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This contribution is about the design of an image compression scheme for near loss-less image compression of a restricted class of images and a specific application. The images are digital diagnostic X-ray images of the coronary vessels of the human heart. This paper proposes a novel compression scheme with a compression ratio of 8–10 with preservation of the diagnostic image quality. Central in our...
This paper presents a new approach for dynamic spectrum management for heterogeneous wireless devices. Local congestion degrades the reliability of wireless applications in the License Exempt bands. This leads to the research questions: (1) how to realize equal spectrum sharing between dissimilar systems, and (2) how to improve the collective spectrum efficiency. A solution is in dynamic distribution...
An extensive propagation measurement survey was performed between The Netherlands and the United Kingdom. Seven mixed land/sea paths were monitored simultaneously, with path lengths ranging from 55 to 370 km. Eight frequencies between 500 and 700 MHz were used. Over 21 million measurements were collected during 500 days. This paper describes the survey and actions taken to assure high data quality...
In this paper, we propose an energy-efficient error correction scheme to lower the power consumption of the ADCs in the OFDM system. The proposed opportunistic error correction scheme is based on resolution adaptive ADCs and fountain codes. The key idea is to reduce the dynamic range of the channel by discarding part of the channel in deep fading. Correspondingly, the power consumption in ADCs can...
In this paper we present results of the new monitoring network for spectrum governance. The network is based on the RFeye system of CRFS where the data is collected employing mobile monitoring vehicles. The measurement data, obtained from a frequency sweep between 10 MHz and 6 GHz, is further analyzed. For this purpose a tool is made, tailored for the needs of the spectrum regulator. Initial results...
In wireless OFDM-based systems, coding jointly over all the sub-carriers simultaneously performs better than coding separately per sub-carrier. However, the joint coding is not always optimal because its achievable channel capacity (i.e. the maximum data rate) is inversely proportional to the dynamic range of the channel. In this paper, we propose a novel cross coding scheme to increase the maximum...
In coronary angiography the flow can be assessed by tracking the contrast agent in the image sequence. The contrast flow is used to estimate the functional behavior of the coronary arteries using TIMI frame count (TFC). In this paper we propose and evaluate a method towards the automation of TFC. The method creates a two dimensional map of the contrast agent in which the opacification of the vessel...
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