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Hybrid ARQ-CQI Feedback-Based Access Scheme in Cognitive Radio Networks

In this paper, we consider a cognitive radio (CR) network where the primary network's feedback information is utilized to develop an access scheme for the secondary network to exploit the underutilized primary spectrum resources. Secondary users (SUs) identify the spectrum opportunities by sensing the spectrum for primary users (PUs) activities and by listening to the PUs feedback. The feedback signals monitored in this research work are the channel quality indicator (CQI) and automatic repeat request (ARQ) available in the PUs network. For detecting the PUs activities, SUs employ soft energy

Software and Communications

Effective area spectral efficiency metric for decode-and-forward cooperative wireless communications

In this paper, we introduce a new metric, namely: effective area spectral efficiency (EASE), to quantify the spectral efficiency as well as the spatial properties of decoding and forward (DF) relaying wireless communications networks with interference management. The EASE metric is based on the average affected area, the average ergodic capacity, and a new introduced index, namely: source relay communication index (SRCndx). We derive a closed-form expression for the maximum transmission range under Rayleigh fading environment. Based on the maximum transmission range, we define and derive the

Software and Communications

Spectrum-aggregating cognitive multi-antenna user with multiple primary users

We investigate a cognitive radio scenario involving a single cognitive transmitter equipped with K antennas sharing the spectrum with M primary users (PUs) transmitting over orthogonal bands. Each terminal has a queue to store its incoming traffic. We propose a novel protocol where the cognitive user transmits its packet over a channel formed by the aggregate of the inactive primary bands. We study the impact of the number of PUs, sensing errors, and the number of antennas on the maximum secondary stable throughput. © 2014 IEEE.

Software and Communications

Advance Artificial Intelligence Technique for Designing Double T-Shaped Monopole Antenna

Machine learning (ML) has taken the world by a tornado with its prevalent applications in automating ordinary tasks and using turbulent insights throughout scientific research and design strolls.ML is a massive area within artificial intelligence (AI) that focuses on obtaining valuable information out of data, explaining why ML has often been related to stats and data science. An advanced meta-heuristic optimization algorithm is proposed in this work for the optimization problem of antenna architecture design. The algorithm is designed, depending on the hybrid between the Sine Cosine Algorithm

Software and Communications

UAV Tracking System Using Integrated Sensor Fusion with RTK-GPS

Tracking Unmanned Aerial Vehicles (UAVs) is a significant surge in commercial or recreational use. The proposed tracking system is involved in determining the position and attitude angles of the UAVs in real-time. Data fusion of multiple sensors is one of the technologies used most in recent years and is based on real-time estimation of UAV's both position and attitude angles with high precision. In order to accomplish this objective, sensor fusion of an accelerometer, a gyroscope, a magnetometer, and a real-time kinematic global positioning system (RTK-GPS) sensors are implemented in this

Software and Communications

Achievable degrees of freedom of the K-user MISO broadcast Channel with alternating CSIT via interference creation-resurrection

Channel state information at the transmitter affects the degrees of freedom of the wireless networks. In this paper, we analyze the DoF for the K-user multiple-input single-output (MISO) broadcast channel (BC) with synergistic alternating channel state information at the transmitter (CSIT). Specifically, the CSIT of each user alternates between three states, namely, perfect CSIT (P), delayed CSIT (D) and no CSIT (N) among different time slots. For the K-user MISO BC, we show that the total achievable degrees of freedom (DoF) are given by K2/K2-1 through utilizing the synergistic benefits of

Software and Communications

Space-time coding for an energy harvesting cooperative secondary terminal

In this letter, we consider a cognitive scenario where an energy harvesting secondary user (SU) shares the channel with a primary user (PU). The SU is equipped with two antennas. It maintains a finite capacity energy queue and two infinite capacity data queues: one for storing its own data packets and the other for storing the primary undelivered data packets. The PU communicates with its destination whenever it has data at its queue head. During idle sessions of the PU, if the secondary energy queue maintains at least κ packets, the SU employs the Alamouti coding scheme over two of its data

Software and Communications

Effective area spectral efficiency for wireless communication networks with interference management

In this paper, we introduce a new metric, namely, effective area spectral efficiency (EASE), to quantify the spectral efficiency as well as the spatial properties of point-to-point transmission systems and decode and forward (DF) relaying communications networks with interference management. For each transmission mode, we derive a closed-form expression for the maximum transmission range under Rayleigh fading environment. Based on the maximum transmission range, we define and derive the average affected area and the average ergodic capacity. We then introduce the EASE expression to quantify

Software and Communications

Admission and power control for spectrum sharing cognitive radio networks

We investigate the problem of admission and power control considering a scenario where licensed, or primary, users and cognitive radios, or secondary users, are transmitting concurrently over the same band. The primary users share a common receiver and the interference on this receiver from secondary users should be strictly limited to a certain level. Each secondary link is assumed to have a minimum quality of service (QoS) requirement that should be satisfied together with the interference limit constraint, otherwise the secondary link is not admitted. Under those constraints, admission and

Software and Communications

Adaptive linearly constrained minimum variance beamforming for multiuser cooperative relaying using the kalman filter

In this paper, we consider a wireless communication scenario with multiple source-destination pairs communicating through several cooperative amplify-and-forward relay terminals. The relays are equipped with multiple antennas that receive the source signals and transmit them to the destination nodes. We develop two iterative relay beamforming algorithms that can be applied in real-time. In both algorithms, the relay beamforming matrices are jointly designed by minimizing the received power at all the destination nodes while preserving the desired signal at each destination. The first algorithm

Software and Communications