technologies for in-building optical-wireless access networks, including multiservice, full-duplex, and polarization diversity ROF system design, as well as the experimental delivery of uncompressed high-definition television (HDTV) signals. The novel polarization diversity technique is proposed to improve receiving sensitivity and increase the anti-interference capacity of the wireless transmission at the in-building environment. Furthermore, the integration architecture of ROF and Ethernet passive optical network (EPON) is investigated, mainly focusing on polar duplex antenna for non-line-of-sight (NLOS) transmission and home gateway for different network topologies. The hybrid system distributes the multimedia services (e.g., HDTV in EPON) and other wireless data services to the terminal rooms over ROF links and thus expands the superbroadband EPON services to the subscribers for the last meters in both wired and wireless ways.