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We examine the effects of imperfect phase estimation of a reference signal on the bit error rate and mutual information over a communication channel influenced by fading and thermal noise. The Two-Wave Diffuse-Power (TWDP) model is utilized for statistical characterization of propagation environment where there are two dominant line-of-sight components together with diffuse ones. We derive novel analytical expression of the Fourier series for probability density function arising from the composite received signal phase. Further, the expression for the bit error rate is presented and numerically evaluated. We develop efficient analytical, numerical and simulation methods for estimating the value of the error floor and identifying the range of acceptable signal-to-noise ratio (SNR) values in cases when the floor is present during the detection of multilevel phase-shift keying (PSK) signals. In addition, we use Monte Carlo simulations in order to evaluate the mutual information for modulation orders two, four and eight, and identify its dependence on receiver hardware imperfections under the given channel conditions. Our results expose direct correspondence between bit error rate and mutual information value on one side, and the parameters of TWDP channel, SNR and phase noise standard deviation on the other side. The results illustrate that the error floor values are strongly influenced by the phase noise when signals propagate over a TWDP channel. In addition, the phase noise considerably affects the mutual information.
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An investigation of THz backscattered side-channels measurement at a distance
This paper presents the measurement setup and the investigation on the backscatter side-channel signal detected and received, at 300Ghz, from the activated FPGA board. First, the ellipsoidal reflector, used as an incident source, with a spot size of 0.7mm is designed and fabricated. Next, a region on the FPGA chip is divided geometrically into various cells with cell dimensions corresponding to reflector spot size. Finally, it was shown that the backscatter side-channel signal can be detected by a diagonal horn antenna placed at a distance from the FPGA board. The received signal behavior is investigated in terms of absolute signal strength, measured noise power level and signal to noise ratio. This provides deeper insight into the detected backscatter side-channel emanating for the FPGA board.
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- Award ID(s):
- 1740962
- PAR ID:
- 10112669
- Date Published:
- Journal Name:
- Proceedings of the European Conference on Antennas and Propagation
- ISSN:
- 2164-3342
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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