The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this work, a relay-selection scheme is proposed for underlay cognitive radio networks, with fixed and adaptive relaying power. The relay-selection and power allocation is based on the calculation of the log-likelihood ratio (LLR) value, calculated at each of the relay nodes available in the secondary network. No interference is caused to the primary network, through the satisfaction of a low power...
In our paper, a novel method is proposed to obtain the optimal positions of secondary base stations (SBSs) for cognitive radio Internet of Things (IoT) sensor networks and to select the optimal operating channel in order to maximize the secondary capacity, while also protecting the primary systems. We proposed an appearance probability matrix for secondary IoT sensor devices in order to maximize the...
In this paper, we investigate the resource allocation for the video streaming service in the cognitive radio network (CRN) based on orthogonal frequency division multiple access (OFDMA). Considering the channel estimation error between secondary transmitters (STx) and primary receivers (PRx), we address the probabilistic interference constraint model. With imperfect CSI between STx and secondary receivers...
We consider a two-way cognitive radio relay network where two secondary users (SUs) can simultaneously transfer energy and information to a relay. Then, a joint optimization algorithm for power allocation and energy cooperation is proposed. The algorithm proves that the formulated throughput maximization problem is a convex optimization problem. Next, we decompose the formulated problem into a power...
This paper investigates the resource allocation problem in heterogeneous cognitive radio networks (HCRNs). In this paper, two types of users, i.e., multi-homing and single-network cognitive radio users (CRUs), are considered to coexist in HCRNs. Multi-homing CRUs can access multiple networks simultaneously, while single-network CRUs can be served by only one network at a time. With the aim of maximizing...
Based on the problem of the multi-objective spectrum allocation on the joint optimization of maximal network utility and the fairness of users in the cognitive network, a novel adaptive fruit fly algorithm (FOA) for channel (i.e. spectrum) scheduling is proposed, which can make both of primary users (PUs) and cognitive nodes (CNs) access to the available wireless channels. In the present algorithm,...
A cognitive radio network consisting of multiple energy harvesting spectrum sensors is considered. The goal of this paper is to design an optimal sensors allocation strategy to maximize the sum detected channel availability probability. The sum detected channel availability probability maximization problem is formulated as a non-convex optimization problem. A Greedy algorithm is proposed to solve...
In this paper, a non-orthogonal multiple access cognitive radio network with simultaneous wireless information and power transfer is studied under a practical non-linear energy harvesting model. A multi-objective optimization problem(MOOP) is formulated to maximize the harvesting power of each energy harvesting receiver. This problem is non-convex and challenging to be solved. The weighted Tchebycheff...
We study a cognitive radio network in which two sources communicate with each other through multiple relays operating in non-overlapping frequency bands in the radio spectrum. We consider the problem of optimizing the transmission powers of the sources and relays so that the minimum of the two sources' transmission capacities is maximized. Thanks to the non-overlapping nature of the relays' signals,...
Cognitive radio (CR) is an effective way to improve the utilization of spectrum resource. This paper focuses on the resource allocation in cooperative relay cognitive radio networks and proposes an optimized resource allocation algorithm. In the algorithm, when the channel between the primary source and destination is good, the primary user (PU) selects a best sub-channel to transmit its data directly,...
In this correspondence, the comprehensive problem of joint power, rate, and subcarrier allocation have been investigated for enhancing the spectral efficiency of multi-user orthogonal frequency-division multiple access (OFDMA) cognitive radio (CR) networks subject to satisfying total average transmission power and aggregate interference constraints. We propose novel optimal radio resource allocation...
Cognitive radio is a promising technology to relieve the pressure of spectrum crisis with the sharp increasement of wireless services. In this paper, the game model for spectrum leasing in cognitive radio network is considered, where the Primary Transmitter(PT) will choose some Secondary Transmitter(ST) as relay to resist multi-path fading and enhance the transmission efficiency. As a reward, the...
Wireless sensor networks (WSNs) are considered as a crucial technology that will definitely ensure a permanent growth to emergent applications as smart homes, smart grids, etc. In the particular home area network (HAN) context, sensor nodes will be in charge of the power monitoring between the smart home appliances. But, the communications in WSNs generally relay on the ISM bands, characterized by...
This work investigates the downlink resource allocation (RA) problem in orthogonal frequency division multiplexing (OFDM)-based cognitive radio networks. The objective of this work is to develop a fair RA-algorithm that maximizes the capacity of secondary users (SUs) and in the same time limits the interference caused to the primary users. The fairness condition is formulated as a minimal data condition...
Wideband sensing-based cognitive radio with simultaneous wireless information and power transfer can be designed for efficient spectrum and energy usage. We investigate maxmin fairness energy-harvesting optimization problem in such a system by taking into account of the individual link fairness. In particular, we maximize the energy harvested by the worstcase link when the problem is subject to the...
In this paper, we propose an opportunistic scheduling algorithm for secondary users (SUs) in a dynamic spectrum access network. Scheduling is performed at the beginning of each super-frame where appropriate channel(s) are assigned to the SUs based on the expected throughput that each channel provides. We compute the expected throughput for each channel on specific time slots in a super-frame based...
In this paper, we study spectrum overlay access to share spectrum between primary users (PUs) and secondary users (SUs). Our goal is to maximize the average throughput by optimal power allocation within finite time duration. To do this, we formulate this optimization problem as a Markov Decision Process with continuous state. An approximate value method with pre-allocation mechanism is proposed, which...
Future communication subsystems of space exploration missions can potentially benefit from software-defined radios (SDRs) controlled by machine learning algorithms. In this paper, we propose a novel hybrid radio resource allocation management control algorithm that integrates multi-objective reinforcement learning and deep artificial neural networks. The objective is to efficiently manage communications...
In this paper, we use a Spectrum Sharing/allocation algorithm to implement a Cognitive Radio network without spectral awareness. This allows radio resources to be allocated to primary users and to secondary users in such a way that primary system and secondary system are aware of each other. By doing this, sensing of spectrum holes is avoided but the primary users will be protected and will always...
In this paper, we study a multi-level power allocation scheme for SUs in cognitive radio systems that uses a new frame structure to improve overall throughput of the system. The scheme is different from the conventional strategies in that the PU can now transmit with multiple levels of power rather than a constant level of power, which seems to be more realistic and practical. Our proposed strategy...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.