The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Packet loss in 802.11 WLANs (wireless local area networks) can occur either because of collision or a signal that is not strong enough at the receiver antenna. A challenging issue is the determination of packet loss cause once it occurs, which is a key for improving the performance of 802.11 WLANs. This article proposes and evaluates an algorithm to achieve this goal. The core of this algorithm is...
In Wireless Local Area Networks (WLANs), the estimation of interference conditions at a receiving node and the determination of interference relations among different wireless nodes is a challenging problem. Interference relations provide the information of which wireless links do interfere if activated concurrently. This information is crucial for the determination of which wireless links are allowed...
This paper proposes a framework for interference mitigation in multi-BSS infrastructure 802.11 WLANs. Our interference mitigation approach is based on access point (AP) coordination. With this approach, interfering BSSs negotiate and switch from the 802.11 CSMA/CA to a time slotted mechanism if users' QoS is observed to be degraded, diagnoses conclude that the cause is high interference, and the switch...
This paper proposes a new decentralized Access Point Selection Policy for 802.11 Wireless Local Area Networks (WLANs). We derive a decision metric towards AP selection improvement. The derived metric comprises both Inter-BSS and Intra-BSS interference. Our proposed policy is decentralized in the sense that the decision is performed by each station. The core of the policy is based on measurement reports...
Despite the fact that the Request-To-Send/Clear-To-Send (RTS/CTS) protocol significantly reduces collisions and retransmissions due to the hidden node problem, it is well known that it adds considerable overhead specially with small payload packets. The IEEE 802.11 standard defined a manageable parameter, RTS threshold, above which a data packet should be preceded with RTS/CTS handshake. In this paper,...
In this paper we address the problem of distance measurement in indoor IEEE 802.11 WLANs. The Received Signal Strength Indicator (RSSI) and the Signal Propagation Time (SPT) have been widely used for distance estimation in indoor WLAN deployments. However, neither approach by itself is accurate. Moreover, there is no mean by which WLAN nodes know whether the estimated distance is accurate or not....
One of the key challenges of the emerging cognitive radio-based IEEE 802.22 wireless regional area networks (WRANs) is to address two apparently conflicting requirements: ensuring QoS satisfaction for WRAN services while providing reliable spectrum sensing for guaranteeing licensed user protection. To perform reliable sensing, in the basic operation mode on a single frequency band (non-hopping mode),...
In wireless local area networks often a station can potentially associate with more than one access point. Therefore, a relevant question is which access point to select "best" from a list of candidate ones. In IEEE 802.11, the user simply associates to the access point with the strongest received signal strength. However, this may result in a significant load imbalance between several access...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.