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.

Efficient Data Gathering with Mobile Collectors and Space-Division Multiple Access Technique in Wireless Sensor Networks

Abstract: Recent years have witnessed a surge of interest in efficient data gathering schemes in wireless sensor networks (WSNs). In this paper, we address this issue by adopting mobility and space-division multiple access (SDMA) technique. Specifically, mobile collectors, called SenCars in this paper, work like mobile base stations and collect data from associated sensors via single-hop transmissions so as to achieve uniform energy consumption. We also apply SDMA technique to data gathering by equipping each SenCar with multiple antennas such that distinct compatible sensors may successfully make concurrent data uploading to a SenCar. To investigate the utility of the joint design of controlled mobility and SDMA technique, we consider two cases, where a single SenCar and multiple SenCars are deployed in a WSN, respectively. For the single SenCar case, we aim to minimize the total data gathering time, which consists of the moving time of the SenCar and the data uploading time of sensors, by exploring the trade-off between the shortest moving tour and the full utilization of SDMA. We refer to this problem as mobile data gathering with SDMA, or MDG-SDMA for short. We formalize it into an integer linear program (ILP) and propose three heuristic algorithms for it. In the multi-SenCar case, the sensing field is divided into several regions, each having a SenCar. We focus on minimizing the maximum data gathering time among different regions and refer to it as mobile data gathering with multiple SenCars and SDMA (MDG-MS) problem. Accordingly, we propose a region-division and tour-planning (RDTP) algorithm in which data gathering time is balanced among different regions. We carry out extensive simulations and the results demonstrate that our proposed algorithms significantly outperform single SenCar and non-SDMA schemes.

Method and apparatus for controlling transmit power thresholds based on classification of wireless communication subscribers

Abstract: The present invention provides a method and apparatus for allowing a base station or base station controller to adjust transmissions to fixed location subscribers in closed-loop communication systems. In a closed-loop communication system, a base station exchanges signals with both fixed location and mobile user stations. When a user or subscriber initially registers with the base station, the base station determines a status of this subscriber based on, for example, an electronic serial number transmitted to the base station. The base station compares the electronic serial number to a database (Home Location Register) which determines whether the user corresponds to a fixed station or a mobile station. If the user is a fixed station, then the base station lowers nominal and minimum power level thresholds. Based on the lowered thresholds, the base station thereafter transmits forward link signals to the fixed station at a lower power level. As a result, the base station can increase its capacity due to the lower overall power rate.

Hybrid Backscatter Communication for Wireless-Powered Heterogeneous Networks

Abstract: In this paper, we propose hybrid backscatter communication for wireless-powered communication networks (WPCNs) to increase transmission range and provide uniform rate distribution in the heterogeneous network (HetNet) environment. In such HetNet, where the TV tower or high-power base station (macrocell) coexists with densely deployed small-power access points (e.g., small-cells or WiFi), users can operate in either bistatic scatter or ambient backscatter, or a hybrid of them, given that the harvested energy from the dedicated or ambient RF signals may not be sufficient enough to support the existing harvest-then-transmit protocol for WPCN, which is extended to the wireless-powered heterogeneous network (WPHetNet). Considering the hybrid and dual mode operation, we formulate a throughput maximization problem depending on the user location, namely Macro-zone or WiFi-zone. After performing the optimal time allocation for the above operation, we show that the proposed hybrid backscatter communication can increase the transmission range of WPHetNet, while achieving uniform rate distribution.

Handover of direct peer to peer communication

Abstract: Methods and apparatus, including computer program products, are provided for D2D handovers. The method may include sending to a target base station a handover request message including a proposed common identifier for a device-to-device pair and a proposed allocation of radio resources for the device-to-device pair; receiving, from the target base station in response to the handover request message, a handover request reply message including a confirmation of the proposed allocation and of the proposed common identifier; sending to a first device of the device-to-device pair a handover command including the proposed allocation and the proposed common identifier; receiving, from a second device of the device-to-device pair, a measurement report representative of the target base station; and determining whether to initiate a handover of the second device to the target base station, wherein when the handover is initiated, the first device of the device-to-device pair and the second device of the device-to-device pair are handed over to the target base station. Related apparatus, systems, methods, and articles are also described.

Methods and apparatus for synchronization in a wireless network

Abstract: As part of a preferred communication protocol, base stations (12) which are synchronized to a PSTN (20) of a wireless communication network (10), periodically transmit a preamble. A remote detects the preamble and, upon verification of the data contained in the base station transmission, sets its counter to an initialized state based on the received preamble. An early/late analysis of each subsequently received base station timing pulse is used to adjust both the mobile station timing and to adjust the output frequency of the mobile station master clock and codec clock to effectively maintain end to end synchronization with the respective base station and the PSTN throughout the duration of an established communication link.