This paper presents several signal processing approaches in Trojan detection problem in very large scale integrated circuits. Specifically wavelet transforms spectrograms and neural networks are used to analyze power side-channel signals. Trojans in integrated circuits can try to hide themselves and become almost invisible due to process and measurement noises. We demonstrate that our initial results with these techniques are promising in successful detection. Discrete wavelet transforms and ...

This paper presents the effects of channel estimation errors on the performance especially diversity gain of space-time coded systems with antenna selection. We consider maximum signal to noise ratio as the antenna selection criteria. Specifically we first present the effect on the upper bound for pairwise error probability of space-time coded systems with antenna selection over flat fading channels. Moreover we provide simulation results for the antenna selection at the receiver and/or transmitter ...

In this paper we present a cooperative communication system employing maximum ratio transmission technique and its outage probability performance over Rayleigh fading channels. Since maximum ratio transmission can achieve full diversity when used at tranmitters having multiple antennas while requiring no complexity increase at the receiver the proposed system can be a preferable structure to be used both at the source and amplify-forward type relays of wireless networks to provide high speed and ...

In this paper we investigate the performance of an amplify-and-forward multi-input multi-output two way relay network where two sources are equipped with multiple antennas employing maximal ratio transmission and the communication is carried through the selected relay resulting in the largest received power. Assuming the fading channel coefficients are Nakagami-m distributed we derive the sum symbol error rate (SSER) outage probabilities for each user and the overall system. In addition diversity ...

This paper presents a performance analysis of space-time coded systems with transmit antenna selection over frequency selective fading channels when the erroneously estimated fading coefficients are available only at the receiver. An upper bound on the pairwise error probability is derived and numerical examples are presented. The analysis does not assume any specific coding or channel estimation algorithm. With imperfect channel state information (CSI) used both at the antenna selection and the ...

In this paper the performance of the low complexity modified stack equalizer over frequency-selective fading channels is inspected. With the help of simulation results it is illustrated that by sacrificing the computational complexity insignificantly the performance of the modified equalizer can be made closer to optimum. This equalizer can be used at the receiver of uncoded systems or bit interleaved coded systems with iterative receivers.

This letter considers the effect of channel estimation errors on the performance of space-time coded (STC) systems with transmit and receive antenna selection over quasi-static flat fading channels. By performing pairwise error probability analysis and presenting numerical examples we show that the diversity order achieved with perfect channel state information (CSI) is still achievable with imperfect CSI used both at the antenna selection and the space-time decoding processes. We note that our ...

In this paper antenna selection both at the transmitter and the receiver is proposed for space-time coded (STC) orthogonal frequency division multiplexing (OFDM) systems. Antennas for all-subcarriers or per-subcarrier are selected to maximize the signal to noise ratio (SNR) at the receiver which knows the channel state information perfectly and the transmitter only knows the indices of the selected antennas. The error performance is evaluated via simulations when space time block and concatenated ...

This paper studies performance of space-time coded (STC) systems with joint transmit and receive antenna selection over multiple input multiple output (MIMO) flat and frequency-selective (FS) fading channels. Specifically we first perform a pairwise error probability analysis over flat fading channels explicitly. Then we comment on our expectations for the case of FS fading channels. We show that the joint transmit and receive antenna selection based on received power levels does not degrade the ...