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In the last decade, the transition of digital terrestrial television (DTT) systems from multi-frequency networks (MFNs) to single-frequency networks (SFNs) has become a reality. SFN offers multiple advantages concerning MFN, such as more efficient management of the radioelectric spectrum, homogenizing the network parameters, and a potential SFN gain. However, the transition process can be cumbersome for operators due to the multiple measurement campaigns and required finetuning of the final SFN system to ensure the desired quality of service. To avoid time-consuming field measurements and reduce the costs associated with the SFN implementation, this paper aims to predict the performance of an SFN system from the legacy MFN and position data through machine learning (ML) algorithms. It is proposed a ML concatenated structure based on classification and regression to predict SFN electric-field strength, modulation error ratio, and gain. The model’s training and test process are performed with a dataset from an SFN/MFN trial in Ghent, Belgium. Multiple algorithms have been tuned and compared to extract the data patterns and select the most accurate algorithms. The best performance to predict the SFN electric-field strength is obtained with a coefficient of determination (R2) of 0.93, modulation error ratio of 0.98, and SFN gain of 0.89 starting from MFN parameters and position data. The proposed method allows classifying the data points according to positive or negative SFN gain with an accuracy of 0.97. [ABSTRACT FROM AUTHOR]

This paper intends to formalize a proposal of multiservice schemes based on the Digital Terrestrial Multimedia Broadcast (DTMB) standard, using the TDM (Time Division Multiplexing) and LDM (Layered Division Multiplexing) techniques. It is a well-known fact, that TDM is a widely used technique, which has been implemented in multiple applications; on the other hand, LDM which grew out from the Cloud Transmission concept, is a new promising multiplexing technique for offering simultaneously stationary and mobile/indoor services with different robustness and bitrates using the same radiofrequency channel. Recently, LDM has been accepted as a baseline technology for the new generation digital terrestrial television standards (ATSC 3.0). The proposed LDM implementation that is addressed in this paper is based on a structure of two layers for the services: mobile and fixed. In the same way, three different scenarios of TDM schemes have been defined, with the aim of performing a comparative analysis of the performance of both schemes. Finally, based on the obtained results of the simulations carried out, for each of the multiplexing techniques were identified the optimal operating points. [ABSTRACT FROM AUTHOR]