Radio frequency interference to DVB-T reception from LTE systems in adjacent bands

Australians have recently benefited from the switch-over to digital television which has freed many channels called digital dividend. Australia's digital dividend is the frequency range of 694 MHz to 820 MHz which is used to operate Long Term Evolu- tion (LTE) technology. In Australia there were 57 VHF and UHF channels used for television broadcasting. After the completion of switch-over process, UHF channels 52 to 69 were freed up which is considered as Australian digital dividend. When LTE Frequency Division Duplex (FDD) system and digital television services operate in adjacent UHF bands, LTE FDD transmitters can cause harmful interference to digital video broadcasting-terrestrial (DVB-T). So in this study, we have presented the compatibility of operating LTE FDD services in the digital dividend spectrum identified in Australia. We have used interference analysis method to calculate the minimum separation distance between LTE FDD and DVB-T sys- tem and Monte Carlo Simulation for calculating the probability of location within considered DVB-T area that suffer maximum level of interference. Also, there are some unused channels where digital television operates called TV White Spaces (TVWS). TVWS can be utilized to operate the secondary devices such as LTE Time Division Duplex (TDD) which helps to address spectrum scarcity issue. We have presented the study of the interference on DVB-T when LTE TDD are operating on TVWS. We have used interference analysis method to calculate mini- mum separation distance between LTE TDD and DVB-T. The results of our study show that increasing the guard band reduces the interference to adjacent channel

Investigation of Techniques for Reducing Mobile Communication Systems Harmful Out-Of-Band Emission

Electromagnetic compatibility in the newly designated Long-Term Evolution (LTE) mobile network in the 790–862 MHz frequency band from perspective of interference management between neighbouring services are analysed in the dissertation. Main focal point of this dissertation is on the problems that face LTE networks based on Orthogonal Frequency-Division Multiplexing (OFDM) due to the relatively strong side lobes around the active subcarriers in the main communication channel, which introduces interference effects between LTE stations and other services. The introductory chapter presents the investigated problem, objects of research, importance of the dissertation, describes research methodology, scientific novelty and the defended statements. The situation in the 790–862 MHz frequency band is overviewed regarding most sensitive challenges in the first chapter: LTE stations’ influence on Short-Range Devices (SRD), digital terrestrial TV broadcasting (DVB-T) and aeronautical radio navigation systems (ARNS). The noticeable lack of information is observed regarding SRD and LTE electromagnetic compatibility. The Filter Bank Multicarrier Transmission technique (FBMC) is pro-posed as means to minimize adjacent band interference in the 790–862 MHz frequency band. Main FBMC benefits are presented through comparison with reference case of OFDM. The key advantage of FBMC technique is derived from its low out-of-band leakage, which guarantees minimum harmful interference level between stations using adjacent channels. The harmful interference of LTE mobile stations’ influence on Short-Range Devices operating in the 863–870 MHz frequency band is analysed in the second chapter. Two analysis methods are used in this study: first applying theoretical analysis using Minimum Coupling Loss calculations, then statistical Monte-Carlo in order to verify results obtained in theoretical approach. The third chapter is focused on the experimental analysis to reproduce the situation that was investigated in theoretical analysis chapter. Verification of theoretical analysis by practical measurements confirmed that the LTE user equipment (UE) emissions may affect SRD devices and completely or partially disrupt their communications at distances of up to several meters from LTE UE. The obtained results are summarized and general conclusions are drawn

Analysis of coexistence and mutual interference between mobile and digital television systems

La creciente demanda de servicios de comunicaciones inalámbricas multimedia es un factor clave en los mercados más desarrollados. Así, las palabras de moda en las comunicaciones personales “acceso para cualquier persona, en cualquier sitio, en cualquier momento y para el servicio deseado”, implican una demanda notoria y creciente del Espectro Radioeléctrico. En este sentido, la última Conferencia Mundial de Radiocomunicaciones 2007 (CMR-07) atribuyó la parte alta de la banda UHF a las redes móviles como servicio co-primario a partir del 2015 en la Región 1, aprovechando el Dividendo Digital debido a la mayor eficiencia espectral de la TV digital con respecto a la analógica. Esto tiene el potencial de causar una interferencia perjudicial entre los sistemas de televisión y los sistemas móviles y necesita ser analizado con atención. En este artículo presentamos un estudio del problema de la interferencia co-canal en dicho escenario, proponiendo una metodología para tener en cuenta la interferencia entre una red móvil LTE y un sistema televisivo DVB-T, poniendo de relieve el comportamiento diferente de los dos radioenlaces.The ever increasing demand for multimedia wireless communication systems is a key feature of more advanced markets. The buzzwords of personal communications, meant to provide “access to anyone, anywhere, at anytime to the wanted service”, implies that radio spectrum demands are dramatically increasing in most developed markets. The last World Radiocommunication Conference (WRC-07) allocated on a co-primary basis the upper part of the UHF band to mobile services as from 2015 in Region 1, taking advantage of the Digital Dividend due to the higher spectrum efficiency of digital TV with respect to the analogue system. This will cause potentially harmful mutual interference between TV and mobile radio services, that needs to be carefully analysed. In this paper we present a study of the co-channel interference problem, proposing a methodology to take into account the mutual interference between a LTE mobile network and a DVB-T system and highlighting the different behaviour of the two radio links

Analisis Interferensi T-DAB Dan TV Analog Pada Pita Very High Frequency (VHF)

Kehadiran teknologi digital telah membawa Perubahan di dalam berbagai aspek kehidupan, tak terkecuali di dunia penyiaran. Digitalisasi dibidang penyiaran diyakini dapat memberikan manfaat dalam hal efisiensi spektrum frekuensi radio. Berkaitan dengan penyiaran radio, Menteri Komunikasi dan Informatika telah menetapkan DAB family sebagai standard penyiaran radio digital di Indonesia. Kajian dilakukan untuk mendapatkan jarak minimum yang diperlukan antara sistem T-DAB dan TV analog sebagai solusi terhadap kemungkinan interferensi. Analisis dilakukan dengan bantuan SEAMCAT. Berdasarkan hasil analisis disimpulkan bahwa kanal A T-DAB merupakan kanal yang paling rentan terhadap interferensi; Untuk mencapai probabilitas interferensi maksimum 5%, separasi geograpis minimum antara cakupan terluar TV analog kanal n dan transmitter terluar pada jaringan SFN T-DAB untuk kanal (n- 1)D, nA, nB, nC berturut-turut adalah 220 Km, 290 Km, 145 Km dan 40 Km. Sedangkan untuk kanal nD dan (n+1)A dapat dioperasikan tanpa separasi geograpis dengan TV analog

Coexistence of digital terrestrial television and next generation cellular networks in the 700 MHz band

"(c) 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works."With the spectrum liberation obtained by the deployment of digital terrestrial television and the analog TV switch-off, new bands are being assigned to IMT LTE. In the first cellular deployments in the digital dividend at the 800 MHz band, problems emerged due to the interference cellular networks can cause to DTT signals. Possible solutions imply either an inefficient use of the spectrum (increasing the guard band and reducing the number of DTT channels) or a high cost (using anti-LTE filters for DTT receivers). The new spectrum allocated to mobile communications is the 700 MHz band, also known as the second digital dividend. In this new IMT band, the LTE uplink is placed in the lower part of the band. Hence, the ITU-R invited several studies to be performed and reported the results to WRC-15. In this article, we analyze the coexistence problem in the 700 MHz band and evaluate the interference of LTE signals to DTT services. Several coexistence scenarios have been considered, and laboratory tests have been performed to measure interference protection ratios.Fuentes, M.; García Pardo, C.; Garro Crevillen, E.; Gómez Barquero, D.; Cardona Marcet, N. (2014). Coexistence of digital terrestrial television and next generation cellular networks in the 700 MHz band. IEEE Wireless Communications. 21(6):63-69. doi:10.1109/MWC.2014.7000973S636921

Utjecaj LTE sustava zasnovanog na kognitivnoj radio tehnologiji na DVB-T2 sustav zasnovan na metodi diverzifikacije

In recent years, the development of advanced wireless communication systems has been rapidly progressing. In Europe, the 2nd Generation Terrestrial Digital Video Broadcasting (DVB-T2) and Long-Term Evolution (LTE) are the most promising techniques to provide multimedia services efficiently (in flexible quality and with high spectrum efficiency). The purpose of this work is to explore possible influences of the LTE {uplink services}, using cognitive radio (CR) technology, on the area which is covered by DVB-T2 services. In the case of DVB-T2, both single-input single-output (SISO) and multiple-input single-output (MISO) transmission techniques are considered. The defined coexistence scenarios are measured with an appropriate measurement testbed. The performance of the received TV signal is evaluated on its physical layer (PHY) level. The obtained results allow better understand the influence of LTE system on DVB-T2 which is using diversity technique in the same RF channel (co-channel coexistence). One of the main results is that there are the same requirements on the Forward Error Correction (FEC) decoding process in the DVB-T2 receiver, when power imbalances between TV transmitters (an both SISO and MISO modes) are considered at the interfering LTE signal. This finding was also proved by analysis of variance (ANOVA).U posljednje vrijeme se znatno ubrzao razvoj naprednih bežičnih komunikacijskih sustava. U Europi metode prijenosa signala zasnovane na DVB-T2 (eng. 2nd Generation Terrestrial Digital Video Broadcasting) i LTE (eng. Long-Term Evolution) metodama najviše obećavaju u području učinkovitog pružanja multimedijalnih usluga (s prilagodivom kvalitetom i s visokom učinkovitosti spektra). U ovom radu je razmotrena mogućnost korištenja LTE signala uzlazne veze, uz korištenje kognitivne radio tehnologije, u području pokrivenom DVB-T2 signalom. Razmotrene su metode prijenosa DVB-T2 signala s jednim ulazom i jednim izlazom (eng. Single-Input Single-Output, SISO) te više ulaza i jednim izlazom (eng. Multiple-Input Single-Output, MISO). Definirani su scenariji koegzistencije i isti su izmjereni korištenjem prikladnog mjernog ispitnog stola. Kvaliteta primljenog TV signala je evaluirana na fizičkom sloju. Prikupljeni rezultati omogućuju bolje razumijevanje utjecaja LTE sustava na DVB-T2 koji koristi metodu diverzifikacije u istom radio-frekvencijskom kanalu (koegzistencija susjednog kanala). Jedan od glavnih rezultata je postojanje istih zahtjeva na proces dekodiranja s ispravljanjem pogrešaka u prijemniku (eng. Forward Error Correction) DVB-T2 prijemnika kada se neravnoteža snaga između TV predajnika (MISO i SISO režimi rada) uzima u obzir na interferirajućem LTE signalu. Navedeni rezultat potvrđen je analizom varijance

Field Measurements in Determining Incumbent Spectrum Utilization and Protection Criteria in Wireless Co-existence Studies

Studies of spectrum sharing and co-existence between different wireless communication systems are important, as the current aim is to optimize their spectrum utilization and shift from static exclusive spectrum allocation to more dynamic co-existence of different systems within same frequency bands. The main goal of this thesis is to provide measurement methodologies for obtaining realistic results in modeling incumbent spectrum utilization and in determining incumbent protection criteria. The following research questions are considered in this thesis: Q1) How should field measurements be conducted and used to model incumbent spectrum utilization? Q2) How should field measurements be conducted and used to determine protection criteria for incumbents in a co-existence scenario with mobile broadband? and Q3) Which licensing methods and technological solutions are feasible to enable spectrum sharing in frequency bands with incumbents? To answer to Q1, this thesis describes the development of a spectrum observatory network concept created through international collaboration and presents measurement methodologies, which allow to obtain realistic spectrum occupancy data over geographical areas using interference map concept. A cautious approach should be taken in making strong conclusions from previous single fixed location spectrum occupancy studies, and measurements covering larger geographical areas might be needed if the measurement results are to be used in making spectrum management decisions. The field interference measurements considered in Q2 are not covered well in the current research literature. The measurements are expensive to conduct as they require substantial human resources, test network infrastructure, professional level measurement devices and radio licenses. However, field measurements are needed to study and verify hypotheses from computer simulations or theoretical analyses in realistic operating conditions, as field measurement conditions can not or are not practical to be adequately modeled in simulations. This thesis proposes measurement methodologies to obtain realistic results from field interference measurements, taking into account the propagation environments and external sources of interference. Less expensive simulations and laboratory measurements should be used both to aid in the planning of field measurements and to complement the results obtained from field measurements. Q3 is investigated through several field interference measurement campaigns to determine incumbent protection criteria and by analyzing the spectrum observatory data to determine the occupancy and trends in incumbent spectrum utilization. The field interference measurement campaigns have been conducted in real TV White Space, LTE Supplemental Downlink and Licensed Shared Access test network environments, and the obtained measurement results have been contributed to the development of the European spectrum regulation. In addition, field measurements have been conducted to contribute to the development and technical validation of the spectrum sharing frameworks. This thesis also presents an overview of the current status and possible directions in spectrum sharing. In conclusion, no single spectrum sharing method can provide universally optimal efficiency in spectrum utilization. Thus, an appropriate spectrum sharing framework should be chosen taking into account both the spectrum utilization of the current incumbents and the future needs in wireless communications.Siirretty Doriast

Coexistence of DTT and Mobile Broadband: A Survey and Guidelines for Field Measurements

This article provides a survey and a general methodology for coexistence studies between digital terrestrial television (DTT) and mobile broadband (MBB) systems in the ultra high frequency (UHF) broadcasting band. The methodology includes characterization of relevant field measurement scenarios and gives a step-by-step guideline on how to obtain reliable field measurement results to be used in conjunction with link budget analyses, laboratory measurements, and simulations. A survey of potential European coexistence scenarios and regulatory status is given to determine feasible future use scenarios for the UHF television (TV) broadcasting band. The DTT reception system behavior and performance are also described as they greatly affect the amount of spectrum potentially available for MBB use and determine the relevant coexistence field measurement scenarios. Simulation methods used in determining broadcast protection criteria and in coexistence studies are briefly described to demonstrate how the information obtained from field measurements can be used to improve their accuracy. The presented field measurement guidelines can be applied to any DTT-MBB coexistence scenarios and to a wide range of spectrum sharing and cognitive radio system coexistence measurements.</p

5th Generation mobile networks: a new opportunity for the convergence of mobile broadband and broadcast services

© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] This article analyzes the challenges and opportunities that the upcoming definition of future 5G mobile networks brings to the mobile broadband and broadcast industries to form a single converged network. It reviews the state-of-the-art in mobile and broadcast technologies and the current trends for convergence between both industries. This article describes the requirements and functionalities that the future 5G must address in order to make an efficient and flexible cellular-broadcasting convergence. Both industries would benefit from this convergence by exploiting synergies and enabling an optimum use of spectrum based on coordinated spectrum sharing.The authors would like to thank the funding received from the Spanish Ministry of Science and Innovation within the Project number TEC2011-27723-C02-02.Calabuig Gaspar, J.; Monserrat Del Río, JF.; Gómez Barquero, D. (2015). 5th Generation mobile networks: a new opportunity for the convergence of mobile broadband and broadcast services. IEEE Communications Magazine. 53(2):198-205. https://doi.org/10.1109/MCOM.2015.7045409S19820553