Channel-based key generation for encrypted body-worn wireless sensor networks

Body-worn sensor networks are important for rescue-workers, medical and many other applications. Sensitive data are often transmitted over such a network, motivating the need for encryption. Body-worn sensor networks are deployed in conditions where the wireless communication channel varies dramatically due to fading and shadowing, which is considered a disadvantage for communication. Interestingly, these channel variations can be employed to extract a common encryption key at both sides of the link. Legitimate users share a unique physical channel and the variations thereof provide data series on both sides of the link, with highly correlated values. An eavesdropper, however, does not share this physical channel and cannot extract the same information when intercepting the signals. This paper documents a practical wearable communication system implementing channel-based key generation, including an implementation and a measurement campaign comprising indoor as well as outdoor measurements. The results provide insight into the performance of channel-based key generation in realistic practical conditions. Employing a process known as key reconciliation, error free keys are generated in all tested scenarios. The key-generation system is computationally simple and therefore compatible with the low-power micro controllers and low-data rate transmissions commonly used in wireless sensor networks

Benchmarking Cerebellar Control

Cerebellar models have long been advocated as viable models for robot dynamics control. Building on an increasing insight in and knowledge of the biological cerebellum, many models have been greatly refined, of which some computational models have emerged with useful properties with respect to robot dynamics control. Looking at the application side, however, there is a totally different picture. Not only is there not one robot on the market which uses anything remotely connected with cerebellar control, but even in research labs most testbeds for cerebellar models are restricted to toy problems. Such applications hardly ever exceed the complexity of a 2 DoF simulated robot arm; a task which is hardly representative for the field of robotics, or relates to realistic applications. In order to bring the amalgamation of the two fields forwards, we advocate the use of a set of robotics benchmarks, on which existing and new computational cerebellar models can be comparatively tested. It is clear that the traditional approach to solve robotics dynamics loses ground with the advancing complexity of robotic structures; there is a desire for adaptive methods which can compete as traditional control methods do for traditional robots. In this paper we try to lay down the successes and problems in the fields of cerebellar modelling as well as robot dynamics control. By analyzing the common ground, a set of benchmarks is suggested which may serve as typical robot applications for cerebellar models

Preemptive search and R&D clustering revisited.

The results obtained by Cardon and Sasaki (1998) on R&D clustering are derived under the specific assumption that firms only can own one patent. When multiple patents are allowed, R&D clustering will come about more frequently if search costs are substantial.R&D clustering; Persistence of monopoly;

Realization and MIMO-link measurements of a transmit module for spatial modulation

This paper describes the realization of a circuit that transmits a data stream, through spatial modulation in the 2.45 GHz frequency band. The development of the transmitter includes RF circuit design with components such as a PLL synthesizer, Tx-DAC and IQ-modulator. A microcontroller, integrated into the circuit and programmed in C, is at the heart of the system. In this hardware system, developed specifically for spatial modulation, data is BPSK modulated and transmitted through an RF switch connected to two antennas. It can differ for every symbol which antenna is used, according to an extra series of information bits that are to be transmitted. Here the number of the selected antenna encodes the extra information bit per symbol, which not only results in a doubling of the data rate but also realizes diversity. Spatial modulation allows these features with only a single hardware transmit chain, resulting in low-cost and low-complexity hardware. At the receiving side, the extra information bits are decoded by assessing the channel used for each symbol. This practical system has been thoroughly tested by means of different measuring campaigns. The measurement results show that spatial modulation is correctly demodulated at the receiving side and forms an effective way to realize affordable MIMO systems

Teaching electronics-ICT : from focus and structure to practical realizations

We present a four-year electronics-ICT educational master program at Ghent University in Belgium. The students develop knowledge and skills from novice to experienced electronic circuit designers. In the corresponding topics, the immersion into engineering problems is deepened. The horizontal and vertical alignment of courses in the four-year master program at our university is discussed. The curriculum of the four-year master program is highly projectoriented and all topics are clustered around a well-considered set of standards. This clustering supports the logical structure of the program, with students gradually acquiring the necessary competences. All standards and their mutual interaction are extensively discussed in the paper. We also focus on four design-implement projects included in the electronics-ICT program, explicitly following CDIO-guidelines. Whereas the first-year project has a limited level of difficulty, the challenges increase significantly in the course of the next years. Students learn that product design is an iterative process on different levels, where the design strategy can be changed continuously based on important and crucial feedback. Different evaluations have demonstrated that our students are not only aware of CDIO-principles, but are also convinced of the quality of the results obtained by following the standards