TV Signals Research Articles

CNN-based image splitting algorithm for dual-layer display

Dual-layer displays (DLDs) can achieve high dynamic range by reducing light leakage via bonding two LC panels. However, the physical distance between the two LC panels introduces a parallax error when the display is viewed off-axis. This paper proposes a convolutional neural network-based image splitting algorithm for improving the display quality of a DLD. In order to improve processing speed, the network structure is designed relatively simply. The training dataset is established mainly based on TV signals. Different from the common image evaluation metrics based on PSNR and SSIM, the paper proposes to apply learned perceptual image patch similarity (LPIPS) to define the loss function for DLDs. The simulation and experiment results show that compared with the existing method, the proposed method has better performance in reducing parallax error and improving image details. The processing time can be shortened by 2.7 times. The proposed CNN-based method can greatly reduce the processing time while maintaining high display quality, which presents high practicability.

RF-DC conversion for RF energy harvesting from digital TV signals using voltage multiplier circuits

RF-DC conversion for RF energy harvesting from digital TV signals using voltage multiplier circuits

Optical wireless communications with InGaN multiple-quantum-well photodiodes grown with the prestrained superlattice interlayer for light detection

InGaN multiple-quantum-well photodiodes (InGaN MQW PDs) grown with an underlying superlattice (SL) are proposed for light detection in optical wireless communications. Experimentally, it was found that the presence of the prestrained SL interlayer with a reduced barrier width can help to relief the biaxial strain of the overlying In0.16Ga0.84N/GaN MQW. This gives rise to a stable emission spectrum and a reduced lifetime of carrier recombination or increased carrier escape from the InGaN wells in proposed InGaN PDs. The improved carrier transport in InGaN MQWs with a reduced polarization field is responsible for the improvement in PD's photoresponsivity provided their In0.16Ga0.84N/GaN MQW was fully depleted under −5 V bias. Further increasing the depletion width by reverse bias, an additional photocurrent from the prestrained SL interlayer leads to the best PD photoresponsivity despite their detectivity also degrading at such a high voltage level (V = −10 V). On the other hand, a 250 Mbit/s directed optical link with a bit error rate of 8.8 × 10−8 is proven to be feasible by using the near-ultraviolet laser diode (LD) and the proposed InGaN PDs (better 3-dB cut-off frequency of 76.1 MHz achieved even under zero bias) as the optical transmitter and the receiver, respectively. Furthermore, the practical application of LD-based optical wireless communications with the SL containing InGaN PDs through real-time transmission of digital TV signals (data rate ∼ 270 Mbit/s) is also demonstrated.

Fast neural network for TV super resolution scaling‐up system

AbstractIn this paper, we propose a modified architecture aimed at reducing the computational demands of the generative adversarial network for super‐resolution image generation. To achieve this, we embedded depth‐wise and point‐wise convolution into the convolution layer, effectively decreasing operational complexity and improving the overall network structure. For training and validation, we utilized a dataset consisting of 900 image pairs with resolutions of 480 × 270 and 1920 × 1080. Our experimental results demonstrated that the proposed method can reduce computational operators by 63% compared to the original network, while still maintaining the quality of super‐resolution images. To enable real‐time implementation, the architecture with light model subsequently deployed it on a GPU processor, allowing for efficient scaling of TV signals for 16× resolution expansion. Our experiments showed that the peak signal‐to‐noise ratio (PSNR) reached approximately 28 dB, and the processing rate ranged from 6 to 14 frames per second. The network effectively produced output with 16 times greater resolution without introducing any blurring and obvious artifact.

Implementation of Spectrum Sensing Algorithm Based on Television White Space Scenarios for Spectrum Aggregation Applications

With the proliferation of mobile devices and diverse mobile applications, wireless operators are experiencing phenomenal growth in the demand for mobile services around the world. These demands have led to the technological responses such as the advancement in radio access, coding and modulation schemes as well as spectrum (carrier) aggregation and cognitive radio capabilities. The aspect of spectrum or carrier aggregation uses cognitive radio technology that implements the dynamic spectrum access for spectrum utilization by sensing and using the underutilized spectrum on co-primary basis without interference to the primary users. In this work, an energy-based, non-parametric TVWS spectrum sensing algorithm was implemented in MATLAB environment. The developed sensing algorithm was aimed at finding free TVWS frequency channel(s) that would be used during spectrum aggregation of channels from TVWS and LTE-A spectrums. The chosen free channel would be configured as the component carrier two (CC2) at the configuration management platform of the TVWS eNode B. The result showed the instantaneous TV channels statuses; free, busy and interfered by computing the PSD expressed in dB while the estimated received power level in dBm for free channels was computed for the UHF range from channel 21 through channel 69. The detectable TV signals’ threshold value was set at -114 dBm. In the ten simulation five cycles carried out, the developed algorithm instantaneously selected channels: 68,34,48,60 and 28 corresponding to the centre (carrier) frequencies of 850MHz, 578MHz, 690MHz, 786MHz and 530MHz, would be dynamically configured as the component carrier two (CC2) in the TVWS eNode Bs during spectrum aggregation process.

Media Manipulation in Young Democracies: Evidence From the 1989 Brazilian Presidential Election

We investigate how dominant media networks can manipulate voters in young democracies. During the first presidential election after the democratic transition in Brazil, TV Globo, the largest and most-watched network in the country, unexpectedly manipulated the news coverage of the last debate 2 days before the decisive second round. In a video segment, Globo unfavorably depicted the left-wing candidate, Luiz Inácio Lula da Silva. Using the geographical distribution of broadcaster-specific TV signals and the timing of election events, we identify the effect of the manipulation net of the effect of the debate itself, showing that Globo’s misleading reporting caused Lula to lose millions of votes. Our results showcase how the media can reshape an election in a single stroke, especially where the media is concentrated and politically inexperienced voters have few other sources of information.

COGNITIVE RADIO SYSTEM FOR DYNAMIC ALLOCATION OF UHF BAND CHANNELS BASED ON 802.11AF AND USING THE ENERGY DETECTION ALGORITHM

This paper describes the development of a cognitive radio system through a software-defined radio approach, using universal software radio peripheral (USRP) devices and digital television equipment for communication in the UHF band. The algorithm was developed in LabVIEW and is based on energy detection, where the average power of the video carrier of the tv signal is calculated and compared with the established threshold value. As a result of detection, free channels are determined and assigned for the transmission of an Secondary User (SU), which will synchronize with the receiver the same working frequency. For the evaluation of the performance tests, a DTT transmitter and receiver were used, which simulate a Primary User (PU), and when the system detects it, it releases the frequency in use of the SU and assigns another free frequency to it to guarantee continuity of trasmission service. Tests were carried out to determine the efficiency of the system, taking into account the response time of the system and its efficiency to allow coexistence of systems within the same spectrum. System response times were measured, being 1.07 s and 41.47 s the shortest and longest response time respectively, for frequency change in order to avoid interference with the PU. Using sampling techniques, the average system response time was 21.33 s, proving that the system is efficient in environments with high interference for services that are not sensitive to latency.

Study the noise effect on the edges and cross correlation of TV images

The noise that associated with TV images is considered to be a very important problem that complicates the developments of these systems. Because of that, it makes the interpretation and analysis of informative images a very difficult process, and lessens their advantages. The most common type of these images are TV images transmitted by antenna work with (VHF, UHF) frequency and Satellite Transmission. Because TV images move through a complicated system in generating the TV or video signal, coding them, transmitting them, and receiving them by decoding and passing with different sets until appearing on screen. This will lead to a loose and fraud for a part of the information sent in the wave. As a result, it will be affected by an additive noise (Gaussian noise) which leads to deforming and destroying the quality of these images.
 This research aimed at studying the effect of the noise influence of this noise on edge as well as study of the relation between the statistical operators that include the mean and standard deviation (µ, σ) of edge’s regions for the components RGB and illumination component L as a function of time and as a function of antenna rotation.
 As well as we studied the relation between (µ, σ) and signal to noise ratio SNR for the cross correlation of edge's regions and for a homogeneous regions as well as for image as a whole once as a function of time and the other as a function of the angle of antenna rotation as in the first.

Dynamic Interference Suppression for TV White Space: the Case of Thailand

In this work, we study the problem of co-existence between the LTE (Long Term Evolution) and the Digital Terrestrial Television Broadcasting (DTTB) channel. There are three scenarios: co-channel, upper and lower adjacent channels. We use the broadcasted signal from channel 3 called ThaiPBS, the actual case of Thailand for our study where the standard of digital terrestrial television broadcasting is DVB-T2 adopting 8 MHz bandwidth, while the 5 MHz bandwidth of LTE is considered as the interference. We propose a dynamic interference suppression method for increasing spectrum usage by optimizing TV white space utilization and minimizing interference. This method adopts the protection ratio concept to suppress the LTE interference on TV receiver. We implement our proposed algorithm as an adaptive interference controller using a Radio Frequency (RF) attenuator and a Raspberry Pi board for our testbed hardware. We illustrate the effectiveness of our proposed algorithm by doing experiment using our testbed and assessing the quality of the received TV signal by adopting the Quality of Experience (QoE) assessment. In our testbed hardware, a Log Periodic antenna is used for receiving the DTTB signal, while an RF digital transmitter is used for generating a 5MHz bandwidth of LTE signal, an ultra-high frequency (UHF) mixer is used to combine both signals, then a field strength meter is used to monitor video picture quality and to analyze the spectrum. According to the experiment, our proposed method can reduce the perceived video distortion by at least 62.5% for co-channel and 87.5% for adjacent channel, while the spectrum usage is increased by 100%.

Methodology to Control IoT Smart Devices Driven by Digital TV Video Scene

This paper presents a novel methodology to control Internet of Things (IoT) devices synchronized with digital TV (DTV) signal dynamic video flow. Through this approach, broadcasters can send commands to digital TV receivers and produce multiples physical effects on IoT devices paired with TV sets. Among IoT devices examples, are: smart lamps, robotic seats, smart watches, wearable devices, etc. Those devices will synchronously react with the video scene, according to the IoT command type received by TV set. With this methodology, broadcasters may multiplex multiple IoT commands and be able to produce several effects at same time, through different IoT devices, creating a home multi-dimensional environment. In case there is any command that does not correspond to any paired device on receiver side, or the command is corrupted, the same is simply discarded. The validation of this methodology is based on the development of a receiver embedded system to detect signalization of IoT commands, Data filtering and IoT device control through Smart TV. The IoT devices control is sync with video scene and is based at time stamps added to the DTV signal. Furthermore, to check transceiver channel behavior, a transport stream benchmark, composed by IoT commands data flow multiplexed with audio and video medias in multiple complexity levels, was generated. Lab experiments with transmission tests and IoT devices control results shown technical feasibility to use this methodology in a real digital TV environment.

Radiofrequency Exposure Levels in Greece.

Medical Physics Department (Medical School, University of Thessaly) participated in a Greek National EMF research program (EDBM34) with the scope to measure and evaluate radiofrequency (RF) exposure (27-3000 MHz) in areas of sensitive land use. A thousand (1000) measurements were carried out at two "metropolitan locations" (Athens and Thessaloniki: 624 points) and several rest urban/rural locations (376 points). SRM 3006 spectrum analyzer manufactured by Narda Safety Test Solutions was used. The broadband mean electric field in metropolitan areas was 0.41 V/m, while in the rest of Greece was 0.36 V/m. In metropolitan areas, the predominant RF source was the TV and Radio FM signals (36.2% mean contribution to the total RF exposure level). In the rest areas, the predominant source was the systems of the meteorological and military/defensive service (31.1%). The mobile sector contributed 14.9% in metropolitan areas versus 12.2% in the rest of Greece. The predominant mobile source was 900 MHz in both cases (4.5% in metropolitan areas vs. 3.3% in the rest of Greece). The total exposure from all RF sources complied with the International Commission on Non-Ionizing Radiation Protection (ICNIRP) 2020 safety guidelines [ICNIRP, 2020]. The maximum exposure level was 0.129% of the limit for the metropolitan areas vs. 0.110% for the rest of Greece. Nonremarkable differences between metropolitan areas' exposure and the rest of Greece. In most cases, new 5 G antennas will be added to the existing base stations. Thus, the total exposure may be increased, leading to higher safety distances. © 2023 Bioelectromagnetics Society.

Application of Network Technologies in Low-Budget Television Production

The article considers the classical scheme of the broadcast news studio and the principle of operation of the television broadcasting system on the example of the standard of the international digital television system, which is the reference model of terrestrial digital television transmission. The structural scheme of the broadcast news studio is given, the functions of each block of the studio and the principle of their work are described. The diagram of the digital television system shows how the signal from the studio passes through the stages of encoding and modulation to the broadcasting antenna, and then the demodulated and decoded TV signal appears in the digital television application on the viewer's side. The interactive communication channel is also discussed in more detail. The diagram of the interactive communication channel presented in this article shows how the communication between the broadcasting company and the viewer of digital television takes place. However, given the current tendency of TV channels to move from broadcasting on digital television to online broadcasting on streaming platforms, the article considers an example of organizing an online broadcast on the YouTube platform. Using the example of equipment from the classical scheme of the broadcast studio, the selection of similar low-budget equipment for organizing a studio for online broadcasts was carried out. The list of low-budget equipment includes a video mixer, video cameras, lighting equipment and two types of microphones. The advantages and disadvantages of low-budget equipment are indicated, from which it can be concluded that low-budget equipment is not of poor quality, but is designed for a smaller number of connected equipment, so it is suitable for use in small television studios. The functions and possibilities of using the selected Blackmagic ATEM Mini Pro video mixer are considered. A scheme for organizing a live broadcast on the YouTube streaming platform using the selected equipment is presented. The low budget of the studio is substantiated by estimates and comparison with the budget of a similar educational television studio. The possibilities of remote access organizing to the workplace via VPN (Virtual Private Network) and RDC (Remote Desktop Connection) are also considered. These features allow employees to work from a remote location, not directly in the studio. The purpose of the article was to determine how does remote access delay the work of the studio and complicate the process of launching online broadcasts. Measurements of connection delay and broadcasting were carried out. According to the results of the measurements, it was concluded that both VPN and RDC insignificantly affects the connection speed of the equipment, so remote work can be equally comfortable as working directly in the studio. The difference between remote work and direct work in the studio consists of in the preliminary configuration of devices for remote connection and also remote work depends on the Internet connection entirely and light availability in the studio.

Enhanced 5G Mobile Broadcasting Service With Shape-Adaptive RIS

There emerges a strong trend recently to create an intelligent and controllable wireless transmission environment by installing reconfigurable intelligent surfaces (RIS) on the surface of diverse. We research the use of RIS in 5G multicast TV applications in this paper. In particular, the shape-adaptive RIS is developed to relay 5G multicast TV signals and achieve extra RIS gain. To optimize the shape bending in RIS model, we employ the algorithm of Deep Deterministic Policy Gradient (DDPG), a reinforcement learning technique that combines both Q-learning and Policy gradients. Our simulation results show that RIS can considerably enhance the SINR of worst users and improve the system’s overall Modulation and Coding Scheme (MCS) level for 5G mobile broadcasting services.

Statistical analysis of atmospheric parameters, noise temperature and digital terrestrial television signal strength over Jos metropolis, Plateau state, Nigeria

The study of the relationship between the Received Signal Strengths (RSS) from Unity TV (786 MHz) located at Rayfield (9.84 o North 8.89 o East), Jos, Plateau State and some atmospheric parameters with noise temperature has been done using two years half-hourly data. The measurement was carried from 5 am and 9 pm daily. The analysis was carried out using the regression, co-integration and Granger causality models. The results show that the RSS is higher in the morning hours (5.00 am–9.00 am) late in the evening (6.30 pm–9.00 pm) but lower between 9.00 am and 6.30 pm. This might be due to the “dusty” atmosphere and low reflection of ionosphere in the day time which causes signal attenuation within the day time. The correlation coefficients from the coefficient of determination (R squared) of 0.88, 0.004, 0.838. 0.25, 0.867, and 0.112, are −0.94, −0.07, 0.92, −0.50, −0.93, −0.334 for atmospheric temperature, pressure, relative humidity, wind speed, noise temperature and rainfall respectively. It means all the independent variables except relative humidity are inversely proportional with the RSS. Also, the higher R2 values for atmospheric temperature, relative humidity and noise temperature respectively, indicates higher correlation between RSS and these parameters. It can be inferred that the models are suitable for predicting Unity TV (UTV) signal strength and that of other TV stations in Jos and environs, using T, RH and NT as inputs. The results also showed that there is a co-integration and Granger Causal relationship between the parameters and RSS.The result will find applications to the Nigeria Broadcasting Commission in the assigning of frequencies taking atmospheric parameters into considerations, Radio Engineers and Scientists, Satellite link designers, and mobile communication experts for the link budget design and appropriate equipment deployment based on the atmospheric condition on the geographical areas.

Positioning in Urban Scenarios Based on Smartphone Camera/IMU and Digital TV Signal

The built-in sensors of smartphone, such as cameras, accelerometers and gyroscopes, provide abundant environmental information for positioning. VIO (visual-inertial odometry) can be derived from the embedded camera and inertial sensors to provide the estimation of a continuous and smooth trajectory of the pedestrian. However, the trajectory will drift due to the accumulation of system errors. Currently, DTV (digital TV) signal has been verified to be promising for precise ranging in urban scenarios. Therefore, this paper investigates a method of fusing the VIO with the ranging information from DTV signal to improve the positioning accuracy. An Extended Kalman filter is presented to estimate pedestrian mobile state. Field tests have been carried out and the fusion results can effectively reduce trajectory drift errors and improves positioning performance.

The negative effects of the corona effect on the propagation of radio and TV waves

Due to the ever-increasing demands placed on the quality of reception of radio and TV waves, and that these demands are manifested by a considerable number of complaints against obstacles, especially in those countries that have a highly developed radio-television network, the factors that can reduce the efficiency of reception of transmissions, for example: radio broadcasting and the efficiency of many other services, attract more and more attention. High-voltage power lines cause significant high-frequency radio-television obstacles, therefore, the current and future high-voltage lines that are planned to be built will require better choices to be taken into account during design (alternative) in such a way that the problem of obstacles is reduced. Weather deterioration (rain, humidity) significantly increases the electrical discharges and in this case the interference field also increases, which negatively affects the propagation of radio and TV waves. The corona effect as a phenomenon intensifies especially in cases of bad meteorological conditions, in this case, in addition to the noise in the vicinity of the airline where the corona effect occurs, the smell of ozone can also be felt, then the electromagnetic waves that prevent the reception of radio and TV signals appear. As you can see, the corona has harmful consequences, so it is undesirable in the work of air lines, especially in high voltage ones. The purpose of this scientific research is to analyze the negative effects of the corona effect on the propagation of radio and TV waves and the possibility of limiting or reducing these negative effects.

Ambient Backscatter Communications in Mobile Networks: Crowd-Detectable Zero-Energy-Devices

In this paper, we introduce the new concept of Crowd-Detectable Zero-Energy-Devices. Such devices harvest solar or ambient light energy to power themselves, backscatter ambient waves to communicate, and are detected simultaneously by a smartphone connected to the network, and by the network itself, as long as the device is close to the considered smartphone. Such a device is a promising sustainable solution for the future of the Internet of Things. We describe an example of use case: asset tracking with zero added energy, zero new signals and zero new infrastructure in the network, thanks to the anonymous and transparent participation of smartphones connected to the wireless network. We then present our first prototypes of such devices that backscatter TV, 4G and 5G signals, and show our first experiments in challenging conditions and environments.

Preliminary performance evaluation and verification of digital terrestrial television signal propagation

This article presents the computer simulation and field test measurement results on Channel 29 for the preliminary performance evaluation and verification of the newly-installed Lesotho digital terrestrial television network based on DVB-T2 standard following the guidelines and techniques specified by the ITU-R BT.2035-2. It evaluates, at predetermined outdoor locations for fixed and mobile reception, parameters such as received signal strength, signal quality, bit-error rate (BER) and threshold-of-visibility (ToV) together with TV signal decoding (observation of screen artefacts) for quasi error-free reception. The results indicate that at over 97% of the test sites/points at the university town of Roma, the main Berea Plateau transmitter from the capital city (Maseru) broadcasts digital television service with enough signal level and quality to be properly decoded. The measured signal strength threshold ranges above -50 dBm for good reception, -64 dBm to -50 dBm for acceptable reception and -69 dBm to -64 dBm for poor reception. With the noise floor at about -73 dBm, the minimum required C/N of around 23 dB for good reception and about 4 dB for ToV have been recorded. The relative values of minimum required respective signal strength and signal quality for ToV obtained from the set-top box are 33% and 18% for stationary reception, while they give 37% and 20% for mobile reception.

CHAOTIC COMPRESSIVE SENSING OF TV –UHF BAND IN IRAQ USING CHEBYSHEV GRAM SCHMIDT SENSING MATRIX

Cognitive radio (CR) is a promising technology for solving spectrum sacristy problem. Spectrum sensing is the main step of CR. Sensing the wideband spectrum produces more challenges. Compressive sensing (CS) is a technology used as spectrum sening in CR to solve these challenges. CS consists of three stages: sparse representation, encoding and decoding. In encoding stage sensing matrix are required, and it plays an important role for performance of CS. The design of efficient sensing matrix requires achieving low mutual coherence . In decoding stage the recovery algorithm is applied to reconstruct a sparse signal. İn this paper a new chaotic matrix is proposed based on Chebyshev map and modified gram Schmidt (MGS). The CS based proposed matrix is applied for sensing real TV signal as a PU. The proposed system is tested under two types of recovery algorithms. The performance of CS based proposed matrix is measured using recovery error (Re), mean square error (MSE), and probability of detection (Pd) and evaluated by comparing it with Gaussian, Bernoulli and chaotic matrix in the literature. The simulation results show that the proposed system has low Re and high Pd under low SNR values and has low MSE with high compression.

Hardware Update through Digital TV Signals

This paper presents a new hardware reconfiguration approach named hardware reconfiguration through digital television (HARD), which can update FPGA hardware modules based on digital TV (DTV) signals. Such a scheme allows several synthesized hardware cores (bitstreams) signaled and broadcast through open DTV signals via data streaming to be identified, acquired, decoded, and then used for system updates. Reconfiguration data are partitioned, encapsulated into private sections, and then sent in a carrousel fashion in order to be recovered by modified receivers. Service information content, specially designed for identifying and describing the characteristics of multiplexed hardware bitstreams, was added to the transmitted signal and provided all necessary information in the traditional DTV style. The receiver framework, in turn, checked whether those characteristics corresponded to its embedded reconfigurable devices and, if a match was found, it reassembled the related bitstreams and reconfigured the respective internal circuits. Experiments performed with an implementation of the proposed methodology confirmed its feasibility and showed that remounting and reconfiguration times were satisfactory and presented no blocking aspect. Finally, HARD can be used in several designs regarding intelligent reconfigurable devices, minimize device costs in the long term, and provide better hardware reuse.