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Wireless Networks
Published in Vikas Kumar Jha, Bishwajeet Pandey, Ciro Rodriguez Rodriguez, Network Evolution and Applications, 2023
Vikas Kumar Jha, Bishwajeet Pandey, Ciro Rodriguez Rodriguez
A WLAN is a wireless network used to link two or more network devices wirelessly within a limited area such as a home, school, laboratory, campus, or office to form a LAN. This provides users mobility as an added advantage over the wired LAN so that the user can move around within the coverage area and be connected to the network. Using an Internet gateway, a WLAN user can be provided Internet connection. WLAN technology is very popular now as earlier it was used within offices and homes and now is preferred almost everywhere within premises or buildings for wireless network access such as in the shops, stores, shopping malls, and restaurants. At the same time, COVID-19 pandemic has forced office workers, students, teachers, and others to work and study from home and that has greatly increased the use of wireless home networks.
Green Hybrid Wireless-Optical Broadband Networks
Published in Gurjit Kaur, Akanksha Srivastava, Green Communication Technologies for Future Networks, 2023
The most famous wireless access technologies are WiFi and WiMAX. WiFi is a wireless local area network (WLAN) based on the IEEE 802.11 standard that was established in the 1990s. It is used extensively in the last 15 years due to cheaper, ease to deployment, high speed data rate. Other standards for WiFi are IEEE 802.11a/b/g/n/y. These standards are different in terms of their data rates and operating frequencies. IEEE 802.11a works at an unlicensed band of 5 GHz with utmost 54 Mbps data rate of. IEEE 802.11b/g operate at a 2.5 GHz unlicensed band along with 11 Mbps/54 Mbps data rate (Srivastava et al. 2020). But IEEE 802.11n offers a total 600 Mbps of data rate, which operates at 2.4 GHz or 5 GHz and IEEE 802.11y is currently a work in progress for the 54 Mbps data rate, which operates at 3.7 GHz with maximum transmission reach of 5 km for outdoor environment. The limited transmission range for other standards is from 100 m–200 m.
Seamless and Secure Communication for 5G Subscribers in 5G-WLAN Heterogeneous Networks
Published in Mahmoud Elkhodr, Qusay F. Hassan, Seyed Shahrestani, Networks of the Future, 2017
A WLAN is a wireless computer network that connects at least two gadgets utilizing high-frequency radio waves within a limited region (e.g., school, home, office building, and computer laboratory). This gives a client the capability to move around in a local coverage area while connected to the WLAN and can provide a link to the Internet. Most advanced WLANs are dependent on IEEE 802.11 guidelines, advertised under the Wi-Fi [12] brand name. A WLAN is, in all simplicity, a cable replacement technology that provides typical client devices, such as mobiles, PDA with means to move freely inside the coverage area while maintaining connectivity to the wireless network. The IEEE 802.11 is a collection of physical layer specifications and media access control for imposing WLAN communications' different frequency bands, including 2.4, 3.6, 5.8, and 60 GHz and 900 MHz. The specifications are standardized by the Institute of Electrical and Electronics Engineers' WLAN Standards Committee. The base edition of the WLAN standard was launched in 1997 [12] and has had subsequent amendments [13]. Since then, a progression of IEEE 802.11 guidelines has been proposed to enhance the efficiency of WLAN. The following is a list of a few of those standards.
Use of real time localization systems (RTLS) in the automotive production and the prospects of 5G – A literature review
Published in Production & Manufacturing Research, 2022
Christoph Küpper, Janina Rösch, Herwig Winkler
Wi-Fi is a Wireless Lan Area Network (WLAN) and common technology in broadband communications (Haotai Sun et al., 2020). It uses unlicensed frequencies in the range of 2.4 GHz and 5 GHz (Ning et al., 2013), and with the newest evolution of the standard IEEE 802.11ax also 6 GHz bands (Lee et al., 2019). A benefit of using Wi-Fi is its simple off-the-shelf availability and widespread usage with existing infrastructure (Bakri et al., 2020; Sosa-Sesma & Perez-Navarro, 2016). WLAN uses positioning as a secondary function next to the communication purpose (Hilty et al., 2012). Positioning methods include AOA (Cidronali et al., 2010), triangulation (Rusli et al., 2016; Wang Yuan et al., 2014), RSSI- based fingerprinting (Ren et al., 2019a, 2019b) and CSI-based fingerprinting (Hao Chen et al., 2017; Shi et al., 2018). From these methods, fingerprinting provides the best performance and allows for easy implementation and NLOS measurements without specialized hardware (Jaffe & Wax, 2014; Laoudias et al., 2018b). The accuracy is provided with about 2 ~ 3 m but can be heavily affected by barriers, multipaths of crowdedness, and the scanning time of 3 ~ 4 seconds by smartphones, resulting in low refreshment rates (Byunghun et al., 2015).
Health effects of WiFi radiation: a review based on systematic quality evaluation
Published in Critical Reviews in Environmental Science and Technology, 2022
Stefan Dongus, Hamed Jalilian, David Schürmann, Martin Röösli
WiFi, also called WLAN (Wireless Local Area Network), is commonly used to connect devices and for Internet access. Typical applications are in private homes, schools, workplaces, and WiFi hotspots in cities and public transport. WiFi is based on the IEEE 802.11 family of standards, which uses various transmission protocols mostly in the frequency range of 2.400 to 2.484 GHz and 5.150 to 5.825 GHz (IEEE, 2016). Data packets are transmitted between multiple devices and access points using various types of modulations such as the multiple-input, multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM). Consequently, WLAN devices transmit short pulses (bursts) and the burst lengths and burst repetition rates are highly dependent on the actual data traffic in the network. The duty factor is the ratio of the pulse duration to the total period, which is usually low for WiFi communication (Khalid et al., 2011). In the absence of data traffic, only the access point transmits a short beacon signal, every 100 ms, which corresponds to a pulse rate of 10 Hz. In this situation, the crest factor, defined as the ratio of peak values to the effective value, is highest (about a factor of 100) (Schmid et al., 2020).
Technology review: prototyping platforms for monitoring ambient conditions
Published in International Journal of Environmental Health Research, 2018
Samuel Olaiya Afolaranmi, Borja Ramis Ferrer, Jose Luis Martinez Lastra
In the sensing of data, Wireless Sensor Networks (WSN), Wireless Local Area Network (WLAN17) and Mobile networks18 are the available standards often used to create the sensor network. WSN possess excellent qualities such as low power, low cost, low energy consumption and possibility of node extension. It can also be deployed in harsh environments. However, low computing capability and short communication range (about 10–100 m) are some of its weaknesses. Typical technologies for WSN include ZigBee, Bluetooth19 and 6LowPAN.20 WLAN offers a wider communication range and better speed than WSN. It is used for setting up local networks where several devices are networked. It also provides connection to the internet. However, problems such as interference from other WLAN and security risk are some of its drawbacks. The main technology in WLAN is Wi-Fi. Mobile networks cover even a greater distance than WSN and WLAN. Mobile networks are typically cellular networks and offers as far as global coverage. Typical technologies include 2G, 3G and 4G, etc. networks and they are usually more expensive. For indoor ambient condition monitoring, the use of mobile networks is a far too expensive option. The devices used for indoor monitoring requires low power and short coverage distance. Therefore, a hybrid sensor network that combines WSN and WLAN may provide quality network for monitoring indoor ambient conditions. WSN can be used to set-up communication between different sensors while WLAN can be used for providing connection to the Internet.