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.
The evolved packet system is being standardized and developed to provide IP-based mobile data services as well as traditional voice service. As voice service is still deemed one of the key EPS services, mobile operators have to make sure subscribers enjoy the same quality of user experience for voice service while new IP-based data services become available. In this article we review the three solutions,...
A mobile ad hoc network (MANET) consists of mobile nodes that communicate with each other without any infrastructure. MANET has various applications including military operations, rescue operations, and many other situations that require rapidly deployable communication networks. In order to evaluate the performance of such networks accurately through simulations, we need to use realistic conditions...
Carrier sense multiple access (CSMA) is a media access scheme used in multi-hop wireless networks. Because a node is unable to detect a collision while it transmits signals, reducing the collision rate is important to increase the network performance. Since the advent of MACA, it has been believed that RTS/CTS exchange in multi-hop wireless networks prevents collisions caused by hidden terminals in...
IEEE 802.11 DCF mode is a distributed channel access method for standard Wireless Local Area Networks (WLAN) with a goal of providing long-term fair channel access for the nodes. Due to the characteristics of radio signals, such as propagation attenuation and capture effect, WLAN users may experience unfair medium allocations depending on their locations. Our analysis shows that a user near the access...
Cognitive radio (CR) offers a new mechanism for flexible usage of radio spectrum. This paper presents a full-duplex multi-channel MAC protocol designed for CR enabled multi-hop networks. Each node is equipped with at least two transceivers, one for transmitting and another for receiving. A node selects an unused frequency band as its home channel (HCh) and tunes its receiver to its HCh. When a node...
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.