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ABSTRACT: This paper presents an analysis of the characteristics of the DVB-T2 standard to deliver 3DTV contents (3DTV). The work has been based on the current state-of-the-art developments in technologies that enable 3DTV delivery, from production to displays, with special emphasis on formats and coding efficiencies. Based on bitrate and format requirements the capacity of DVB-T2 is investigated, proposing two roll-out scenarios and discussing the associated DVB-T2 configuration parameters. The target receivers are both fixed and portable, and different backward compatibility problems and solutions are highlighted. The result of this work is an estimation of the number and type of services (both 2D and 3D) that this standard will be able to deliver in the mid term future as 2D HD and 3D services become commercially available.
IEEE Transactions on Broadcasting 07/2011; · 1.70 Impact Factor
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ABSTRACT: The 26 MHz band is currently allocated for international broadcasting by means of the ionospheric propagation. However, sky waves are strongly dependent on the ionosphere conditions and signal reception is not always possible. As a consequence, this HF frequency range is scarcely utilized and an optimization of its use is required. The DRM (Digital Radio Mondiale) standard provides enough robustness to enable reliable audio reception taking advantage of the ground wave propagation at these frequencies. According to this, local coverage is viable in this part of the spectrum, as proved the field trials and studies carried out in the last years. Nevertheless, it is still necessary to establish the general guidelines for the set up and consolidation of the corresponding digital networks. Thus, the planning factors and procedures for digital local broadcasting services in the 26 MHz band are defined in this paper, along with reference parameter values and recommended system configurations for this new application.
IEEE Transactions on Broadcasting 04/2011; · 1.70 Impact Factor
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ABSTRACT: This letter presents a study of indoor radio noise levels in the Medium Wave band up to 2 MHz, based on field trials. The work is based on long-term measurements carried out in buildings located in the areas of Bilbao and Vitoria in the north of Spain. The studied channels are centered in 630, 675, 1035, 1242, 1359, 1620, 1720, and 1910 kHz. The noise variation between daytime and nighttime and the variation depending on the type of building, office or household, have been analyzed. The obtained values, compared to the values predicted in ITU-R P-372 for outdoor locations in city environments, are higher. Reference values for radio planning are given for these frequency bands.
IEEE Antennas and Wireless Propagation Letters 02/2011; · 1.37 Impact Factor
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ABSTRACT: Updated reference indoor radio noise values in the medium wave band are provided. The results are based on an extensive trial: 339 locations in buildings located in two cities in the north of Spain gathering data at frequencies of 630, 675, 1035, 1242, and 1620 kHz. The increase in absolute noise levels as well as location variability values has been found significant if they are compared to values reported in ITU-R P.372 and other recently published values for measurements outdoors. These results are essential for planning upcoming digital broadcasting services (In Band On Channel HD-RADIO and Digital Radio Mondiale) to receivers located indoors. Provided is a prediction formula as a function of the frequency obtained from measurements by multiple regressions, differentiating households from office buildings, where noise levels have been found noticeably higher.
Electronics Letters 09/2010; · 0.96 Impact Factor
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ABSTRACT: In this paper, we propose a novel method to validate channel estimations based on two different analysis that compare the similarity between the real signal measurements and the values obtained after processing the theoretical transmitted signal through the estimated channel. The merit of this technique is its simplicity, its flexibility and the possibility to identificate with one parameter the quality of our estimation. The performance is evaluated over a real Gaussian channel, and the method shows its efficiency for this type of channels.
Antennas and Propagation (EuCAP), 2010 Proceedings of the Fourth European Conference on; 05/2010
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ABSTRACT: This paper presents an analysis of the ground wave propagation in the 26 MHz band based on a comparison between measured and predicted field strength values. To do this, a set of empirical data obtained from a measurement campaign of a DRM experimental local service was used. Simulated field strength values were calculated applying two different models that account for the space and surface wave propagation respectively. The corresponding prediction errors were analyzed and a correction factor due to the terrain irregularity was obtained in order to increase the accuracy of the results.
Antennas and Propagation (EuCAP), 2010 Proceedings of the Fourth European Conference on; 05/2010
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ABSTRACT: This paper presents the first field trials carried out in Spain to test HDTV reception using DVB-T and DVB-T2 systems. High definition and standard definition digital television contents and services were multiplexed and broadcasted from a terrestrial transmitter. The aim of these trials was to analyze DVB-T2 technology when this system is configured according to the needs of terrestrial HDTV broadcasting and to compare the results with DVB-T technology in terms of CNR requirements and achieved data rate. Field measurements were carried out in different scenarios and reception conditions. The study presented in this paper is focused on fixed reception, Gaussian channel, because it is the expected reception condition for HDTV.
Broadband Multimedia Systems and Broadcasting (BMSB), 2010 IEEE International Symposium on; 04/2010
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ABSTRACT: This paper presents DVB-T2 laboratory tests carried out for testing mobile reception. The aim of this study is to analyze DVB-T2 technology in order to obtain system assessment on pedestrian and low speed mobile reception. Results provide first approximation about the influence of the new options included in the standard. Furthermore, they can provide noteworthy information for next field trials planned to validate the best parameter set for handheld reception.
Broadband Multimedia Systems and Broadcasting (BMSB), 2010 IEEE International Symposium on; 04/2010
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ABSTRACT: This paper presents a study of radio noise levels in the Medium Wave band based on field tests. The planning of the measurement campaign, discussion about the methodology, the process of registered data and results are explained.
Electromagnetics in Advanced Applications, 2009. ICEAA '09. International Conference on; 10/2009
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ABSTRACT: In this work, the usefulness and limitations of a planning tool that combines a propagation prediction method and a modern heuristic technique when applied to improve the coverage area in single frequency networks (SFN) is presented. The propagation prediction method uses 3D digital terrain maps along with a propagation model to estimate the contribution of any transmitter of the SFN at each location within the region in which the SFN is intended to be deployed, given in terms of parameters such as the received power and propagation delay. Furthermore, a particle swarm optimization (PSO) algorithm is used to optimize the transmission parameters of any of the transmitters within the SFN, including transmitters delay or gain for their sector antennas, in order to exploit the multipath tolerance in OFDM receivers. Preliminary results comparing the performance of different PSO schemes considering as the canonical problem a SFN consisting of eighteen transmitters, in which transmitters and receivers have been simplified, are reported and discussed. Moreover, results considering sector and directive antennas at the transmitter and receiver sides, respectively, are also included.
Broadband Multimedia Systems and Broadcasting, 2009. BMSB '09. IEEE International Symposium on; 06/2009
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ABSTRACT: This paper presents a statistical characterization of the skywave interference conditions for DRM (Digital Radio Mondiale) local services in the 26 MHz band. This work is the first step to analyze the feasibility of a world frequency planning for local services in this band and is focused on regular ionospheric propagation. The analysis has been based on two parameters: Maximum Usable Frequency (MUF) and field strength received level. Values of these parameters were obtained by means of two prediction tools, both of them referenced by the ITU and developed by the NTIA/ITS: REC533 and VOACAP. Simulations were carried out defining combinations of a wide range of Sun Spot Number (SSN) values characterizing a complete solar cycle, 12 months per year and 24 hours per day. This first study has focused on Europe and was done for 20790 circuits after establishing 5 representative transmitters and taking this continent as the reception area. From the resultant database, cumulative distribution functions, as well as other significant statistics, were computed and analyzed for both parameters. The obtained results show the ionospheric conditions that give raise to interfering signals between DRM local services and establish when their propagation is critical.
Ionospheric radio Systems and Techniques, 2009. (IRST 2009). The Institution of Engineering and Technology 11th International Conference on; 05/2009
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ABSTRACT: Single frequency networks (SFN) are usually considered to deploy OFDM modulation based digital broadcast systems, exploiting the multipath tolerance of the OFDM receivers, which are capable of combining signals coming from several transmitters with different propagation delays. In this work, a planning tool is proposed to improve the coverage area in SFN networks, optimizing transmission parameters such as the transmitters delay or power, using 3D digital terrain maps along with a propagation prediction tool to estimate the power received at each location inside the coverage area. A heuristic particle swarm optimization algorithm is used (PSO) to optimize transmission parameters. The approach proposed makes it possible to consider several configurations regarding both transmitters and receivers. Preliminary test results are shown for a SFN with eighteen transmitters and omnidirectional radiators at both sides that demonstrate the usefulness of the approach. Furthermore, results considering receivers with directive antennas as well as transmitters with sectored antennas are also included and discussed.
Vehicular Technology Conference, 2009. VTC Spring 2009. IEEE 69th; 05/2009
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ABSTRACT: This paper analyses the performance of a DTT (digital terrestrial television) broadcasting system that includes MIMO-OFDM techniques. The benefits of these techniques are studied comparing the results for different MIMO 2 x 2 (multiple input multiple output), MISO 2 x 1 (multiple input single output) and SISO (single input single output) system configurations. Different propagation channel models and configurations are considered for each diversity scheme. This study has been carried out in the context of development of the next generation DVB-T, called DVB-T2.
Vehicular Technology Conference, 2009. VTC Spring 2009. IEEE 69th; 05/2009
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ABSTRACT: This paper presents the results obtained from three extensive field trials of medium wave DRM (digital radio mondiale) which were carried out in Madrid (Spain), Delhi (India) and Mexico D.F. (Mexico) using different transmission frequencies. The aim of the paper is to provide the first approach to medium wave field strength spatial variability empirical parameters in urban environments. A methodology to study the empirical spatial variability is defined and finally the paper includes attenuation values according to urban features such as width of streets and height of buildings and provides statistics for different occasional field strength fading occurrences in urban environments.
Antennas and Propagation, 2009. EuCAP 2009. 3rd European Conference on; 04/2009
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ABSTRACT: A study of DVB-T (Digital Video Broadcasting-Terrestrial) signal variability for indoor reception environments is stated in this paper. A commercial signal was measured and analyzed in order to obtain C/N threshold values that account time and space fluctuations. In this way, results increase the accuracy of the values provided by the ETSI (European Telecommunications Standards Institute) standard and other studies that assume static propagation channels. On the other hand, the fading influence due to people walking near the reception antenna has been proved as critical for correct reception. Characterization of this effect has been made in terms of its depth and duration. The results obtained results improve DVB-T network planning and could be also relevant for other technologies sharing similar frequencies and bandwidths.
IEEE Transactions on Broadcasting 04/2009; · 1.70 Impact Factor
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ABSTRACT: Recently developed digital radio systems for the medium wave band require accurate field strength prediction algorithms for coverage estimation. Presented is a comparison of estimation accuracy provided by the most relevant field strength prediction methods employed for ground-wave propagation at this band. Moreover, a field strength prediction method recently developed by the authors, has been considered in the analysis. Empirical values from measurement campaigns carried out in three different broadcasting networks have been used to analyse the accuracy of the prediction methods. Comparison between predicted and measured values allows objective evaluation of the estimation accuracy of each method under different reception conditions. The proposed method provides the most accurate results on field strength predictions, consequently it is a suitable method for the coverage estimation of the new digital radio systems.
Electronics Letters 11/2008; · 0.96 Impact Factor
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ABSTRACT: Some basic rules and values to include the attenuation effect of terrain obstacles in the medium wave (MW) band are presented. The analysis applies to ground wave propagated signals and focuses on the new digital broadcasting systems (HD-RADIO/IBOC and DRM) that require accurate predictions for appropriate network planning. This study is based on field strength data from a measurement campaign and the results represent a complementary approach to numerical solutions for planning purposes. A simple but efficient classification of the terrain prominences is presented and attenuation curves are calculated.
IEEE Transactions on Antennas and Propagation 09/2008; · 2.15 Impact Factor
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ABSTRACT: Wind turbines can cause degradation to the existing transmission systems, especially in the analogue television terrestrial broadcasting and radar services. The main effects of the interference are caused by the reflected signals in the support tower and in the rotating blades of the wind turbines. Empirical trials are necessary in order to adequately characterize the influence on the quality of the transmitted services, and to determine the parameters involved. The existing techniques to evaluate this influence are cost prohibitive or do not offer the required accuracy. In this paper, a low cost technique for evaluating the reflected signals from wind turbines is proposed, based on the analysis of the channel impulse response of the digital terrestrial television services. The results show that this technique provides accurate and reliable results.
Instrumentation and Measurement Technology Conference Proceedings, 2008. IMTC 2008. IEEE; 06/2008
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ABSTRACT: This paper presents measurement-system design and measurement techniques developed to study digital-radio-mondiale signal behavior and system performance. The solution proposed considers different reception conditions and environments. Some aspects, like antenna selection and both internal and external noise measurements, have turned out to be key factors and are also presented.
IEEE Transactions on Instrumentation and Measurement 04/2008; · 1.21 Impact Factor
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ABSTRACT: This paper presents an up to date study on external noise levels in the medium wave band based on field trials carried out in Spain and Mexico during years 2004 and 2005 respectively. External noise levels predicted by the ITU-R P.372 recommendation are based on measurements carried out more than 30 years ago and no updated results for the medium wave band have been published in this time. An increment on these noise levels have been measured, which leads to a significant impact on the minimum usable field strength requirements for the broadcasting systems used in this frequency band, such as the new Digital Radio Mondiale (DRM) and In-Band/On-Channel (IBOC) systems
IEEE Transactions on Broadcasting 07/2007; · 1.70 Impact Factor
