Multi-packet Transmission Research Articles

Dissipativity-based control for networked control systems under bilateral Round-Robin protocols and denial-of-service attacks

A dissipativity-based control strategy adopting bilateral Round-Robin (RR) protocols for networked control systems (NCSs) suffering from denial-of-service (DoS) attacks is investigated in this work. To save limited network resources in multi-packet transmission scenarios, RR protocols are adopted for coordinating the node access on bilateral (i.e., sensor-to-controller and controller-to-actuator) channels. Subsequently, the NCSs integrating considerations of bilateral RR protocols and DoS attacks are further described as the switched time-delay model. The sufficient stability condition and controller design criterion are derived by using Lyapunov theory to ensure the closed-loop exponential mean-square stability and (Q,S,R) dissipative performance under fragile network environment. Furthermore, to maximize the tolerable system delay and reduce the conservativeness of proposed results effectively, an optimization algorithm is also proposed. Finally, the superiority and feasibility of the proposed methods are verified through two practical examples.

Attack-model-independent stabilization of networked control systems under a jump-like TOD scheduling protocol

This paper is concerned with the stabilization of networked control systems (NCSs) under multi-packet transmission and denial of service (DoS) attacks. To deal with node congestions and DoS attacks, a jump-like try-once-discard (TOD) protocol is first proposed to orchestrate the priority of normal nodes and the attacked nodes over the network. Compared with the existing TOD scheduling, the proposed scheduling scheme has the advantage of jumping out the attacked nodes by designing node weighting matrices. To reduce the effects of DoS attacks, an attack-model-independent impulsive closed-loop model is well established, which couples the effects of the proposed protocol and DoS attacks in a unified framework. Then, a sufficient attack-model-independent stabilization criterion is derived. Compared with the existing attack-model-dependent methods, the desired dynamic output feedback performance is well guaranteed under multi-channel time-varying DoS attacks. Finally, an illustrative example is used to verify the effectiveness of proposed method.

Networked scheduling for decentralized load frequency control

This paper investigates the scheduling process for multi-area interconnected power systems under shared but band-limited networks and decentralized load frequency controllers. To cope with sub-area information and avoid node collision of large-scale power systems, round-robin and try-once-discard scheduling are used to schedule sampling data among different sub-grids. Different from existing decentralized load frequency control methods, this paper studies multi-packet transmission scheme and introduces scheduling protocols to deal with multi-node collision. Considering the scheduling process and decentralized load frequency controllers, an impulsive power system closed-loop model is well established. Furthermore, sufficient stabilization criteria are derived to obtain decentralized output feedback controller gains and scheduling protocol parameters. Under the designed decentralized output feedback controllers, the prescribed system performances have been achieved. Finally, a three-area power system example is used to verify the effectiveness of the proposed scheduling method.

Multi-packet transmission aero-engine DCS neural network sliding mode control based on multi-kernel LS-SVM packet dropout online compensation.

In view of the strong nonlinear characteristics of the multi-packet transmission Aero-engine DCS with induced delay and random packet dropout, a neural network PID approach law sliding-mode controller using sliding window strategy and multi-kernel LS-SVM packet dropout online compensation is proposed. Firstly, the time-delay term in the system model is transformed equivalently, to establish the discrete system model of multi-packet transmission without time-delay; furthermore, the construction of multi-kernel function is transformed into kernel function coefficient optimization, and the optimization problem can be solved by the chaos adaptive artificial fish swarm algorithm, then the online predictive compensation will be made for data packet dropout of multi-packet transmission through the sliding window multi-kernel LS-SVM. After that, a sliding-mode controller design method of proportional integral differential approach law based on neural network is proposed. And online adjustment of PID approach law parameters can be achieved by nonlinear mapping of neural network. Finally, Truetime is used to simulate the method. The results shows that when the packet dropout rate is 30% and 60%, the average error of packet dropout prediction of multi-kernel LS-SVM reduces 29.21% and 44.66% compared with that of combined kernel LS-SVM, and the chattering amplitude of the proposed neural network PID approach law sliding-mode controller is decreased compared with other five approach law methods respectively. This controller can ensure a fast response speed, which shows that this method can achieve a better tracking control of the aeroengine network control system.

Stability Analysis of Networked Control Systems with Multi-Packet Dropout based on Switched System Approach

Networked control system models with packet dropout in multi-packet transmission were established under hypothetical conditions in this paper, and the system was seen as a switched system. The causes of packet dropout in networked control system are analyzed in view of single-packet transmission and multi-packet transmission respectively. Based on Lyapunov stability theory, the property of the networked control system with multi-packet dropout was analyzed from the point of view of an asynchronous dynamic system. The method which determined the multi-packet dropout boundary to keep the system steady was given. The simulation results show the influences of multi-packet dropout on the system performance and prove the validity of the analytical method proposed in this paper.

Design and Analysis of Optimization based Integrated ANFIS- PID Controller for Networked Controlled Systems (NCSs).

Frequent occurrence of control loops in network systems leads to various issues such as packet loss, random delays, multi-packet transmission etc. Actually, in networked control systems, random delays present more significant and challenging issue. In order to enhance the performance of the network, various soft computing techniques were presented in previous works for both scenarios i.e. with delay and without delay, in which Fuzzy-PID controllers were regarded as the most efficient one. However, it is analyzed that Fuzzy-PID approach lacks in some aspects that leads to inefficient system performance. Therefore, in this paper, a novel and more efficient approach is introduced, i.e. ANFIS-PID controller. Also, this presented ANFIS-PID controller is a modified version of traditional ANFIS approach and it is optimized by using Grey Wolf Optimization (GWO) algorithm. The simulation of the proposed approach is processed for both with and without time delay consideration to perform analysis over Peak Overshoot, Settling Time and Rise Time of the network. The outcomes represent that the proposed model is quite efficient and successful to achieve the system output with lesser transmission delays and packet dropouts along with the enhanced accuracy level in comparison to the traditional system.

Corrections to “Efficient Design of Multi-Packet Hybrid ARQ Transmission Scheme Based on Polar Code”

In the above article [1] , we did not pay enough attention to distinguishing the contributions between our work and article [2] clearly. Potential deficiencies in article writing may cause controversy or confusion to readers. We would like to provide some detailed comments.

Classification‐Based Control for Wireless Networked Control Systems with Lossy Multipacket Transmission

A classification‐based control approach is proposed for wireless networked control systems with lossy multipacket transmission. This approach takes advantage of a state reconstruction process to deal with the distinct feature of partial failure of data transmission caused by multipacket transmission, and then classifies the difference of the latest received system states and reconstructed ones to design a classification‐based controller. The closed‐loop stability of the system is proven using the switched systems theory. By considering more communication characteristics of multipacket transmission, the proposed approach is shown to give rise to a better system performance by a numerical example. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Stochastic stabilisation of wireless networked control systems with lossy multi‐packet transmission

The stochastic stabilisation of networked control systems is investigated with a special focus on the lossy multi-packet transmission in the wireless communication context. The resulting partially available system states due to multi-packet transmission are firstly reconstructed at the controller, and the sufficient conditions for stochastic stability are then given for the closed-loop system, which finally leads to a controller design method with explicit consideration of multi-packet transmission. The proposed theoretical results are verified by both numerical and TrueTime-based examples.

Error-detection-coding-aided iterative hard decision interference cancellation for MIMO systems with HARQ

In this paper, an error-detection-coding-aided iterative hard decision interference cancellation (EDC-IHIC) scheme for multiple-input multiple-output systems employing hybrid automatic repeat request (HARQ) for multi-packet transmission is developed and investigated. In the EDC-IHIC scheme, only packets identified as error-free by the EDC are submitted to the interference cancellation (IC) stage for cancellation from the received signals. Therefore, the possibility of error propagation, including inter-transmission error propagation, can be eliminated using EDC-IHIC. Because EDC must be implemented in systems that employ HARQ to determine packet retransmission, error propagation can be prevented without the need for additional redundancy. The results of simulations conducted herein verify that the EDC-IHIC scheme outperforms conventional hard decision IC schemes in terms of the packet error rate in various environments.

Fault detection in finite frequency domain for constrained networked systems under multi-packet transmission

In this paper, the fault detection problem is studied in finite frequency domain for constrained networked systems under multi-packet transmission. The considered transmission mechanism is that only one packet including parts of the measured information can be transmitted through the communication channel and their accessing is scheduled by a designed stochastic protocol. Then by virtues of the introduced performance indices in finite frequency domain, a novel effective fault detection scheme is presented, in which the fault detection filters completing the task with partially available measurements are designed to make sure that the residual is sensitive to the reference input and the fault in faulty cases and robust to the reference input in fault-free case. Further, convex conditions in terms of time-domain inequalities are developed to handle the proposed fault detection scheme. The theoretical results are validated by the simulation to detect the sensor fault on a lateral-directional aerodynamic model.

MPT-MAC: Multi-Packet Transmission MAC Protocol in UWASNs

MPT-MAC: Multi-Packet Transmission MAC Protocol in UWASNs

Energy-Aware Cooperative Wireless Networks With Multiple Cognitive Users

In this paper, we study and analyze cooperative cognitive radio networks with arbitrary number of secondary users (SUs). Each SU is considered a prospective relay for the primary user (PU) besides having its own data transmission demand. We consider a multi-packet transmission framework that allows multiple SUs to transmit simultaneously because of dirty-paper coding. We propose power allocation and scheduling policies that optimize the throughput for both PU and SU with minimum energy expenditure. The performance of the system is evaluated in terms of throughput and delay under different opportunistic relay selection policies. Toward this objective, we present a mathematical framework for deriving stability conditions for all queues in the system. Consequently, the throughput of both primary and secondary links is quantified. Furthermore, a moment generating function approach is employed to derive a closed-form expression for the average delay encountered by the PU packets. Results reveal that we achieve better performance in terms of throughput and delay at lower energy cost as compared with equal power allocation schemes proposed earlier in the literature. Extensive simulations are conducted to validate our theoretical findings.

Performance analysis of a Multiuser Multi-Packet Transmission system for WLANs in non-saturation conditions

Multiuser Multi-Packet Transmission (MPT) from an Access Point (AP) equipped with multiple antennas to multiple single-antenna nodes can be achieved by exploiting the spatial dimension of the channel. In this paper we present a queueing model to analytically study such systems from the link-layer perspective, in presence of random packet arrivals, heterogeneous channel conditions and packet errors. The analysis relies on a blind estimation of the number of different destinations among the packets waiting in the queue, which allows for building a simple, but general model for MPT systems with per-node First-In First-Out (FIFO) packet scheduling. Simulation results validate the accuracy of the analytical model and provide further insights on the cross-relations between the channel state, the number of antennas, and the number of active users, as well as how they affect the system performance. The simplicity and accuracy of the model makes it suitable for the evaluation of Medium Access Control (MAC) protocols for Ad Hoc or Wireless Local Area Networks supporting Multiuser MPT in non-saturation conditions, where the queueing dynamics play an important role on the achieved performance, and simple user selection algorithms are required.

Multi-Packet Opportunistic Large Array Transmission on Strip-Shaped Cooperative Routes or Networks

The Opportunistic Large Array (OLA) is one type of cooperative transmission, which provides fast and reliable broadcasts and unicasts in multi-hop networks. While the existing literature on OLAs assumes one-shot transmission with a single packet, we analyze multi-packet OLA transmission within a single flow along strip-shaped networks or OLA-based cooperative routes. When multiple packets are transmitted from the same source using the same channel before the previous packet has cleared the network, which is called spatial pipelining, intra-flow interference is produced by OLAs transmitting co-channel packets. Using the continuum assumption (approximated by high density networks), the authors optimize the throughput. This paper theoretically shows spatial pipelining over strip networks is always feasible for path loss exponent α≥2, which is not true for disk-shaped networks. Moreover, the impacts of system parameters are analyzed, and the upper bound of the optimal packet spacing (the lower bound of the optimal throughput) is derived. Also, spatial pipelining in finite networks is studied with numerical results, which confirm the theoretical analysis.

Reliable Fault Detection for Nonlinear Networked Systems with Imperfect Measurements: A Multi-Packet Transmission Mechanism

In this paper, the reliable fault detection problem is investigated for a class of nonlinear networked systems with imperfect measurements. A novel measurement model is proposed to take the network-induced delays, random packet dropouts and sensor failures into consideration simultaneously. Different from commonly used single-packet transmission pattern, a multi-packet transmission mechanism is adopted in the sensor-to-filter channel, which allows the measured outputs being encapsulated into multiple packets and transmitted to the remote fault detection filter via different communication channels. In these channels, the network status may be quite different from each other. We aim to design a reliable fault detection filter such that, for all admissible unknown inputs and imperfect measurements, the error between the residual and the fault is kept as small as possible. By constructing an appropriate Lyapunov–Krasovskii functional, a sufficient condition for the existence of the desired reliable fault detection filter is established in terms of linear matrix inequalities, and the corresponding optimal filter parameters can be obtained by solving a convex optimization problem. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed method.

Performance analysis of CSMA/CA protocols with multi-packet transmission

Wireless objects equipped with multiple antennas are able to simultaneously transmit multiple packets by exploiting the channel’s spatial dimensions. In this paper, we study the benefits of such Multiple Packet Transmission (MPT) approach, when it is used in combination with a Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) protocol for fully interconnected networks, addressing the interactions between the two mechanisms and showing the performance gains that can be achieved. To this end, a very simple Media Access Control (MAC) protocol that captures the fundamental properties and tradeoffs of a CSMA/CA channel access protocol supporting MPT is introduced. Using this protocol as a reference, a new analytical model is presented for the case of non-saturated traffic sources with finite buffer space. Simulation results show that the analytical model is able to accurately characterize the steady-state behavior of the reference protocol for different number of antennas and different traffic loads, providing a useful tool for understanding the performance gains achieved by MAC protocols supporting MPT.

Modeling of Random Delays in Networked Control Systems

In networked control systems (NCSs), the presence of communication networks in control loops causes many imperfections such as random delays, packet losses, multipacket transmission, and packet disordering. In fact, random delays are usually the most important problems and challenges in NCSs because, to some extent, other problems are often caused by random delays. In order to compensate for random delays which may lead to performance degradation and instability of NCSs, it is necessary to establish the mathematical model of random delays before compensation. In this paper, four major delay models are surveyed including constant delay model, mutually independent stochastic delay model, Markov chain model, and hidden Markov model. In each delay model, some promising compensation methods of delays are also addressed.

Mitigating the effect of jamming signals in wireless ad hoc and sensor networks

In an infrastructure-less wireless ad hoc or sensor network, communication may be achieved between mobile nodes without a central entity (base station) using a half-duplex Slotted ALOHA protocol. The probability of success and the throughput per mobile node can be reduced significantly, if the network is attacked by jamming signals. Mitigating the effect of jamming signals using multi-packet transmission (MPT) and/or multi-packet reception (MPR) capabilities of each mobile node is studied. The effect of the probability of success reduction due to jamming signals can be mitigated by using the MPT and the MPR capabilities of each mobile node. Similarly, reduced throughput can be increased using the same techniques. The maximum throughput per mobile node can be obtained by the proper adjustment of the transmitting probability of each mobile node and the receiving probability of each mobile node. A lower mitigation of the maximum throughput reduction can be obtained by using only the MPT, if the jamming signal rate is very low. On the other hand, only the MPR capability can provide a lower mitigation of the maximum throughput reduction. The effect of jamming signals on the maximum throughput can be mitigated successfully at all traffic load conditions, if the MPT and the MPR capabilities work together.

On the multicast capacity of wireless ad hoc networks with network coding

In this paper, we study the contribution of network coding (NC) in improving the multicast capacity of random wireless ad hoc networks when nodes are endowed with multi-packet transmission (MPT) and multi-packet reception (MPR) capabilities. We show that a per session throughput capacity of Θ(nT3 (n)) can be achieved as a tight bound when each session contains a constant number of sinks where n is the total number of nodes and T(n) is the transmission range1. Surprisingly, an identical order capacity can be achieved when nodes have only MPR and MPT capabilities. This result proves that NC does not contribute to the order capacity of multicast traffic in wireless ad hoc networks when MPR and MPT are used in the network. The result is in sharp contrast to the general belief (conjecture) that NC improves the order capacity of multicast. Furthermore, if the communication range is selected to guarantee the connectivity in the network, i.e., Ω (√(log n/n)) = T(n) = O(log log n/log n), then the combination of MPR and MPT achieves a throughput capacity of Θ(log 3/2 n/√n) which provides an order capacity gain of Θ(log2 n) compared to the point- to-point multicast capacity with the same number of destinations.