Queueing Delay Analysis Research Articles

Broadcast Approach to Uplink NOMA: Queuing Delay Analysis

Broadcast Approach to Uplink NOMA: Queuing Delay Analysis

Broadcast Approach to Uplink NOMA: Queuing Delay Analysis.

Emerging wireless technologies are envisioned to support a variety of applications that require simultaneously maintaining low latency and high reliability. Non-orthogonal multiple access techniques constitute one candidate for grant-free transmission alleviating the signaling requirements for uplink transmissions. In open-loop transmissions over fading channels, in which the transmitters do not have access to the channel state information, the existing approaches are prone to facing frequent outage events. Such outage events lead to repeated re-transmissions of the duplicate information packets, penalizing the latency. This paper proposes a multi-access broadcast approach in which each user splits its information stream into several information layers, each adapted to one possible channel state. This approach facilitates preventing outage events and improves the overall transmission latency. Based on the proposed approach, the average queuing delay of each user is analyzed for different arrival processes at each transmitter. First, for deterministic arrivals, closed-form lower and upper bounds on the average delay are characterized analytically. Secondly, for Poisson arrivals, a closed-form expression for the average delay is delineated using the Pollaczek-Khinchin formula. Based on the established bounds, the proposed approach achieves less average delay than single-layer outage approaches. Under optimal power allocation among the encoded layers, numerical evaluations demonstrate that the proposed approach significantly minimizes average sum delays compared to traditional outage approaches, especially under high arrival rates.

Modeling Queuing Delay of 5G NR With NOMA Under SINR Outage Constraint

In this paper, we present an analytical model to characterize the average queuing delay for non-orthogonal multiple access (NOMA) downlink system by taking the outage event into account such that the user fails either decoding its own signal or performing SIC for the signals of other users at the receiver when the SINR is lower than a predefined outage threshold. The departure process of the queuing model is characterized by obtaining the first and second moment statistics of the service time that depends on the resource allocation strategy, the packet size and channel distributions. The proposed model is utilized to obtain the optimum power allocation that minimizes the maximum of the average queuing delay (MAQD) for a two-user network scenario. The Monte Carlo simulation experiments are performed to numerically validate the model by providing MAQD results for both NOMA and orthogonal multiple access (OMA) schemes. The results demonstrate that the NOMA achieves lower latency for low SINR outage thresholds while its performance is degraded faster than OMA as the SINR outage threshold increases such that OMA outperforms NOMA beyond a certain threshold. Another important result is that the latency performance of NOMA is significantly degraded when the 5G NR frame types having wider bandwidth are utilized. The results provide powerful insights for queuing delay analysis of 5G services.

RETRACTED: The effect of commodity promotion strategy based on psychological distance theory on consumer's purchase behavior intention

In order to enhance effective analysis on the consumers’ purchasing intention, this paper puts forward an analysis method for the influence of commodity promotion strategy based on game balance decision on customers’ purchasing intention. Firstly, according to the intervention degree of consumers in purchasing process and difference between brands, it classifies the consumers’ purchasing behavior, and establishes model analysis methods for different types. Secondly, it puts forward a game balance queuing delay analysis strategy in order to enhance dispatching efficiency, and conducts iterative adjustment on queuing delay analysis strategy by aid of game balance solution; finally, it verifies the performance and advantage of the mentioned method through simulation study, thus presenting the algorithm effectiveness.

Queueing Delay Analysis and Optimization of Statistical Data Aggregation and Transmission Systems

Queueing Delay Analysis and Optimization of Statistical Data Aggregation and Transmission Systems

Deterministic Quality of Service Guarantee for Dynamic Service Chaining in Software Defined Networking

In this paper, we present a systemic approach to provide deterministic delay guarantee for dynamic service chaining in software defined networking (SDN). The delay performance of service chaining in SDN is affected by signaling message exchange in control plane and packet transmissions in data plane, respectively. First, we develop an analytical method to characterize the delay performance of control plane when handling traffic with different priorities according to network calculus (NC) and queuing theory. Second, taking into account the estimated delay in control plane, we propose a novel service traversal mechanism to calculate the optimal traversal path for the service chain. We demonstrate that NC delay analysis can provide deterministic quality of service (QoS)-guaranteed service chaining for any specified delay requirements, whereas theoretical queueing delay analysis can only provide statistical QoS guarantee. In summary, the proposed NC delay analysis can help to understand the network design for a future delay sensitive Internet in which deterministic latency must be guaranteed.

The queuing delay analysis at relay node based on cooperative GBN-ARQ protocols

In this paper, a single relay cooperative diversity network model is proposed, analyzing queuing delay of the packets at relay node. Using dynamic radio link adaptation in wireless networks, based on the character of GBN-ARQ protocol and the queuing theory, the paper solves the problem that packets wait to transmit at relay, and presents a relay node to destination node queuing analysis model for GBN-ARQ protocol with fixed feedback delay. The paper establishes Markov model of packet transmission, and the delay statistics at relay node are figured out by using matrix geometric methods.

Optimal Pricing for Duopoly in Cognitive Radio Networks: Cooperate or not Cooperate?

Pricing is an effective approach for spectrum access control in cognitive radio (CR) networks. In this paper, we study the pricing effect on the equilibrium behaviors of selfish secondary users' (SUs') data packets which are served by a CR base station (BS). From the SUs' point of view, a spectrum access decision on whether to join the queue of the BS or not is characterized through an individual optimal strategy that is joining the queue with a joining probability. This strategy also requires each SU to know the average queueing delay, which is a non-trivial problem. Toward this end, we provide queueing delay analysis by using the M/G/1 queue with breakdown. From the BS's point of view, we consider a duopoly market based on the two paradigms: the opportunistic dynamic spectrum access (O-DSA) and the mixed O-DSA & dedicated dynamic spectrum access (D-DSA). In the first paradigm, two co-located opportunistic-spectrum BSs utilize freely spectrum-holes to serve SUs. Then, we show the advantages of the cooperative scenario due to the unique solution that can be obtained in a distributed manner by using the dual decomposition algorithms. For the second paradigm, there are one opportunistic-spectrum BS and one dedicated-spectrum BS. We study a price competition between two BSs as a Stackelberg game. The cooperative behavior between two BSs is modeled as a bargaining game. In both paradigms, bargain revenues of the cooperation are always higher than those due to competition in both cases. Extensive numerical analysis is used to validate our derivation.

Optimal Pricing Effect on Equilibrium Behaviors of Delay-Sensitive Users in Cognitive Radio Networks

This paper studies price-based spectrum access control in cognitive radio networks, which characterizes network operators' service provisions to delay-sensitive secondary users (SUs) via pricing strategies. Based on the two paradigms of shared-use and exclusive-use dynamic spectrum access (DSA), we examine three network scenarios corresponding to three types of secondary markets. In the first monopoly market with one operator using opportunistic shared-use DSA, we study the operator's pricing effect on the equilibrium behaviors of self-optimizing SUs in a queueing system. We provide a queueing delay analysis with the general distributions of the SU service time and PU traffic using the renewal theory. In terms of SUs, we show that there exists a unique Nash equilibrium in a non-cooperative game where SUs are players employing individual optimal strategies. We also provide a sufficient condition and iteraIntive algorithms for equilibrium convergence. In terms of operators, two pricing mechanisms are proposed with different goals: revenue maximization and social welfare maximization. In the second monopoly market, an operator exploiting exclusive-use DSA has many channels that will be allocated separately to each entering SU. We also analyze the pricing effect on the equilibrium behaviors of the SUs and the revenue-optimal and socially-optimal pricing strategies of the operator in this market. In the third duopoly market, we study a price competition between two operators employing shared-use and exclusive-use DSA, respectively, as a two-stage Stackelberg game. Using a backward induction method, we show that there exists a unique equilibrium for this game and investigate the equilibrium convergence.

Queueing Delay Analysis for Multicast With Random Linear Coding

We analyze the queueing delay performance when random linear coding is performed over packets randomly arriving at a source node for multicast transmission over packet erasure channels. We model random coding of packets as a bulk-service queueing system, where packets are served and depart the queue in groups. In this framework, we analyze two different block-based random linear coding schemes. The first scheme involves coding over a fixed blocksize, which leads to simpler analysis but also to a delay penalty for lightly-loaded systems. The second scheme adapts to the traffic load by allowing for a variable blocksize, thereby removing the delay penalty at low loads. We provide results on the maximum stable arrival rate of packets at the source and on the queueing delay as a function of the arrival rate.

ALOHA With Collision Resolution (ALOHA-CR): Theory and Software Defined Radio Implementation

A new scheme, namely ALOHA with Collision Resolution (ALOHA-CR) is proposed, which is a cross-layer approach for high throughput wireless communications in a cellular uplink scenario. Transmissions occur in a time-slotted ALOHA-type fashion but with an important difference: simultaneous transmissions of two users can be successful. In the beginning of each slot, users with non-empty queues contend with some probability after experiencing an intentional random delay. If more than two users transmit in the same slot, no attempt is made by the base station (BS) to separate the collision; the packets are discarded and the users are asked to retransmit at a later time. If one or two users transmit, then, depending on the state of the channel, the base station can recover the transmitted packets. The latter is achieved by oversampling the collision signal and exploiting independent information about the users that is contained in the signal polyphase components. The properties of the user intentional random delays are determined to maximize the probability of a second order collision being separable. The throughput of ALOHA-CR under both infinite and finite backlog assumptions is derived. Under the former assumption, the optimal contention probability is calculated to maximize the system throughput, while under the latter assumption, the region of stabilizing contention probabilities is determined based on the packet arrival rate. Queuing delay analysis for network users is also conducted. The performance of ALOHA-CR is demonstrated on the Wireless Open Access Research Platform (WARP) testbed containing five software defined radio nodes. The testbed results indicate that ALOHA-CR leads to significant increase in throughput and reduction of service delays as compared to ALOHA.

Queueing Delay Analysis for the Joint Scheduling Exploiting Multiuser Diversity over a Fading Channel

In this paper, we consider a joint packet scheduling algorithm for wireless networks and investigate its characteristics. The joint scheduling algorithm is a combination of the Knopp and Humblet (KH) scheduling, which fully exploits multiuser diversity, and the probabilistic weighted round-robin (WRR) scheduling, which does not use multiuser diversity at all. Under the assumption that the wireless channel process for each user is described by the Nakagami-m model, we develop a formula to estimate the tail distribution of the packet delay for an arbitrary user under the joint scheduling. Numerical results exhibit that under the joint scheduling, the ratio of the number of slots assigned for the WRR scheduling to that for the KH scheduling dominates the characteristics of the delay performance.

Schedulability-driven frame packing for multicluster distributed embedded systems

We present an approach to frame packing for multicluster distributed embedded systems consisting of time-triggered and event-triggered clusters, interconnected via gateways. In our approach, the application messages are packed into frames such that the application is schedulable, thus the end-to-end message communication constraints are satisfied. We have proposed a schedulability analysis for applications consisting of mixed event-triggered and time-triggered processes and messages, and a worst-case queuing delay analysis for the gateways, responsible for routing inter-cluster traffic. Optimization heuristics for frame packing aiming at producing a schedulable system have been proposed. Extensive experiments and a real-life example show the efficiency of our frame-packing approach.

Expected time in system analysis of a single-machine multi-item processing center

Traditionally, cost models are studied to support decision making for production planning. However, criticism of cost accounting methods led to a growing interest in physical measures of manufacturing performance. Time based competition is one of the concepts that supports the use of these physical measures such as manufacturing lead time. Next to factors as finite capacity and priority rules the batching decision is one of the determinants of lead time. Time in system analysis to find analytical expressions for the optimal batching decision is a complex task. For that reason one has to rely on approximating approaches. In this paper two approaches will be compared. At high utilization levels, queueing delays build up the larger part of total lead time and for that reason, a lot of authors study the relationship between queueing delays and lot sizes. However, especially for low levels of utilization queueing delay analysis won’t suffice. For that reason a second effective analytical approximation of the minimal time in system and the accompanying batch sizes is derived. This approximation is based on the insensitivity of the optimal solution to the total fraction of time spent on executing setups (setup utilization).

Schedulability-driven frame packing for multi-cluster distributed embedded systems

We present an approach to frame packing for multi-cluster distributed embedded systems consisting of time-triggered and event-triggered clusters, interconnected via gateways. In our approach, the application messages are packed into frames such that the application is schedulable. Thus, we have also proposed a schedulability analysis for applications consisting of mixed event-triggered and time-triggered processes and messages, and a worst case queuing delay analysis for the gateways, responsible for routing inter-cluster traffic. Optimization heuristics for frame packing aiming at producing a schedulable system have been proposed. Extensive experiments and a real-life example show the efficiency of our frame-packing approach.

Schedulability analysis and optimisation for the synthesis of multi-cluster distributed embedded systems

An approach to schedulability analysis for the synthesis of multi-cluster distributed embedded systems consisting of time-triggered and event-triggered clusters, interconnected via gateways, is presented. A buffer size and worst case queuing delay analysis for the gateways, responsible for routing inter-cluster traffic, is also proposed. Optimisation heuristics for the priority assignment and synthesis of bus access parameters aimed at producing a schedulable system with minimal buffer needs have been proposed. Extensive experiments and a real-life example show the efficiency of the approaches.