Physical Layer Characteristics 1 Physical characteristics of mobile wireless networks
نویسنده
چکیده
As the name suggests, wireless systems operate by transmission through space rather than through wired connection. There are two major problems to be addressed in a wireless setting that do not arise in the wired case. The first is that the channel over which communication takes place is time varying. The second being interference between multiple users using a common communication medium. Therefore in wireless systems, we must combat not only noise but also time varying properties and interference. In general, wireless communication devices may be mobile (eg. cell phones, radio transceivers mounted on cars, aircrafts, etc) or stationary (eg. base stations of cellular networks).
منابع مشابه
Vehicular Networks: A Survey on Architecture, Communication Technologies and Applications
The Intelligent Transportation System (ITS) provides wireless and mobile communication between vehicles and infrastructure to improve the safety of transportation and make the journey more enjoyable. This system consists of many fixed and mobile nodes (Vehicles, Trains, Vessels, Air planes), Wireless and Wired Telecommunication Technologies to exchange information between mobile nodes or betwee...
متن کاملA Comparison between Different Meta-Heuristic Techniques in Power Allocation for Physical Layer Security
Node cooperation can protect wireless networks from eavesdropping by using the physical characteristics of wireless channels rather than cryptographic methods. Allocating the proper amount of power to cooperative nodes is a challenging task. In this paper, we use three cooperative nodes, one as relay to increase throughput at the destination and two friendly jammers to degrade eavesdropper&rsqu...
متن کاملRouting Hole Handling Techniques for Wireless Sensor Networks: A Review
A Wireless Sensor Network consists of several tiny devices which have the capability to sense and compute the environmental phenomenon. These sensor nodes are deployed in remote areas without any physical protections. A Wireless Sensor Network can have various types of anomalies due to some random deployment of nodes, obstruction and physical destructions. These anomalies can diminish the sensi...
متن کاملCross-Layer Radio Resource Allocation in Packet CDMA Wireless Mobile Networks with LMMSE Receivers
Most of previous study of radio resource allocation in traditional wireless networks concentrates on network layer connection blocking probability QoS. In this paper, we show that physical layer techniques and QoS have significant impact on network layer QoS. We define a novel concept of cross-layer effective bandwidth and use this to measure the unified radio resource usage taking into account...
متن کاملDynamic physical layers for wireless networks using software radio
The communication parameters in mobile ad-hoc networks, such as the distance between nodes, channel characteristics, and user demands can vary quickly. Using traditional design techniques and creating a static physical layer designed to meet worst case conditions will result in poor performance and resource utilization under most operating conditions. Software radios, which implement their phys...
متن کامل