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In this article we present a study in regards to the actualization of a phased array antenna utilizing digital beamforming. Digital beam forming comprises of the spatial permeation of a signal where the phase shifting, adding, and amplitude scaling are actualized digitally. The thought is to utilize a programmable and computational environment which forms a signal in the digital realm to supervise...
Faster-than-Nyquist (FTN) signaling was originally proposed by Mazo, which provides the opportunity of increasing data transmission rate effectively. However, this induces unavoidable ISI effects at the receiver and leads to higher receiver complexity. So far, a number of time domain equalization receiver algorithms have been proposed, which have higher demodulation complexity in FTN system with infinite...
Cognitive radio emerges as a promising technology to improve the utilization of the allocated spectrum. In a cognitive radio network, secondary users (SUs) need to sense the spectrum to obtain currently available channels and have to vacate the occupied channels when primary users (PUs) return. In cognitive radio networks, establishing a link through a common available channel is defined as the rendezvous...
To protect the high-speed integrated circuits from electrostatic discharge (ESD) damages, the ESD protection design of inductor-assisted silicon-controlled rectifier (LASCR) is investigated in this work. Compared with the conventional ESD protection design of dual-diode, the LASCR has better high-speed performances and higher ESD robustness. Therefore, the LASCR is very suitable for high-speed applications.
A distributed scheduling algorithm for millimeter wave (mmW) mesh networks is studied in this paper. The suggested algorithm starts initially with a random feasible schedule determined in a cooperative way between the nodes then tries to reach better feasible schedules via parallel and successive local search for better schedules in a defined range for each node without violating the feasibility constraints...
The performance of digital communication systems, depending on the signal modulation and demodulation. In this paper, loading several different jamming pattern to different digital communication modulation system models, the bit error rate(BER) under different conditions of jamming signal ratio(JSR) was in statistics through a large number of statistical simulation, the graph is giving to illustrate...
Wireless sensor networks (WSNs) were designed for monitoring environment that is difficult to access. The energy of each node has its limit and cannot be replaced or recharged. All components of WSNs must be an energy efficient component, not only hardware component but also software component. Energy efficient routing protocol can prolong the networks lifetime. Reactive WSNs is addressed in this...
This paper considers how selection techniques applied in an orthogonal frequency division multiplexing (OFDM)-based wireless local area network (WLAN) system influence on a system performance. Namely, ergodic and outage capacity of the considered system are simulated in order to determine the most adequate receiver design for certain WLAN environment.
The Median of Maxima Estimate (MOME) receiver is a distribution-free Constant False Alarm Rate (CFAR) receiver used to detect signal bursts against a time-varying, non-Gaussian background. Receiver configuration requires selecting four parameters that determine detection performance and adaptation rate. A semi-analytic method of determining the false alarm rate is proposed. This procedure avoids time...
Vehicles in the near future will be equipped with dedicated short-range communications (DSRC) transceiver which holds great promise of significantly reducing vehicle collisions by enabling vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications. In addition, modern vehicles will be equipped with different on-board sensors such as GPS receivers and ranging sensors (e.g., cameras,...
The number of devices enhanced with wireless communication capabilities is increasing at a fast pace. Such increase has exacerbated the quest for efficient medium access control protocols. In fact, the possibility of providing concurrent access to multiple channels, thus increasing throughput and reducing channel access delays, has been widely investigated. Among the alternatives for providing multi-channel...
This paper proposes a novel uncoded digital modulation scheme with high spectral and power efficiency, denominated 32P-3D. This scheme has a symbol constellation that consists of 32 points symmetrically distributed in a threedimensional space. The theoretical analysis and the simulations show a considerably high performance against the noise in comparison to 16-ary Quadrature Amplitude Modulation...
This paper presents a wake-up receiver (WuRx) for wireless sensor networks, which can wake up devices connected to WuRx when it receives RF signals. The proposed WuRx consists of a LC passive voltage booster at 920 MHz, a voltage multiplier and a Schmitt trigger comparator. In the simulation, the sensitivity is −30 dBm and the power consumption is 6.7 nW of the comparator. The voltage multiplier is...
A new DC cancellation technique for a mixer-first receiver in UHF RFID reader is presented in this paper. A band-pass filter composed of an inductor and a capacitor is proposed to cancel the large DC component caused by the carrier leakage at the output of the passive mixer where the mixer is the input stage of the receiver to achieve a high 1dB compression point. Simulation results indicate that...
A Loran-C system is a hyperbolic navigation system which works based on the TOA methods. The cycle identification and ECD estimation accuracies have considerable effects on the Loran-C system receivers localization accuracy so it is important to estimate the reference point and ECD as precisely as possible. White Gaussian noise degrades the performance of cycle identification and ECD estimation. Also,...
The reliability of Global Navigation Satellite System (GNSS) has been very important according to an ever-increasing dependency on GNSS in the position, navigation, and timing (PNT) applications. Nevertheless, there is still a distinctive weakness that GNSS signal is easily damaged by the jamming attack. GNSS jamming incident is considered to be an act of provocation that poses a threat to the security...
In cognitive radio (CR) networks, control channels are needed for secondary users (SUs) to perform certain handshaking procedures to negotiate communication parameters and to exchange control messages. The process of SUs attempting to meet on a channel is known as rendezvous. Previous studies either use a dedicated control channel or adopt channel-hopping schemes to rendezvous. However, it is not...
This paper presents the design and implementation of the integrated circuit aimed at pulse oximetry measurements and intended to be a part of the biomedical SoC. The basics of the noninvasive method for oxygen saturation monitoring are briefly described and then the overview of the designed chip is presented and discussed. Next, several important simulation results are shown, proving proper operation...
In this paper an enhanced version of DCSK (Differential Chaos Shift Keying) and HE-DCSK (High Efficiency Differential Chaos Shift Keying) named Very High Efficiency Differential Chaos Shift Keying system-Walsh Hadamard (VHE-DCSK-WH) is proposed. In this new system, we use N Walsh Hadamard (WH) codes to multiplex N different data bits. A single chaotic code is also used to ensure data spreading. As...
Device-free passive localization aims at locating moving objects that do not carry any localization devices. The rationale of this problem is based on the fact that a moving object can result in changes of received signal strength (RSS) of the wireless links. Existing studies only consider localization of a single-target localization or a multi-target group moving together, equivalent to a single-target...
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