Cooperative Transmission Protocol Research Articles

Advancements in Neighboring-Based Energy-Efficient Routing Protocol (NBEER) for Underwater Wireless Sensor Networks.

Underwater wireless sensor networks (UWSNs) have gained prominence in wireless sensor technology, featuring resource-limited sensor nodes deployed in challenging underwater environments. To address challenges like power consumption, network lifetime, node deployment, topology, and propagation delays, cooperative transmission protocols like co-operative (Co-UWSN) and co-operative energy-efficient routing (CEER) have been proposed. These protocols utilize broadcast capabilities and neighbor head node (NHN) selection for cooperative routing. This research introduces NBEER, a novel neighbor-based energy-efficient routing protocol tailored for UWSNs. NBEER aims to surpass the limitations of Co-UWSN and CEER by optimizing NHNS and cooperative mechanisms to achieve load balancing and enhance network performance. Through comprehensive MATLAB simulations, we evaluated NBEER against Co-UWSN and CEER, demonstrating its superior performance across various metrics. NBEER significantly maximizes end-to-end delay, reduces energy consumption, improves packet delivery ratio, extends network lifetime, and enhances total received packets analysis compared to the existing protocols.

On the outage probability of energy harvested cooperative multiuser cognitive NOMA network

AbstractThis paper investigates a multiple users cooperative cognitive non‐orthogonal multiple access (NOMA) network with energy harvesting. Primary transmitter and secondary sources serving as energy‐constrained nodes harvest energy from the power beacon PBS. In primary network, primary transmitter sends signals towards primary receiver. In order to make full use of spectrum resources, the secondary network access the licensed spectrum of primary network with overlay mode, where the best secondary source with maximum transmission signal‐to‐noise ratio between primary transmitter and secondary sources act as relays to forward signal via NOMA principle. In this context, two cooperative transmission protocols, namely, traditional NOMA cooperative transmission and adaptive NOMA cooperative transmission are proposed. For NOMA cooperative transmission, relays use NOMA to forward the superimposed signal of primary signal and secondary signal without any constrain. However, for adaptive NOMA cooperative transmission, relays use NOMA by judging whether the transmission between primary transmitter and primary receiver is successful or not. Primary receiver merges signals received from two transmission slots by selection combining. Finally, exact and asymptotic outage probability of primary network and secondary network with two cooperative transmissions are derived and simulated. It is shown that outage performance is improved for the proposed adaptive NOMA cooperative transmission.

Performance Analysis of PSDRCT-RFEH-DF in Cooperative Networks

To prolong the lifetime of energy-constrained cooperative networks, radio frequency energy harvesting (RFEH) technology can effectively solve the energy constraints of nodes batteries, and we consider the maximum ratio combining (MRC) method at the destination node to improve the reliability of the link transmission. Thus, we propose the power splitting-based double-relay cooperative transmission (PSDRCT) protocol with RFEH in the decode-and-forward (DF) mode in this study. According to the transmission process of the proposed protocol, the analytical expressions of outage probability, throughput, and energy efficiency are obtained. Numerical simulation results demonstrate that the location of the relay nodes, power allocation ratio, energy conversion efficiency, and transmission power are the key factors affecting the performance of the protocol. In addition, the proposed protocol has lower outage probability than the time switching-based double-relay cooperative transmission (TSDRCT) protocol under the same power allocation ratio and energy conversion efficiency.

Energy Efficient Multi-hop Cooperative Transmission Protocol for Large Scale Mobile Ad hoc Networks

Energy Efficient Multi-hop Cooperative Transmission Protocol for Large Scale Mobile Ad hoc Networks

Performance Analysis and Optimization of a Cooperative Transmission Protocol in NOMA-Assisted Cognitive Radio Networks with Discrete Energy Harvesting.

In this paper, we propose a spectrum-sharing protocol for a cooperative cognitive radio network based on non-orthogonal multiple access technology, where the base station (BS) transmits the superimposed signal to the primary user and secondary user with/without the assistance of a relay station (RS) by adopting the decode-and-forward technique. RS performs discrete-time energy harvesting for opportunistically cooperative transmission. If the RS harvests sufficient energy, the system performs cooperative transmission; otherwise, the system performs direct transmission. Moreover, the outage probabilities and outage capacities of both primary and secondary systems are analyzed, and the corresponding closed-form expressions are derived. In addition, one optimization problem is formulated, where our objective is to maximize the energy efficiency of the secondary system while ensuring that of the primary system exceeds or equals a threshold value. A joint optimization algorithm of power allocation at BS and RS is considered to solve the optimization problem and to realize a mutual improvement in the performance of energy efficiency for both the primary and secondary systems. The simulation results demonstrate the validity of the analysis results and prove that the proposed transmission scheme has a higher energy efficiency than the direct transmission scheme and the transmission scheme with simultaneous wireless information and power transfer technology.

Fairness-Aware Intragroup Cooperative Transmission in Wireless Powered Communication Networks

This article investigates fairness-aware transmission in a wireless powered communication network (WPCN), in which a group of adjacent users receive radio frequency energy and then cooperatively transmit information to a remote access point (AP) by using the harvested energy with time division multiple access (TDMA) scheme. Considering the constraints of practical energy harvesting electric circuits, a non-linear energy harvesting model is adopted in this paper. To guarantee both throughput fairness and signal-to-noise-ratio (SNR) fairness among users in the group, we propose a cooperative transmission protocol which contains three phases: wireless energy transmission (WET) phase, single information transmission phase and cooperative information transmission phase. Each user harvests wireless energy in WET phase, and then divides the harvested energy into two parts to be used in the rest two phases. In single information transmission phase, each user broadcasts its information to the AP and all the other users. In cooperative information transmission phase, all the users transmit information jointly to the AP. At the AP, the same signals in cooperative information transmission phase are combined with these in single information transmission phase by using maximum ratio combining (MRC) method. The common SNR of the received signals at the AP from all the users is achieved in both single information transmission phase and cooperative information transmission phase. Furthermore, the throughput fairness is achieved by common SNR and equal time allocation for information transmission at each user. Besides, we optimize the max-min throughput by joint WET time and harvested energy allocation. The optimal time allocation ratio and harvested energy allocation ratio are derived in closed forms. The cooperative diversity gain is achieved and numerical results demonstrate that the proposed protocol has low complexity and high reliability. Moreover, it also achieves a higher minimum throughput and is more energy-efficient in harsh transmission condition than other transmission protocols in the literature.

A Pipelined Cooperative Transmission Protocol for Fast and Reliable Image Delivery in Wireless Sensor Networks

Multimedia applications using wireless sensor networks often require bounds for end-to-end delay and packet loss rate in addition to energy efficiency in delivering a series of packets sliced from an image. This paper proposes a pipelined cooperative transmission (PCT) protocol for fast and reliable image delivery based on a tree topology originating from a sink, and allocation of a distinct time slot to each tree level. In this approach, if a sink needs an image from a specific multimedia node, it establishes a cooperative path such that a path node, a node on the tree path from the multimedia node to the sink, selects a cooperating node from its neighboring nodes at the same tree level. Then, the cooperating node assists its counterpart using the information obtained by means of overhearing message or data in order to forward a packet reliably to the nodes one level lower. This transmission mechanism improves the reliability of hop-by-hop transmission greatly without relying on retransmissions while making the packet move fast. Packets are transmitted in a pipelined manner using two channels such that different nodes at every other level send packets simultaneously. The proposed protocol is verified by analysis, simulation, and experiment, showing that it far outperforms the recent best approach in terms of end-to-end delay and energy consumption while achieving a high packet delivery rate.

Outage performance of double-relay cooperative transmission network with energy harvesting

The double-relay cooperative user transmission network with energy harvesting is investigated and time switching-based double-relay cooperative transmission (TSDRCT) protocol is designed in this paper. In such a system, a source node transmits information to its destination node with the help of two energy harvesting cooperative nodes. The system outage probability is analyzed and an explicit expression for the outage probability is derived for decode-and-forward (DF) relay protocols, then simulation experiments are provided. The simulation results demonstrate the accuracy of the theoretical analysis, and also show that the proposed TSDRCT with energy harvesting relay is much better than traditional non-cooperative scheme in term of outage performance, and it does not increase system energy consumption.

Improving Secrecy Outage and Throughput Performance in Two-Way Energy-Constraint Relaying Networks Under Physical Layer Security

In this paper, we propose three secrecy cooperative transmission protocols for a two-way energy-constrained relaying network in which two sources wish to exchange information with the help of multiple intermediate relays being subjected to wiretapping by multiple eavesdroppers. In the secure two-way communication (STW protocol), an energy-constrained relay is preselected via one of three investigated relay-selection strategies, which harvest the energy from the radio-frequency signals of one source and decode-and-forward the signals to another source. In secure two-way communication with network coding (STWNC protocol), the network coding technique is applied at a relay preselected via one of two investigated relay-selection strategies. In secure two-way communication with cooperative jamming and network coding (STWJNC protocol), under cooperative jamming, the network coding technique is applied at two sources and a preselected relay where a jammer-relay pair is preselected via one of two investigated selection strategies. The power-splitting receiver is applied at the energy-constrained relay for all proposed protocols. To evaluate performance, we derive new closed-form expressions for the secrecy outage probability and the throughput performance of the three protocols with the different relay and jammer-selection strategies. Our analysis is verified using Monte Carlo simulations.

Performance Characterization of Machine-to-Machine Networks With Energy Harvesting and Social-Aware Relays

In this paper, we propose a large-scale machine-to-machine (M2M) network architecture that incorporates energy harvesting and social-aware relays. The relay is powered by harvesting radio frequency energy and adopts the simultaneous wireless information and power transfer strategy. For the social aspect, a relay is conversant with only some of the communities and will only assist the data transfer of conversant sources. Moreover, for the energy harvesting and social-aware relay that assists the cooperative transmission protocol, we propose two different relay selection strategies, that is, social-aware random relay selection and social-aware best relay selection . The outage probability and network throughput of the proposed protocols are derived in a closed form using the stochastic geometry model, where the multiple M2M transmitter-receiver pairs and relays form independent homogeneous Poisson point processes, respectively. By comparing with the situation without social awareness, we find that social awareness can improve performance in some situations. The theoretical analysis is validated by extensive simulations.

A cross-layer protocol for exploiting cooperative diversity in multi-hop wireless ad hoc networks

Cooperative communication has emerged to reap the benefits of spatial diversity. To fully exploit cooperative diversity, we propose a medium access control and routing enabled cross-layer cooperative transmission (MACR-CCT) protocol for improving the performance in multi-hop wireless ad hoc networks (MWAN). Different from previous cooperative protocols that determine a receiver in one hop according to a non-cooperative routing protocol first and then select a cooperative relay, MACR-CCT selects the cooperative relay together with the receiver in one hop to exploit fully cooperative diversity, so that the receiver is selected for higher cooperative gain and closer distance to destination, and the relay is selected to achieve the better throughput performance while considering transmission error. Furthermore, considering that there are multiple source---destination pairs in MWAN, MACR-CCT takes interference mitigation into account to further improve network throughput when selecting the cooperative relay. Besides, we propose a theoretical model to analyze the throughput performance. Finally, we take advantage of simulation results to validate the effectiveness of our analytical model and show that our proposed MACR-CCT protocol can significantly outperform existing packet transmission mechanisms in terms of throughput and delay under the multi-hop multi-flow network scenario.

Outage Probability of Energy Harvesting Relay-Aided Cooperative Networks Over Rayleigh Fading Channel

Energy harvesting technique is a potential way for relay node energy supply in cooperative networks with respect to deployment flexibility and maintenance charge reduction. However, unlike traditional power source, it is intuitive that the fluctuation of harvested energy flow can degrade the benefit resulted from relay-aided cooperative transmission. To this end, this paper focuses on the performance analysis of an energy harvesting relay-aided cooperative network under slow fading channel from a perspective of outage behavior and attempts deriving the closed-form expression of outage probability of the proposed cooperative protocol. Compared with simple direct transmission protocol, it is proved that a multiplicative gain for improving system performance in terms of minimizing outage probability can be obtained by energy harvesting relay-aided cooperative transmission. In particular, if there are multiple available relay nodes around the environment or the energy-exhausted probability of relay node is small, it is very profitable to employ relay-aided cooperative transmission protocol.

Lattice-coded cooperation protocol for the half-duplex Gaussian two-way relay channel

This paper studies the Gaussian two-way relay channel (GTWRC), where two nodes exchange their messages with the help of a half-duplex relay. We investigate a cooperative transmission protocol, consisting of four phases: multiple access (MA) phase, broadcast (BC) phase, and two cooperative phases. For this setup, we propose a new transmission scheme based on superposition coding for nested lattice codes, random coding, and jointly typical decoding. This scheme divides the message of each node into two parts, referred to as satellite codeword and cloud center. Depending on the phase type, the encoder sends a linear combination of satellite codewords or cloud centers. For comparison, a rate region outer bound using a cut-set bound is provided. We show that the proposed scheme can achieve the capacity region in the high signal-to-noise ratio (SNR) regime. In addition, the achievable rate region is within 0.5 bit of the outer bound, regardless of all channel parameters. Using numerical examples, we show that our proposed scheme achieves a larger rate region than the best known 4-phase transmission strategy so far, called the Hybrid Broadcast (HBC) protocol by Kim et al. Our proposed scheme not only improves upon previous 2- and 3- and 4-phase protocols but also can perform superior at some cases to the introduced 6-phase protocol by Gong, Yue, and Wang (which has more complexity relative to our 4-phase protocol).

Network-Coding-Based Mutually Cooperative Transmission in Deep Space Communications

In deep space exploration, spacecrafts need to deliver large volume of time-insensitive scientific data to deep space station. However, power supply of spacecrafts is only from the solar energy and battery. That is to say, these spacecrafts are energy-limited. In order to reduce energy consumption, prolong the life of spacecrafts and send more data, the transmission protocol must be efficient and low-energy-waste. To achieve the aim, this paper proposes a network-coding-based mutually cooperative transmission protocol (NMCTP). Compared with the known protocols, i.e., COPE protocol and repeating transmission protocol, NMCTP can achieve higher diversity gain, and lower system outage probability.

Alternative relaying for cooperative multiple-access channels in wireless vehicular networks

In this paper, a novel spectrally efficient half-duplex cooperative transmission protocol is proposed for cooperative multiple-access channels in wireless vehicular networks, where multiple sources (vehicles) deliver messages to a common destination (roadside base station or roadside infrastructure) with the help of multiple decode-and-forward relays (roadside stations). The basic idea is to apply superposition coding at each transmitter in order to achieve the full diversity gain, where the linear zero-forcing detection is used at each relay to combat inter-relay interference. Compared to existing uplink cooperative protocols, the proposed scheme can exploit the cooperation involving both the relays and the sources. An achievable diversity-multiplexing trade-off is developed for the proposed transmission protocol. Even with strong inter-relay interference which has been ignored by many existing works, the proposed scheme can still approach the optimal multiple-input single-output upper bound. Numerical results have also been provided to demonstrate the performance of the proposed protocol.

Balancing outage performance of primary user and secondary user by relay-assisted primary transmission

In this paper, a cooperative transmission protocol for cognitive radio systems is proposed. In this protocol, the primary system comprises a transmitter (PT), a receiver (PR), and a decode-and-forward relay (Relay), while the secondary system comprises a transmitter (ST) and a receiver (SR). Both the ST and the Relay assist the transmissions of the primary users together. The outage probabilities of the primary system and the secondary system are analyzed and verified through simulations. In order to decrease outage probability of the secondary system, power allocation is performed at the ST. However, it will lead to deterioration of outage performance of the primary system. In order to guarantee outage performance of the primary system, a Relay is employed. Compared with two existing protocols, one without cooperation and the other with cooperation of the secondary system only, the proposed protocol is able to better balance outage performances of the primary system and the secondary system.

레일리 페이딩 채널을 통해 결합된 등가 이득 협력 라우팅의 에너지 효율

In this paper, we propose a multi-hop cooperative transmission protocol to obtain energy savings in static wireless networks. Each terminal in the network is equipped with a single antenna and each receiver uses equal gain combining technique (EGC) to combine received signals. We also propose a power allocation strategy which optimizes the total transmit power at each stage. Monte-Carlo simulations are presented to evaluate and compare performance of the proposed protocol with the multi-hop direct transmission (MDT) and the cooperative routing protocol proposed by Khadani [8], in terms of the average total transmit power and the average number of required stages.

모바일 애드혹 무선 네트워크에서 멀티 홉 협력 전송 프로토콜

In this paper, we propose a multi-hop cooperative transmission protocol over Rayleigh fading channels. In the proposed protocol, the multi-hop cooperative transmission is used to improve the system performance. Due to broadcast nature, we do not limit the receiving node to be only the next node, but the destination and all the nodes between the transmitting node and the destination. The proposed protocol can hence save the average transmit power, compared with multi-hop direct transmission protocol due to the skipped transmissions from some intermediate nodes or chosen relays. The proposed scheme is implemented and evaluated in mobile ad-hoc wireless networks.

Linear Detection for Cooperative Multiple-Access Transmission Protocols

In this paper, we first propose a new cooperative multiple-access transmission protocol by utilizing the cooperation among the sources and external relays. The impact of linear detection methods on the reception reliability is then investigated, whereas many existing works rely on the ideal theoretic criterion, i.e., the capacity region of the multiple-access channel. Analytical results are developed to show that, for a scenario with K users and K relays, the proposed scheme can ensure a minimal diversity gain of (K + 1) achievable for all users, whereas conventional approaches can only achieve a diversity gain of 1. Numerical results are also provided to demonstrate the performance of the proposed protocol.

언더레이 인지기술에서 양방향 릴레이 증분 협력 전송에 관한 연구

In this paper, we propose an incremental cooperative transmission protocol in two-way underlay cognitive radio networks. In the proposed protocol, two secondary sources attempt to transmit their packet to each other with help of a secondary relay under interference constraint. For performance evaluation, we derive exact closed-form expressions of average outage probability over Rayleigh fading channel. Then, we perform Monte Carlo simulations to verify the derivations. Results present that the simulation and theoretical results are in good agreement and the outage performance of the proposed protocol is better than that of two-way direct transmission protocol.