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In this paper, spatial modulation (SM) technique and low density parity check code (LDPC) are combined. SM technique seems to provide transmissions speed and spectral efficiency at same levels under the low system complexity and cost compared to traditional multiple input multiple output (MIMO) transmission systems. However, SM may give high bit error rate (BER) values at low signal to noise ratios...
In this work, a fast method for vector modulation based active leakage cancellation is proposed for UHF RFID readers. The search space is narrowed by an initial phase and amplitude comparison between the reference signal and the leakage signal. The proposed method achieves up to 32% reduction in the number of search steps with up to 60 dB suppression in the leaked signal power. Moreover, the settling...
Two-dimensional (2D) modulation encoding [1] is one of the effective solutions that was used to take action with severe intertrack interference (ITI) effect in two-dimensional magnetic recording (TDMR) [2] system.
The performance of a low-complexity detection technique for OFDM-IM over the Nakagami-m fading channel has been analyzed. The orthogonal frequency-division multiplexing with index modulation (OFDM-IM) has recently been used in conjunction with the subcarriers using on-off keying modulation. The result shows improved performance in comparison with the conventional OFDM. The closed-form expression for...
In order to assist dynamic spectrum access in the cognitive radio framework, a precise real-time identification of the signals sent by either the primary or secondary users should be necessary. Orthogonal frequency-division multiplexing (OFDM) signals with and without DFT precoding are commonly adopted in the recent wireless communications standards. Therefore, the accurate classification of such...
A system capable of detecting and classifying narrowband signals transmitted over the air at radio frequency is described. The system is composed of two parts: (1) a signal detector and channelizer; (2) a radio-frequency modulation classifier. The signal detector uses an FFT for band edge detection. The channelizer uses the estimated bands and FFT vector to create a variable number of resampled time-domain...
Matrix converters (MC) can convert variable AC input to desired AC output. While a change occure in power systems i.e. a fault, loss of generation or changes in wind speed, in this study, Matrix Converters can properly improve the behavior of oscillatory system to be more stable. In this study, frequency of system is taken into consideration, frequency measurement is done by proper use of phase locked...
Ambient backscatter communications (AmBC) enables radio-frequency (RF) powered devices (e.g., tags, sensors) to modulate their information bits over ambient RF carriers in an over-the-air manner. This system, called ``modulation in the air'', thus has emerged as a promising technology for green communications and future Internet-of-Things. This paper studies the AmBC system over ambient orthogonal...
Future applications running on many-core processors with tens to hundreds of cores on a chip will require an efficient inter-core communication strategy to achieve high performance. Photonic Networks-on-Chip (PNoCs) have emerged as a promising alternative to the conventional metal based networks-on-chip due to their advantages in bandwidth density, power efficiency and propagation speed. However,...
In this paper, we propose the uplink transceiver for Subcarrier Index Modulation (SIM) OFDM in multiuser massive MIMO systems with imperfect channel state information (CSI). In the proposed scheme, the indexes of inactive subcarriers implicitly transmit information bits and the subcarriers activation process is only dependent on modulation order of M-QAM. To mitigate multiuser interference at the...
Non-orthogonal multiple access as a promising technology is expected to support massive connectivity in the next generation. In this paper, we propose a novel perfect energy spread transform (P-EST) based multiple access scheme, which perfectly spreads a symbol energy all over the frequency-domain and time-domain increasing the diversity gain of the system. The parameters of the proposed scheme can...
We are currently developing a dual-particle imager based on the rotational modulation collimator (RMC) technique employing Cs2LiYCl6:Ce (CLYC) detector. A symmetric mask design has been conventionally used for RMC, however, it has an intrinsic problem of not being able to distinguish two symmetric sources located with respect to the rotation axis. In the present study, we propose a new design of collimator...
Compressive THz imaging holds the potential for increased spatial resolution and imaging speed when only a small number of detectors is available. The understanding of illumination patterns is essential in determining the performance for a compressive imaging setup. The results presented here start with an evaluation of the performance of different mask types. Then the influence of deviations of the...
In this work the complete system for THz measurements is presented and briefly described. Proposed solution allows to avoid the most important disadvantages of the lock-in technique without compromising the noise parameters of the developed readout system. The prototype, designed and tested by the authors, supports the pixel line of FET-based THz detectors. The system consists of the hardware part...
A noise-efficient readout interface designed in a 150nm standard CMOS technology for a FET based THz radiation detector is presented. The interface is able to detect μV-range rectified signal from the FET detector, amplifying it by 70 dB gain. A multistage switched-capacitor (SC) readout channel employing chopper modulation is exploited so as to remove 1/ƒ noise and obtain repeatable gain and frequency...
This paper presents development of the integrated multi-channel readout circuit targeted to support the pixel-line of FET-based THz-detectors. The authors discuss architecture details and design techniques used to address the most important issues related to the processing of very small, low-frequency signals. The effectiveness of the 1/f noise component minimization and crosstalk cancellation, proven...
Space shift keying (SSK) modulation is a scheme in which the indices of active transmit antennas play an essential role in carrying information bits. In SSK modulation, the communication channel acts as modulating unit. Therefore, using the conventional relay selection schemes based on channel coefficients are impossible in cooperative systems using SSK modulation. In this paper, we propose a novel...
Polar codes are proven capacity-achieving and are shown to have equivalent or even better finite length performance than turbo/LDPC codes under some improved decoding algorithm over the Additive White Gaussian Noise (AWGN) channels. Polar coding is based on the so-called channel polarization phenomenon induced by a transform over the underlying binary-input channel. The channel polarization is found...
The Thermal Sigma-Delta (TΣΔ) modulator is a thermal-electric system where the resistive element performs in the thermal domain part of the ΣΔ modulator (sum and integration). In this work, we propose the modeling and we perform simulations of 1st and 2nd order TΣΔ modulators using bolometers as the thermal-electric device. This study has the purpose of achieving a complete solution of a bolometer...
This Paper presents a highly-applicable supply modulator (SM) for WCDMA envelope tracking power amplifier (ET PA) system. An on-chip highly-linear envelope detector is employed so that no extra envelope signal from baseband is needed. The proposed SM chip reduces the complexity of ET technique application. It can be directly employed in transmitters without using other programming or elements. It...
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