In this paper, we propose a novel MAC scheme that dynamically optimizes each active node's backoff process. Through theoretical analysis, we find that the average channel idle interval can represent current network traffic load and then can used together with estimated number of nodes for setting optimal . Since necessary indexes can be obtained through direct measurement, our scheme will not increase any added load to networks, which makes our schemes simpler and more reliable when network traffic reaches saturated. Through simulation comparison with previous schemes, we show that our scheme can greatly improve the throughput no matter the network is in saturated or non-saturated case, while maintaining good fairness.

SUMMARYWLANs have become increasingly popular and widely deployed. The MAC protocol is one of the important technology of the WLAN and affects communication efficiency directly. In this paper, focusing on MAC protocol, we propose a novel protocol that network nodes dynamically optimize their backoff process to achieve high throughput while supporting satisfied QoS. A distributed MAC protocol has an advantage that no infrastructure such as access point is necessary. On the other hand, total throughput decreases heavily and cannot guarantee QoS under high traffic load, which needs to be improved. Through theoretical analysis, we find that the average idle interval can represent current network traffic load and can be used together with estimated number of nodes for setting optimal CW. Since necessary indexes can be obtained directly through observing channel, our scheme based on those indexes will not increase any added load to networks, which makes our schemes simpler and more effective. Through simulation comparison with conventional method, we show that our scheme can greatly enhance the throughput and the QoS no matter the network is in saturated or non-saturated case, while maintaining good fairness.

Abstract-WLANs have become increasingly popular and widely deployed. The MAC protocol is one of the important technology of the WLAN and affects communication efficiency directly. In this paper, focusing on MAC protocol, we propose a novel protocol that network nodes dynamically optimize their backoff process to achieve high throughput while supporting satisfied QoS. The total throughput decreases heavily and cannot guarantee QoS under a high traffic load, which needs to be improved. Through theoretical analysis, we find that the average idle interval can represent current network traffic load and can be used together with estimated number of nodes for setting optimal CW. Since necessary indexes can be obtained through direct measurement from channel, our scheme will not increase any added load to networks. Through simulation comparison with conventional method, we show that our scheme can greatly enhance the throughput and the QoS no matter the network is in saturated or non-saturated case, while maintaining good fairness.

WLANs have become increasingly popular and widely deployed. The MAC protocol is one of the important technologies of the WLANs and affects communication efficiency directly. A distributed MAC protocol has the advantage that infrastructure such as an access point is unnecessary. On the other hand, total throughput decreases heavily increase in network density, which needs to be improved. Previous research works gave proposals with improved throughput but a degraded fairness. In this paper, focusing on MAC protocol, we propose a novel protocol that each node estimates the number of nodes in a network with a short convergence time and no overhead traffic burden added to the network through observing the channel, and nodes dynamically optimize their backoff process to achieve high throughput and satisfactory fairness. Since necessary indexes can be obtained through direct measurement from the channel, our scheme will not involve any added load to networks, which makes our schemes simpler and more effective. Through simulation comparison with recently proposed methods, we show that our scheme can greatly enhance the throughput with good fairness without it signifying whether the network is in saturated or non-saturated state.