33 research outputs found
Noise properties in the ideal Kirchhoff-Law-Johnson-Noise secure communication system
In this paper we determine the noise properties needed for unconditional
security for the ideal Kirchhoff-Law-Johnson-Noise (KLJN) secure key
distribution system using simple statistical analysis. It has already been
shown using physical laws that resistors and Johnson-like noise sources provide
unconditional security. However real implementations use artificial noise
generators, therefore it is a question if other kind of noise sources and
resistor values could be used as well. We answer this question and in the same
time we provide a theoretical basis to analyze real systems as well
What kind of noise guarantees security for the Kirchhoff-Loop-Johnson-Noise key exchange?
This article is a supplement to our recent one about the analysis of the
noise properties in the Kirchhoff-Law-Johnson-Noise (KLJN) secure key exchange
system [Gingl and Mingesz, PLOS ONE 9 (2014) e96109,
doi:10.1371/journal.pone.0096109]. Here we use purely mathematical statistical
derivations to prove that only normal distribution with special scaling can
guarantee security. Our results are in agreement with earlier physical
assumptions [Kish, Phys. Lett. A 352 (2006) 178-182, doi:
10.1016/j.physleta.2005.11.062]. Furthermore, we have carried out numerical
simulations to show that the communication is clearly unsecure for improper
selection of the noise properties. Protection against attacks using time and
correlation analysis is not considered in this paper
Power spectral density estimation for wireless fluctuation enhanced gas sensor nodes
Fluctuation enhanced sensing (FES) is a promising method to improve the
selectivity and sensitivity of semiconductor and nanotechnology gas sensors.
Most measurement setups include high cost signal conditioning and data
acquisition units as well as intensive data processing. However, there are
attempts to reduce the cost and energy consumption of the hardware and to find
efficient processing methods for low cost wireless solutions. In our paper we
propose highly efficient signal processing methods to analyze the power
spectral density of fluctuations. These support the development of
ultra-low-power intelligent fluctuation enhanced wireless sensor nodes while
several further applications are also possible
Low-cost photoplethysmograph solutions using the Raspberry Pi
Photoplethysmography is a prevalent, non-invasive heart monitoring method. In
this paper an implementation of photoplethysmography on the Raspberry Pi is
presented. Two modulation techniques are discussed, which make possible to
measure these signals by the Raspberry Pi, using an external sound card as A/D
converter. Furthermore, it is shown, how can digital signal processing improve
signal quality. The presented methods can be used in low-cost cardiac function
monitoring, in telemedicine applications and in education as well, since cheap
and current hardware are used. Full documentation and open-source software for
the measurement available:
http://www.noise.inf.u-szeged.hu/Instruments/raspberryplet/Comment: 14th IEEE International Symposium on Computational Intelligence and
Informatics (CINTI 2013), November 19-21, 2013, Budapest, Hungar
Efficient Sound Card Based Experimention At Different Levels Of Natural Science Education
Sound cards, which count as standard equipment in today's computers, can be
turned into measurement tools, making experimentation very efficient and cheap.
The chief difficulties to overcome are the lack of proper hardware interfacing
and processing software. Sound-card experimentation becomes really viable only
if we demonstrate how to connect different sensors to the sound card and
provide suitable open-source software to support the experiments. In our talk,
we shall present a few applications of sound cards in measurements: photogates,
stopwatches and an example of temperature measurement and registration. We also
provide the software for these applications.Comment: MPTL-HSCI 2011 Joint conference, 15-17 September 2011, Ljubljana,
Sloveni
How accurate is an Arduino Ohmmeter?
The Arduino platform is widely used in education of physics to perform a
number of different measurements. Teachers and students can build their own
instruments using various sensors, the analogue-to-digital converter of the
Arduino board and code to calculate and display the result. In several cases
this can mean incautious reproduction of what can be found on the Internet and
an in-depth understanding can be missing. Here we thoroughly analyse a
frequently used resistance measurement method and show demonstration
experiments as well to make it clear
Current and voltage based bit errors and their combined mitigation for the Kirchhoff-law-Johnson-noise secure key exchange
We classify and analyze bit errors in the current measurement mode of the
Kirchhoff-law-Johnson-noise (KLJN) key distribution. The error probability
decays exponentially with increasing bit exchange period and fixed bandwidth,
which is similar to the error probability decay in the voltage measurement
mode. We also analyze the combination of voltage and current modes for error
removal. In this combination method, the error probability is still an
exponential function that decays with the duration of the bit exchange period,
but it has superior fidelity to the former schemes.Comment: 9 pages, accepted for publication in Journal of Computational
Electronic