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Sources of Radio Frequency Radiation
Published in Riadh W. Y. Habash, Electromagnetic Fields and Radiation, 2018
The basic structure of the cellular network includes telephone systems and radio services. Where mobile radio operates in a closed network and has no access to the telephone system, cellular system allows interconnection to the telephone network. Figure 6-14 shows a typical topology for the cellular system. The main parts of the cellular system are radio link, switching system, database, processing center, and external network. The mobile connection of the cellular subscriber and fixed network is realized with radio links. The mobile station (MS) is usually a small handset. It corresponds with the base transceiver station (BTS). Each cell site has a BTS with a transceiver and antenna system.
Authentication in Wireless Networks
Published in Yang Xiao, Security in Distributed, Grid, Mobile, and Pervasive Computing, 2007
Saikat Chakrabarti, Venkata C. Giruka, Mukesh Singhal
The BTS contains radio transceivers and engages in radio-link protocols with the mobile station. BSC controls and manages the radio resources of several BTSs. The BSC is responsible for radio channel setup, frequency hopping and handovers between two BTSs that the BSC controls. There can be several BSCs in a BSS, as shown in Figure 5.1.
The Pan-European Cellular System
Published in Jerry D. Gibson, The Communications Handbook, 2018
The BS is divided functionally into a number of base transceiver stations (BTS) and a base station controller (BSC). The BS is responsible for channel allocation (R.05.09), link quality and power budget control (R.05.06 and R.05.08), signalling and broadcast traffic control, frequency hopping (FH) (R.05.02), handover (HO) initiation (R.03.09 and R.05.08), etc. The MSC represents the gateway to other networks, such as the public switched telephone network (PSTN), integrated services digital network (ISDN) and packet data networks using the interworking functions standardized in recommendation R.09. The MSC's further functions include paging, MS location updating (R.03.12), HO control (R.03.09), etc. The MS's mobility management is assisted by the home location register (HLR) (R.03.12), storing part of the MS's location information and routing incoming calls to the visitor location register (VLR) (R.03.12) in charge of the area, where the paged MS roams. Location update is asked for by the MS, whenever it detects from the received and decoded broadcast control channel (BCCH) messages that it entered a new location area. The HLR contains, amongst a number of other parameters, the international mobile subscriber identity (IMSI), which is used for the authentication (R.03.20) of the subscriber by his authentication center (AUC). This enables the system to confirm that the subscriber is allowed to access it. Every subscriber belongs to a home network and the specific services that the subscriber is allowed to use are entered into his HLR. The equipment identity register (EIR) allows for stolen, fraudulent, or faulty mobile stations to be identified by the network operators. The VLR is the functional unit that attends to a MS operating outside the area of its HLR. The visiting MS is automatically registered at the nearest MSC, and the VLR is informed of the MSs arrival. A roaming number is then assigned to the MS, and this enables calls to be routed to it. The operations and maintenance center (OMC), network management center (NMC) and administration center (ADC) are the functional entities through which the system is monitored, controlled, maintained and managed (R.12).
Cloud assisted Internet of things intelligent transportation system and the traffic control system in the smart city
Published in Journal of Control and Decision, 2023
Figure 2 demonstrate the Proposed CIoT-ITS. The driver becomes a passenger during automatic driving, making it easier to work. Traffic flows are cooperative driving application where autonomous cars follow the same lanes, maintaining a continuous space of small inter-vehicles, minimising fuel consumption and gas emissions, and ensuring safe and effective transportation. The result is similar to a wireless-connected car that implies that the following vehicle will automatically stop, steer and accelerate due to the leading car's movement. The sensors equipped on the vehicle transmit the data gathered to the nearby Roadside unit (RSU) and then summarises the data for processing to the cloud server. The cloud architecture is used to efficiently monitor data movements, vehicle densities, flow time, waiting time for cluster nodes that serve as an agent, gather traffic information from all node platforms, and guide it to a base station where data can be collected for processing in the data centre. A roadside unit (RSU) gathers traffic data from static sensing and transmits the data to traffic control systems and a central traffic control centre. These systems provide an intelligence centre for smart cars to gather information about potential traffic. An RSU technically consists of the Base Station Controller (BSC) traffic control function, and the Base Transmitting Station (BTS) receipt/transmitting traffic control function. The BTS is the reception and transmitting equipment and covers a cell. Traffic sensors are used to gather information on road traffic for signal control, and the collected data is transmitted to the Vehicle Information and Communication System Centre. In the maintenance of road networks, CCTV cameras play a significant role. They are built at sensitive points in the network to assist transport management, with regular congestion and traffic queues. Server load balancing helps manage high-volume traffic efficiently through servers, preventing lower load times and accessibility issues. Organisations will increase the throughput and application responses by correctly spreading network and web traffic to more than one host. Following the sensor data analysis, the device controller sets the traffic signal time by an algorithm for traffic management. Probable traffic congestion can be expected at the intersection. In this proposed model, there are consisting of two preposition model. i) vehicle speed and traffic calculation model ii) traffic Prediction model.