Electromagnetic Compatibility Studies: LTE BS vs. Aeronautical Radionavigation Services in 694-790 MHz Frequency Band

This paper presents the sharing analysis of the 694–790 MHz frequency band for Mobile services IMT and Aeronautical radio-navigation services (ARNS) using SEAMCAT (established by CEPT) software based on the statistical simulation (Monte-Carlo) method. In 2012 the World Radiocommunication Conference (WRC-12) decided to allocate the 694–790 MHz frequency band (the so-called 700 MHz band) to mobile services IMT (excluding aeronautical mobile) after WRC-15 conference. But this agreement raises electromagnetic compatibility problems, which should be solved until WRC-15 [1]. This study was carried out in two phases: first applying theoretical analysis, then statistical Monte-Carlo simulations with SEAMCAT software tool in order to verify results obtained in theoretical approach. Analytical calculations shows that the required protection distances between ARNS stations and the MS base stations are 132 km. The obtained results from SEAMCAT simulations indicate that separation distance should be above 100 km. These results illustrate that the systems are not electromagnetically compatible. The possible mitigation technic could be antenna pattern correction

Assessment of DVB-T Compatibility with LTE in Adjacent Channels in 700 MHz Band

The 2012 World Radiocommunication Conference allocated the 694 MHz 790 MHz (700 MHz) band to the International Telecommunication Union Region 1, which includes also Europe, for the mobile service on a co-primary basis with other services to which this band is allocated on a primary basis, and was identified to the International Mobile Telecommunications. However, countries of Region 1 will also be able to continue the use of these frequencies for their digital terrestrial television services, if necessary. This allocation will be effective immediately after the 2015 World Radiocommunication Conference. The objective of this paper is to assess the electromagnetic compatibility of Digital Video Broadcasting - Terrestrial operating below 694 MHz and mobile broadband (LTE) operating in 700 MHz band. The Minimum Coupling Loss method and Monte Carlo simulation within SEAMCAT software was used for interference analysis. An adjacent channel scenario between Digital Video Broadcasting - Terrestrial and LTE was performed to evaluate the impact of Digital Video Broadcasting - Terrestrial on LTE systems. The results obtained provide the minimum coupling distance required between Digital Video Broadcasting - Terrestrial and LTE in the 700 MHz band to maintain the necessary performance level of the LTE system

Evaluation of LTE and Aeronautical Radionavigation Service Electromagnetic Compatibility in 694–790 MHz Frequency Band

In 2012 the 694-790 MHz (700 MHz) band was allocated to the International Telecommunication Union (ITU) Region 1 for mobile service (excluding aeronautical mobile), and was identified to the International Mobile Telecommunications (IMT). However, countries of Region 1 listed in Radio Regulations footnote No. 5.312 will also be able to continue using of these frequencies for their aeronautical radionavigation service (ARNS). This allocation comes into force immediately after the 2015 World Radiocommunication Conference (WRC-15). The objective of this article is to assess the electromagnetic compatibility of aeronautical radionavigation service and mobile service operating in 694-790 MHz. For interference analysis the Minimum Coupling Loss (MCL) method and Monte Carlo method simulation was used. The obtained results provide the minimum coupling distance required between ARNS and mobile service Long Term Evolution (LTE) stations to maintain the required performance level of the ARNS systems

Evaluation of LTE 700 and DVB-T Electromagnetic Compatibility in Adjacent Frequency Bands

The 2012 World Radiocommunication Conference allocated the 694-790 MHz (700 MHz) band for the mobile service on a co-primary basis with other services in Region 1 (Europe, Africa, the Middle East). However, countries of Region 1 will also be able to continue the use of these frequencies for their digital terrestrial television services, if necessary. This allocation will be effective immediately after the WRC-15. The objective of this paper is to assess the electromagnetic compatibility of Digital Video Broadcasting - Terrestrial (DVB-T) operating below 694 MHz and mobile broadband (LTE) operating in 700 MHz band. The study contains an assumption of a preferred frequency division duplex (FDD) channelling arrangement which contains confined 2x30 MHz block: 703-733 MHz (uplink) and 758-788 MHz (downlink). The model consists of two elements, a LTE network and a DVB-T system. An adjacent channel scenario was analyzed in this paper: possible impact of LTE user equipment (uplink) to DVB-T receiver. The Minimum Coupling Loss method and Monte Carlo simulation within SEAMCAT software was used for interference analysis. The Minimum Coupling Loss method was chosen to calculate worst case (most conservative scenario) in order to understand most critical points of these two systems. The Monte Carlo simulations show more relaxed electromagnetic compatibility scenario. During simulations more appropriate propagation model was used (Recommendation ITU-R P.1546), which allows to analyse also non line of sight radio propagation conditions. The results obtained provide the minimum coupling distance required between LTE and DVB-T in the 700 MHz band to maintain the necessary performance level of the DVB-T system

Analysis on Interference Impact of Wi-Fi on Digital Terrestrial Television Broadcasting

Transition from Analogue Terrestrial Television Broadcasting to Digital Terrestrial Television Broadcasting (DTTB) in the 470-862 MHz band made available amount of spectrum so-called digital dividend for other services i.e. 790-862 MHz band (800 MHz) to mobile service. Recently the 694-790 MHz band (700 MHz) was also allocated to mobile service in ITU Region 1. Spectrum allocated to a broadcasting service but not used locally is called as TV white spaces (TVWS). It is possible to introduce TVWS services in 470-790 MHz band under the condition that other services in this band already operating, or planned in the country and in neighboring countries, are adequately protected and this use does not violate the current ITU Radio Regulations. TVWS under some conditions locally could be used for mobile communications systems e.g. unlicensed Wireless Fidelity (Wi-Fi) using cognitive radio. As TVWS are located in the UHF band, the use of TVWS can provide significantly better coverage and wall penetration inside buildings than 2.4 GHz and 5 GHz range Wi-Fi frequencies. The exact amount of available spectrum for TVWS at any location will be dependent upon each country national situation e.g. DTTB planning configuration, other services use in the band. In case of deploying Wi-Fi in the TVWS the interference impact of Wi-Fi on DTTB has to be taken into account. The aim of this paper is to analyze the interference impact of Wi-Fi on DTTB. In this paper the interference occurring probability in DTTB receiver was evaluated by using Spectrum Engineering Advanced Monte-Carlo Analysis Tool (SEAMCAT)

3D photografting with aromatic azides: A comparison between three-photon and two-photon case

The final publication is available via https://doi.org/10.1016/j.optmat.2013.04.007.Photografting is a method utilizing light activation for covalent incorporation of functional molecules to a polymer surface or polymer matrix. It has been widely applied as a simple and versatile method for tailoring physical–chemical properties of various surfaces. Grafting induced via multi-photon absorption provides additional advantages of spatial and temporal control of the process. Here, a novel fluoroaryl azide photografting compound (AFA) was synthesized and compared with the commercially available azide BAC-M. Using Z-scan technique, it was determined that AFA is a two-photon absorber at 798 nm, whereas BAC-M is a three-photon absorber at this wavelength. Both azides were employed for 3D photografting within a PEG-based matrix using femtosecond laser pulses. Both Z-scan measurements and 3D photografting tests indicated that, the intensity threshold for nonlinear absorption and photografting process is lower for AFA. As a result the processing window of AFA is much broader than that of BACM. But on the other hand, since BAC-M is characterized by the three-photon absorption (3PA) process, patterns with finer features can be produced using this molecule. The choice of the appropriate compound for 3D grafting will depend on the final application and the requirements associated with the resolution and post-modification protocol

Bulk Milk Tank Samples Are Suitable to Assess Circulation of Tick-Borne Encephalitis Virus in High Endemic Areas

A reliable surveillance strategy of tick-borne encephalitis virus (TBEV) is necessary to ensure adequate disease control measures. However, current approaches assessing geographical TBEV circulation are ineffective or have significant limitations. In this study we investigated a total of 1363 goat and 312 sheep bulk tank milk samples for the presence of TBEV. Samples were collected from systematically selected farms in Lithuania every 4–5 days from April to November in 2018 and 2019. To validate results, we additionally tested 2685 questing ticks collected in the vicinity of milk collection sites. We found 4.25% (95% CI 3.25–5.47) and 4.48% (95% CI 2.47–7.41) goat and sheep milk samples to be positive for TBEV, respectively. Furthermore, geographical distribution of TBEV in milk samples coincided with the known TBE endemic zone and was correlated with incidence of TBE in humans in 2019. When sampling time coincides, TBEV detection in milk samples is as good a method as via flagged ticks, however bulk milk samples can be easier to obtain more frequently and regularly than tick samples. The minimal infectious rate (MIR) in ticks was 0.34% (CI 95% 0.15–0.64). Therefore, our results confirm that testing milk serves as a valuable tool to investigate the spatial distribution of TBEV at higher resolution and lower cost