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In this paper the coverage and capacity of SigFox, LoRa, GPRS, and NB-IoT is compared using a real site deployment covering 8000 km2 in Northern Denmark. Using the existing Telenor cellular site grid it is shown that the four technologies have more than 99 % outdoor coverage, while GPRS is challenged for indoor coverage. Furthermore, the study analyzes the capacity of the four technologies assuming...
In this simulation work the coverage of GPRS, Narrowband-IoT, LoRa, and SigFox is compared in a realistic scenario, covering 7800 km2 and using Telenor's commercial 2G, 3G, and 4G deployment. The target is to evaluate which of the four technologies provides the best coverage for Internet of Things devices, which may be located deep indoor. The results show that Narrowband-IoT, having the best Maximum...
Indoor deployments for providing coverage and capacity inside buildings is an attractive option for cellular network operators as most of the traffic in today's cellular networks is generated indoors. This paper studies the benefit of indoor traffic offloading on the overall network capacity using a new method that allows assessing the network performance gains considering different levels of traffic...
In this measurement study the signal activity and power levels are measured in the European Industrial, Scientific, and Medical band 863-870 MHz in the city of Aalborg, Denmark. The target is to determine if there is any interference, which may impact deployment of Internet of Things devices. The focus is on the Low Power Wide Area technologies LoRa and SigFox. The measurements show that there is...
In this paper we analyze and discuss the coverage and capacity of Sigfox and LoRaWAN in a large scale urban environments covering 150 km$^2$ in Northern Denmark. First, the study measures and analyzes interference in the European 868 MHz license free industrial, scientific, and medical band, creating a model for the interference. The measured interference in downtown Aalborg has an occurrence rate...
It is becoming clear that 5G wireless systems will encompass frequencies from around 500 MHz all the way to around 100 GHz. To adequately assess the performance of 5G systems in these different bands, path loss (PL) models will need to be developed across this wide frequency range. The PL mod-els can roughly be broken into two categories, ones that have some anchor in physics, and ones that curve-...
With the aim of developing an automatic system to verify if facial images meet ISO/IEC 19794-5 standards and ICAO requirements, this paper proposes a robust method to detect facial features including two eye centers and four lip features. The proposed method restricts the areas where facial features are observed by using the skin color and shape characteristic of faces. Two eye centers are detected...
This paper proposes a robust blind deconvolution method for removing a uniform blur from microscopy images. For the estimation of the kernel — point spread function (PSF) — the stable edge is estimated using a fuzzy edge prediction method. Based on the estimated stable edges, optimizing a blurring objective function leads to a closed form for the estimation of a kernel and latent image. In comparison...
This paper presents key parameters including the line-of-sight (LOS) probability, large-scale path loss, and shadow fading models for the design of future fifth generation (5G) wireless communication systems in urban macro- cellular (UMa) scenarios, using the data obtained from propagation measurements at 38 GHz in Austin, US, and at 2, 10, 18, and 28 GHz in Aalborg, Denmark. A comparison of different...
This paper proposes an inter-level and intra-level deconvolution based image deblurring algorithm (ILILD) for microscopic images. Pyramid structure is used, and inter-level deconvolution is applied to estimate latent image from coarse level to fine level. The inter-level algorithm is based on total variation regularized Richardson-Lucy scheme, which can estimate latent image with artifacts suppressed...
Combining goal-oriented and use case modeling has been shown as an effective method of requirements engineering. To ensure the quality of such modeled artifacts, a conceptual foundation is needed to govern the process of determining what types of artifacts to be modeled, and how they should be specified and analyzed for 3Cs problems (completeness, consistency and correctness). However, such a foundation...
Highlight component is unavoidable in natural text images, which is caused by the effects of degradations, environment conditions, illumination and material of objects during the capture process. There are some techniques which could reduce or remove the specular regions but almost of them are effective only in simple cases which contain small and slight highlight areas. Strong specular zones, especially...
Elevation spread of departure angles (ESD) is the key parameter characterizing a 3D fast-fading channel model. 3D channel modeling is currently being studied in 3GPP to enable the development of MIMO techniques exploiting both azimuth and elevation dimensions of the channel. In this paper we use ray-tracing techniques to estimate the ESD behavior in Manhattan and Copenhagen city environments and compare...
Object detection plays an important role in autonomous video surveillance systems nowadays. Models based on the Hough Forests are widely applied, which use the local patches that vote for the object centers in images. Since these patches vote independently from each other, there is no guarantee that trees built in Hough Forests can obtain optimal parameters for the entire model. This paper proposes...
Combining goal-oriented and use case modeling has been proven to be an effective method in requirements elicitation and elaboration. However, current requirements engineering approaches generally lack reliable support for automated analysis of such modeled artifacts. To address this problem, we have developed GUITAR, a tool which delivers automated detection of incorrectness, incompleteness and inconsistency...
Requirements engineering (RE) is a coordinated effort to allow clients, users, and software engineers to jointly formulate assumptions, constraints, and goals about a software solution. However, one of the most challenging aspects of RE is the detection of inconsistencies between requirements. To address this issue, we have developed REInDetector, a knowledge-based requirements engineering tool, supporting...
The IEEE Wireless Access in Vehicular Environments (WAVE) family of standards is the leading worldwide standardisation effort in terms of Dedicated Short Range Communications (DSRC). WAVE aims at defining a common set of requirements and functionalities, in order to enable intercommunication and interoperability between nodes in a Vehicular Ad hoc Network (VANET). Despite the concept of service as...
With the aim of developing an automatic system to verify if facial images meet ISO/IEC 19794-5 standards and ICAO requirements, this paper proposes a robust image processing method to obtain information for quality evaluation step. Specifically, an adaptive background segmentation and a robust facial feature extraction (including eye centers, four lip features and chin) are proposed. In background...
In this paper, using diagonal signal repetition, we propose a high-rate groupwise space-time block code (GSTBC) which can be effectively decoded by a low-complexity successive interference cancellation (SIC) based receiver. The proposed GSTBC and SIC based receiver are jointly designed such that the diversity repetition in a GSTBC can induce the dimension expansion to suppress interfering signals...
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