Base station

About: Base station is a research topic. Over the lifetime, 85883 publications have been published within this topic receiving 1019303 citations. The topic is also known as: Mobile phone base stations & BS.

Energy-Aware Clustering for Wireless Sensor Networks using Particle Swarm Optimization

Abstract: Wireless sensor networks (WSNs) are mainly characterized by their limited and non-replenishable energy supply. Hence, the need for energy efficient infrastructure is becoming increasingly more important since it impacts upon the network operational lifetime. Sensor node clustering is one of the techniques that can expand the lifespan of the whole network through data aggregation at the cluster head. In this paper, we present an energy-aware clustering for wireless sensor networks using particle swarm optimization (PSO) algorithm which is implemented at the base station. We define a new cost function, with the objective of simultaneously minimizing the intra-cluster distance and optimizing the energy consumption of the network. The performance of our protocol is compared with the well known cluster-based protocol developed for WSNs, LEACH (low-energy adaptive clustering hierarchy) and LEACH-C, the later being an improved version of LEACH. Simulation results demonstrate that our proposed protocol can achieve better network lifetime and data delivery at the base station over its comparatives.

Vertical Handoff Decision Algorithms for Providing Optimized Performance in Heterogeneous Wireless Networks

Abstract: There are currently a large variety of wireless access networks, including the emerging vehicular ad hoc networks (VANETs). A large variety of applications utilizing these networks will demand features such as real-time, high-availability, and even instantaneous high-bandwidth in some cases. Therefore, it is imperative for network service providers to make the best possible use of the combined resources of available heterogeneous networks (wireless area networks (WLANs), Universal Mobile Telecommunications Systems, VANETs, Worldwide Interoperability for Microwave Access (WiMAX), etc.) for connection support. When connections need to migrate between heterogeneous networks for performance and high-availability reasons, seamless vertical handoff (VHO) is a necessary first step. In the near future, vehicular and other mobile applications will be expected to have seamless VHO between heterogeneous access networks. With regard to VHO performance, there is a critical need to develop algorithms for connection management and optimal resource allocation for seamless mobility. In this paper, we develop a VHO decision algorithm that enables a wireless access network to not only balance the overall load among all attachment points (e.g., base stations and access points) but also maximize the collective battery lifetime of mobile nodes (MNs). In addition, when ad hoc mode is applied to 3/4G wireless data networks, VANETs, and IEEE 802.11 WLANs for a more seamless integration of heterogeneous wireless networks, we devise a route-selection algorithm for forwarding data packets to the most appropriate attachment point to maximize collective battery lifetime and maintain load balancing. Results based on a detailed performance evaluation study are also presented here to demonstrate the efficacy of the proposed algorithms.

A flexible 100-antenna testbed for Massive MIMO

Abstract: Massive multiple-input multiple-output (MIMO) is one of the main candidates to be included in the fifth generation (5G) cellular systems. For further system development it is desirable to have real-time testbeds showing possibilities and limitations of the technology. In this paper we describe the Lund University Massive MIMO testbed — LuMaMi. It is a flexible testbed where the base station operates with up to 100 coherent radio-frequency transceiver chains based on software radio technology. Orthogonal Frequency Division Multiplex (OFDM) based signaling is used for each of the 10 simultaneous users served in the 20 MHz bandwidth. Real time MIMO precoding and decoding is distributed across 50 Xilinx Kintex-7 FPGAs with PCI-Express interconnects. The unique features of this system are: (i) high throughput processing of 384 Gbps of real time baseband data in both the transmit and receive directions, (ii) low-latency architecture with channel estimate to precoder turnaround of less than 500 micro seconds, and (iii) a flexible extension up to 128 antennas. We detail the design goals of the testbed, discuss the signaling and system architecture, and show initial measured results for a uplink Massive MIMO over-the-air transmission from four single-antenna UEs to 100 BS antennas.

El display and its driving method

Abstract: The invention relates to a method for terminal-assisted interference control in a mobile communication system employing multi-carrier techniques such as OFDM, the mobile communication system comprising a network (N) with a plurality of base stations (B1 to B3) controlled by a central entity (CE), and the base stations having means for communication with user terminals (T1 to T3) located inside their cell service area (C1 to C3). The central entity (CE) schedules time-frequency groups available, for data communication purposes between the terminals and the base station (B1 to B3), for the base stations under its control (B1 to 83) and for the terminals (T1 to T3) involved in the scheduling process. Scheduling decisions are made for each time interval (TI1 to TIn).

System and method for dynamically assigning channels for wireless packet communications

Abstract: A method and system for controlling media access in which a paging message is transmitted from a base station to a wireless station when a data packet is received for downlink transmission to the wireless station. The base station is one of a plurality of base stations and the wireless station is associated with the base station. In response to the paging message, a level of each of a plurality of pilot frequency signals is detected at the wireless station. Each pilot frequency corresponds to a downlink traffic channel and is transmitted by base stations to which the downlink traffic channel is assigned. The wireless station generates a list of preferred traffic channels based on a priority order of traffic channels and on detected levels of the pilot frequency signals, and transmits the list to the associated base station. A downlink traffic channel is assigned for downlink transmitting the received data packet to the wireless station based on the list of preferred traffic channels and updates a channel priority order list at the base station.