Cooperative Network Coding Research Articles

Adaptive Combined Channel Network Coding for Cognitive Radio Networks with Cooperative Relay

Cognitive radio is one of the new technologies for 4G/5G applications, so cooperative relay communication and network coding are considered as certain methods to help improve their re-spective applications. A primary broadcast system for multimedia video streaming applications that broad¬casts data to primary users and an auxiliary cooperative relay secondary cognitive ra-dio system are considered. The secondary cooperative overlay system can use multiple error control coding methods for point-to-point data retransmission, such as channel coding, network coding, and combi¬ned coding methods to improve system performance under variable link con-ditions. A new technique of adaptive coding of AC2NC combined channel network for data re-transmission is proposed. The new AC2NC first analyzes the channel feedback information and then selects the best retransmission coding technique based on the target bandwidth or trans-mission time optimization. This is instead of using a single static channel or a network coding technique with dynamic channel conditions. The proposed AC2NC improves system through-put, reduces retransmission time, and provides more spectrum access opportunities for the sec-ondary sys¬tem's own data transmissions. AC2NC's relative throughput and time saving capabil-ities for cognitive radio users have been shown to exceed ninety percent, under certain channel conditions, compared to some static coding methods.

Network-Coded Cooperative Systems in Cognitive Radio Networks

We study the performance of a network-coded cooperative (NCC) system in an underlay cognitive radio network (CRN). The primary network (PN) consists of a single transmitter-receiver pair, and the secondary network (SN) is an NCC system with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$N$ </tex-math></inline-formula> users, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$M$ </tex-math></inline-formula> relays, and a single destination. The relays employ decode-and-forward (DF) protocol and use network coding (NC). We study the performance of the SN under two types of power constraints: i) the combined peak interference power constraint on the PN and maximum transmit power constraint at the SN; and ii) the single peak interference power constraint on the PN. For the SN, an exact closed-form expression and an asymptotically tight end-to-end outage probability are derived, and the diversity order and coding gain are quantified. Compared to the existing literature, the proposed CRN NCC has four main distinguishable features: i) it applies to general CRN NCC network settings with an arbitrary number of users and relays; ii) it considers general relay selection mechanism and independent and non-identically distributed (i.n.i.d.) <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Nakagami-m$ </tex-math></inline-formula> fading channels; iii) it assumes secondary-to-primary and primary-to-secondary interference links; and iv) it provides a generalization of previous work and includes existing results in the literature as special cases.

Analysis of Drone Assisted Network Coded Cooperation for LoS Environments

Analysis of Drone Assisted Network Coded Cooperation for LoS Environments

Network-Coded Cooperative LoRa Network With D2D Communication

We evaluate the outage probability and the energy efficiency (EE) of a LoRa network when the end-devices (EDs) are capable of exchanging messages with a device-to-device (D2D) technology. Our proposal is to assess the performance of the network when operating under the concept of network-coded cooperation (NCC), where the EDs are capable of transmitting linear combinations of more than one frame (including frames of another ED), performed over a non-binary finite field. We consider both connection and collision probabilities when modelling the outage probability of an ED, as well as a realistic power consumption model to evaluate the EE. Our results indicate that the proposed scheme, which we refer to as NCC-LoRa, provides considerable gains in terms of both outage probability and EE when compared to a regular LoRa network, even when considering the additional consumption of D2D communication.

Cross Layer MAC Protocol for a Peer Conscious Opportunistic Network Coded Cooperation System

This paper presents a peer conscious opportunistic network coded cooperation (PC-O-NCC) system that exploits multi-user diversity (MUD) gain in a simple network coded cooperation (NCC) based network. It prioritizes sources with better channel conditions by granting them earlier access than the other competing nodes unlike the prevalent time division multiple access (TDMA) technique used widely in any NCC network. This improves the outage performance of the overall system. To prioritise sources with better channel conditions, a novel timer-based MAC protocol is proposed. The proposed protocol is designed such that it aims to reduce collisions by taking the network load into account along with channel conditions while generating the timer values. It also minimizes the power consumption in performing clear channel assessment (CCA) by sources which is a costly affair for battery-operated devices. The simulation results show that the proposed algorithm improves the outage performance while keeping the latency to a minimum value. The improvement in the outage performance can prove to be important in taking key decisions which becomes crucial in disaster management, drone assisted scenarios or intelligent transportation systems.

Power efficient mobile small cell placement for network-coded cooperation in UDNs

Ultra-dense Networks (UDNs) massively populate areas with base stations of diverse capabilities, thus increasing the network capacity. Moreover, the radio access network (RAN) architecture moves towards small infrastructure elements such as mobile small cells (MSCs). In this context, Network-coded Cooperation (NCC) leverages the interplay between network coding and cooperative relaying to reliably offload cellular traffic to MSCs and reduce the power consumption in the network. Despite the research done separately on NCC and smart MSC deployment, there is a scarceness of works addressing the smart and on-demand deployment, activation, and deactivation of MSCs to leverage the benefits of both NCC and MSCs. To fill this gap, in this paper, we: (1) estimate the traffic density of New York by adopting an urban zoning (UZ) model; (2) provide a methodology for the on-demand deployment of base stations and MSCs according to a stochastic geometry model; (3) propose two radio resource management (RRM) models, one random and one smart, for the placement and on-demand creation of MSCs, and (4) compare the power consumption of the proposed architecture with 4G edge computing. The results show that the smart RRM model overperforms the random model five-fold in terms of number of pico base stations required, which impact on the power consumed in the network. Moreover, the results show that the smart model achieves between 6%–25% power savings in comparison to 4G edge computing, the random model, and two approaches form the related work, respectively.

Dr. Wenjing Lou, Virginia Tech, USA

Dr. Wenjing Lou is currently the W. C. English Endowed Professor of Computer Science at Virginia Tech and a Fellow of the IEEE. Her research interests span many topics in the fields of wireless networks and cybersecurity. On wireless networks, her interests lie in distributed algorithms and lightweight protocols for wireless networks. Her previous works include algorithm and protocol design for ad hoc networks, multihop cooperative communications, opportunistic routing, and network coding. She has recently collaborated with other colleagues on interference cancellation, MIMO networks, and dynamic spectrum sharing, and 5G wireless communications. On cybersecurity, she has worked on many security and privacy topics in networked information systems, including anonymous authentication, encryption-based information access control and sharing, search over encrypted data, and confidential data computation. More recently, she has been working on block-chain and decentralized consensus protocols, securing 5G/nextG mobile networks, and adversarial machine learning and trustworthy AI systems. Her research goal is to develop innovative solutions to address fundamental research challenges in emerging technologies and critical infrastructures.

Bit and Packet Error Rate evaluations for Half-Cycle stage cooperation on 6G wireless networks

The excellent features of the sixth generation (6G) of wireless technology enthuses researchers to apply advanced and complex techniques on mobile communication networks, which is what this paper explores. As a result of the ability of 6G to exchange vast data rates and network programming, the Cooperative Network Coding (CoNC) technique can be implemented to improve the connectivity and diversity within 6G applications.Though CoNC is usually implemented at the second stage, this paper proposes dividing the first stage into two Half-Cycle stages, and then applying CoNC at the second Half-Cycle stage. The resulting Bit Error Rate (BER) behaviour is investigated on the physical layer for direct data exchange in 6G local mobile networks over an Additive White Gaussian Noise (AWGN) channel. Partial Unit Turbo Code (PUTC) (4,2,1,4) and (8,4,3,8) are used by each mobile node as the forward error correction technique, which means that each mobile acts as a Base Station (BS) for other mobiles in the local network by applying CoNC on the received packets, and then each mobile node (or BS), either Amplify-and-Forward (AF), or Decode-re-encode-amplify and Forward (DF), acts. When full connectivity is not achieved at the end of the first two Half-Cycle stages, new Half-Cycle stage transmissions follow, and the BER behaviour for all additional Half-Cycle stages is obtained. The results illustrate that applying CoNC at the second Half-Cycle stage of the first general stage produces a limited BER loss. To mitigate the damage in the BER, a soft-decision PUMTC decoder is also proposed.

Network-Coded Cooperative Systems With Generalized User-Relay Selection

We consider a network-coded cooperative (NCC) system that consists of N ≥ 2 sources, M ≥ 1 decode- and-forward (DF) relays, and a single destination. The relays perform network coding (NC) on the received sources' symbols using maximum distance separable (MDS) codes. For this system, we propose the most generalized user-relay selection (GURS) scheme in the literature that selects any arbitrary subsets of K users and any arbitrary subsets of L relays subject to practical constraints such as load balancing conditions and scheduling policy. Our analytical results and design guidelines generalize and subsume all existing results as special cases. To this end, we derive a new closed-form outage probability (OP) expression, assuming non-identically and independently distributed (n.i.i.d.) Rayleigh fading channels. The asymptotic outage expression at high signal-to-noise ratio (SNR) regime is further derived, based on which, the achievable diversity order and coding gain are quantified. The theoretical derivations are also validated through Monte-Carlo simulation.

Outage Performance of Downlink Full-Duplex Network-Coded Cooperative NOMA

This letter studies the impact of network-coded multiple access (NCMA) on the outage performance of full-duplex cooperative non-orthogonal multiple access (NOMA). In particular, we propose a network-coded cooperative NOMA (NC-CNOMA) strategy, under which user devices utilize physical-layer network coding (PNC) to demodulate signals with greater probability. The exact analytical expression of the outage probability is derived to evaluate the performance of the proposed scheme. The provided simulation results validate our analysis and the proposed NC-CNOMA scheme outperforms the conventional cooperative NOMA with regard to outage performance.

Combining Non-orthogonal Transmission with Network-Coded Cooperation: Performance Analysis Over Nakagami-m Fading Channels

This paper investigates efficient transmission design in a class of multi-user cooperation networks, in which multiple information sources intend to distribute their messages to a sufficient proportion of ambient destinations with the assistance of multiple relays. We apply a relaying scheme that combines non-orthogonal transmission with network coding techniques to balance channel consumption and inter-user interference. The sources and relays are divided into clusters, terminals within each of which are allowed to non-orthogonally access the same channel. A class of finite-field network codes are adopted in the relays. We provide the methods to derive the system transmission error probability and diversity-multiplexing tradeoff (DMT), over Nakagami- $m$ fading channels. Through error probability and finite-SNR DMT analysis for certain clustering strategies, and infinite-SNR DMT analysis for general situations, we show that the considered relaying scheme can notably improve system performance over the conventional approach that demands only orthogonal transmission in network-coded cooperation networks.

Network-Coded Cooperation and Multi-Connectivity for Massive Content Delivery

Massive content delivery is in the spotlight of the research community as both data traffic and the number of connected mobile devices are increasing at an incredibly fast pace. The enhanced mobile broadband (eMBB) is one of the main use cases for the fifth generation of mobile networks (5G), which focuses on transmitting greater amounts of data at higher data rates than in the previous generations, but also on increasing the area capacity (given in bits per second per square meter) and reliability. However, the broadcast and multicast implementation in 5G and presents several drawbacks such as unexpected disconnections and the lack of device-specific QoS guarantees. As a result, whenever the exact same content is to be delivered to numerous mobile devices simultaneously, this content must be replicated. Hence, the same number of parallel unicast sessions as users are needed. Therefore, novel systems that provide efficient massive content delivery and reduced energy consumption are needed. In this paper, we present a network-coded cooperation (NCC) protocol for efficient massive content delivery and the analytical model that describes its behavior. The NCC protocol combines the benefits of cooperative architectures known as mobile clouds (MCs) with Random Linear Network Coding (RLNC). Our results show the benefits of our NCC protocol when compared to the establishment of numerous parallel unicast sessions are threefold: offload data traffic from the cellular link, reduce the energy consumption at the cooperating users, and provide throughput gains when the cellular bandwidth is insufficient.

Energy-Efficiency of Selective Relaying in a MIMO Network-Coded Cooperative System

We evaluate the outage probability and the energy efficiency (EE) of a network composed of multiple sources, multiple relays and a single common destination, all of them provided with multiple antennas. More specifically, we resort to the network-coded cooperative (NCC) technique with multiple relay selection (MRS) and compare the EE of the network when operating under two combining techniques at the receiver, namely selection combining (SC) and maximum ratio combining (MRC). Our analysis, which adopts a realistic energy consumption model that encompasses the circuitry consumption, shows that MRC, which is optimal from the reliability perspective, may be outperformed by SC in terms of EE. Moreover, we also provide some insights about the number of relays that must be selected to maximize the EE. Finally, numerical results are presented and confirm the mathematical analysis.

Implementation of Network-Coded Cooperation for Energy Efficient Content Distribution in 5G Mobile Small Cells

The continuous increase of mobile data traffic calls for the design of energy-efficient content distribution mechanisms, to be incorporated in the fifth generation of mobile networks, 5G. One of the biggest concerns of the companies and the research community is to reduce the energy consumption in both the user equipments (UEs) and the network equipment. In this article, we present a novel content distribution framework called Network-Coded Cooperative (NCC) Networks, which benefits from the interplay between mobile clouds (MC) and Random Linear Network Coding (RLNC) to reduce the overall energy consumption in the devices that take part in the communication. This novel framework leads to reduced energy consumption by offloading the cellular interface to a link with greater energy efficiency, for instance, WiFi, within the mobile small cell. We evaluate the performance of our framework analytically and in practical implementation (i.e., testbed) in terms of throughput, energy savings, packet decoding ratio, latency, and synchronicity. In comparison to the conventional content distribution system, for the case of four users, the analytical model and the testbed implementation show energy savings of more than 12% and 8%, respectively. Furthermore, network usage is reduced, losses are neutralized, and the content is synchronously distributed to all users.

Two-User Network-Coded Cooperation With NOMA and Advanced Successive Interference Cancellation

In this work, we evaluate the outage probability of a two-user network-coded cooperative (NCC) uplink system subjected to non-orthogonal multiple access (NOMA). We consider that the destination performs a recently proposed advanced successive interference cancellation (Adv-SIC) in order to decode the individual messages from the superimposed received signal, which requires only statistical channel state information (CSI). Our results indicate, through mathematical analysis and numerical simulations, that the benefits of Adv-SIC are boosted by NCC, improving the performance of both users, differently from a non-cooperative (NonCooP) NOMA system, where only the user with the worst average channel condition is benefited from Adv-SIC.

Relay Selection in Network-Coded Cooperative MIMO Systems

Network-coded cooperation (NCC) has recently gained interest as it improves the network throughput in multi-source cooperative systems. NCC has been studied for single-antenna terminals only. Employing multiple-input multiple-output (MIMO) techniques can significantly improve the performance of NCC systems. Furthermore, the existing relay selection (RS) strategies for NCC utilize the “max-min” end-to-end (E2E) criterion. This selection strategy (called Strategy $\mathcal {A}$ ) is complicated even for a network with single-antenna terminals as it requires global channel state information (CSI). This requirement makes it hard to implement RS-based NCC. To counter this issue, we introduce a new RS strategy (Strategy $\mathcal {B}$ ), which utilizes only the local CSI (not global CSI), significantly reducing the signaling overhead without sacrificing the performance. The performance of MIMO-NCC under Strategies $\mathcal {A}$ and $\mathcal {B}$ is studied over independent and non-identically distributed (i.n.i.d.) Rayleigh fading channels. Relays and the destination are equipped with multiple antennas, whereas sources have a single antenna. The exact outage probability expressions of the system under consideration are derived. The asymptotic outage expressions are further provided to obtain valuable insights into the practical system-design parameters such as the diversity order and coding gain. Furthermore, numerical results are provided in support of the analytical results.

Multiple relay‐based Reed–Muller network‐coded cooperation for wireless communication system

This research article proposes a multiple relay-based Reed–Muller network-coded cooperative (MR-RMNCC) scheme for wireless communication. In the MR-RMNCC scheme, Hadamard transform construction is adopted to build Reed–Muller (RM) codes that effectively achieve network coded-cooperation among multiple sources and multiple relays over slow and fast Rayleigh fading channels. In any network coded-cooperative system, a proper encoding strategy at the relay nodes is vital for achieving an optimum code construction at the destination node. Therefore, the authors have proposed an efficient message bit selection algorithm at relay-2 that optimally selects the message bits. The supremacy of the message bit selection algorithm is demonstrated by Monte–Carlo simulation. Furthermore, the performance bound for average error-probability is also derived for the MR-RMNCC scheme that validates its simulated bit-error-rate performance over a fast Rayleigh fading channel. At the destination node, the MR-RMNCC scheme is jointly decoded by two different decoding strategies, i.e. joint soft maximum likelihood decoding and joint majority logic decoding. Monte–Carlo simulations suggest that the MR-RMNCC scheme not only provides a significant bit-error-rate performance gain over its corresponding coded non-cooperative scheme but also to the existing state-of-the-art RM network-coded cooperative scheme under identical conditions.

Novel Cooperative MAC Aware Network Coding Under Log-Normal Shadowing Channel Model in Wireless Body Area Network

Cooperative communications exploit intermediate nodes in order to forward information and they have been used as a successful method in combating channel fading and enhancing network performance. Network coding combines several data packets to be sent, and it is very useful in minimizing network redundancy and improving the overall throughput and energy efficiency. Therefore, combining the cooperative communications and network coding allows the relay node to help other nodes while serving its own traffic concurrently. In this paper, a novel Two Master Nodes – Cooperative Network Coding (TMN-CNC) protocol is proposed, based on the IEEE 802.15.6 CSMA policy under log-normal shadowing channel model, for the wireless body area network (WBAN). The design objective of the TMN-CNC is to increase throughput and maximise energy efficiency. The numerical results show that the TMN-CNC can enhance network performance under general conditions compared to direct transmission IEEE 802.15.6 CSMA and incremental conventional cooperative communication (iCCC). In order to achieve this, it has been shown that the energy saving of the TMN-CNC is 60% compared to direct transmission IEEE 802.15.6 CSMA and 50% compared to iCCC.

Multiuser Diversity in Network-Coded Cooperation: Outage and Diversity Analysis

In this letter, we study multiuser diversity (MUD) in network-coded cooperation (NCC) systems. Specifically, we propose a two-step user-relay selection mechanism that selects subsets of users and relays to exploit both MUD and cooperative diversity in a multiuser multirelay NCC system. Assuming independent but not necessarily identically distributed Rayleigh fading channels, we derive closed-form expressions for the system outage probability. We further obtain asymptotic outage expressions to quantify the diversity order as a function of different system parameters. Our results demonstrate the superiority (diversity gains) of the proposed MUD-based NCC compared with NCC schemes without MUD. Monte-Carlo simulations are also presented to verify the accuracy of our theoretical findings.

LDPC based Network Coded Cooperation Design for Multi-way Relay Networks

In this paper, we focus on the reliable network coded cooperation design for multi-way relay network (MWRN) with m users and one single relay, in which every user is supposed to exchange data with all the other m - 1 users (full data exchange) by the assistance of the relay. By reformulating the multi-way relaying network in the framework of error control coding, the LDPC based network coded cooperation design issue for MWRNs is presented. On the basis, the requirements, design criteria, and practical design were proposed to demonstrate how to devise reliable network coded cooperation scheme, such that every user is capable of reliably exchanging data with the other m - 1 users. Our analysis shows that the proposed LDPC based network coded cooperation design exhibits powerful error correction capability, especially when compared with the existing schemes. And the overall required number of time slots to accomplish the proposed LDPC based network coded cooperation scheme is 2m.