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"Contents :- Chapter 1 A Hollywood Story - Chapter 2 The Frequency Spectrum and the Secure Placement of Calls - Chapter 3 Basic Modulation Schemes - Chapter 4 Advanced Modulation and Encoding Schemes - Chapter 5 Spreading the Signal across the Frequencies - Chapter 6 The IEEE 802.11 Wireless LAN Standard - Chapter 7 IEEE 802.11a, 802.11b, and 802.11g WLANs - Chapter 8 802.11 Wireless LAN Designs - Chapter 9 Wireless Metropolitan-Area Networks - Chapter 10 Security for 802.11 Wireless LANs - Chapter 11 Future Trends in Wireless LANs - Chapter 12 Conclusion - References - Appendix Wireless Access Point and Router Vendors and Products "

"An important aspect of the Wireless Local Area Network’s (WLAN) physical layer design is its Peak-to-Average Power Ratio (PAPR) that has an important role in the power amplifier’s linearity and efficiency. This paper analyses the PAPR of IEEE 802.11n standard which has some different packet formats for backward compatibility. PAPR calculation is limited to the Legacy and High Throughput (HT) formats of a 20MHz bandwidth. Calculation results show that a high probability for the maximum PAPR exists in the signal field rather than in the preamble or data fields. Furthermore, the maximum PAPR for the signal field of a Legacy format 802.11n is 29.3dB that appears when the data rate is 6Mbps and data length is 3846 octet. However, the maximum PAPR for the high throughput (HT) format is 35.6dB that is related to a data rate of 6.5Mbps and a data length of 32768 octets. Moreover, the PAPR of the HT-format is 3dB higher than the Legacy format for CCDF 10-2."

"Pertumbuhan pengguna Internet sangat signifikan selama hampir dua dekade terakhir ini. Pertumbuhan ini didukung oleh kemudahan instalasi perangkat serta fleksibilitas aksesnya. Teknologi pendukung yang demikian itu adalah WLAN. Ekspansi area cakupan WLAN menggunakan medium serat optik membentuk jaringan hibrida yang disebut WiLANoF menemui masalah pada protokolnya. Diperlukan suatu rekayasa protokol untuk menyelesaikan masalah tersebut. Transmisi aplikasi yang berbeda memiliki persyaratan yang berbeda pula. Aplikasi elastik menggunakan protokol 802.11g DCF, sedangkan aplikasi waktu nyata menggunakan 802.11e HCCA. Untuk menjaga throughput, delay yang dihasilkan dirancang agar tidak melebihi suatu nilai tertentu yang tergantung pada persyaratan aplikasi. Dalam riset ini diusulkan prosedur komputasi 802.11b/g yang mempermudah proses desain dan pengendalian protokol DCF WiLANoF. Di samping, itu diusulkan suatu pendekatan baru yaitu optimasi TXOP menggunakan metode Knapsack untuk menghasilkan utilisasi kanal yang tinggi pada protokol HCCA. Hasil analisis penggunaan prosedur komputasi 802.11 b/g untuk aplikasi elastik pada WiLANoF menunjukkan bahwa delay bound dipengaruhi oleh kelas dan mode operasi WLAN, skema CSMA/CA serta ukuran frame. Delay pada teknologi ERP-OFDM skema basic access 483 µs dan RTS/CTS 649 µs, dicapai untuk kondisi panjang frame 1500 byte, panjang serat optik 3780 m dan timeout 43 µs. Untuk teknologi DSSS-OFDM 54 Mbps mengalami delay skema basic access 1,2 ms dan RTS/CTS 2,05 ms untuk kondisi panjang frame 1500 byte, panjang serat optik 21,7 km dan timeout 22,2 ms. Optimasi TXOP aplikasi waktu- nyata menggunakan metode Knapsack berfungsi untuk mengendalikan parameter delay sehingga utilisasi kanal maksimum dapat dicapai. Hasil yang diperoleh adalah 22 TXOP untuk 45 TU CFP dan 4 laju mandatory, sedangkan panjang serat optik mencapai 1700 m.

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The growth of Internet users are very significant for the last two decades. This growth may be supported by the installation easiness and the access flexibility of the Internet technologies. Such supporting technologies are Wireless-Local Area Network (WLAN). The optical fiber applications in the expansion of WLAN coverage area which is then called WLAN-over-Fiber (WiLANoF) encounter some problems due to the protocols. To resolve such protocol problems, a protocol engineering is required. The transmission of different applications have different requirements. The elastic applications transmission is carried out by 802.11g DCF protocol, while the real-time applications is managed by 802.11e HCCA protocol. To maintain the network throughput, the resulting delay is designed not to exceed a certain value which depends on the application requirements. This research proposes a B/G computing procedure that simplify the design process and the control of WiLANoF DCF protocol. In addition, it is also proposed a TXOP optimation that uses Knapsack method to produce high channel utilization upon the HCCA protocol.

The analysis results using the B/G computational procedures for elastic applications show that the WiLANoF delay bound is influenced by the class and the operation mode of WLAN, the CSMA/CA scheme as well as the size of the payload frames. The delay of 54 Mbps ERP-OFDM is 483 µs using the scheme of basic access, while the RTS/CTS is 649 µs. The both results are achieved under the conditions of 1500 byte frame length, 3780 m optical fiber length and the 43 µs timeout. The delay of 54 Mbps DSSS-OFDM is 1.2 ms upon the scheme of basic access, while the RTS/CTS is 2.05 ms. The last couple results are under the circumstances of 1500 bytes frame length, 21.7 km optical fiber length and 22.2 ms timeout. The TXOP optimation using the Knapsack method for real-time applications, can be used to control the delay parameter so that the maximum channel utilization can be achieved. The results obtained are 22 TXOP to 45 TU CFP and 4 mandatory rates, while the length of the optical fiber reaches 1700 m."

"Wireless networking technologies are witnessed to become the integral part of industry, business, entertainment and daily life. Encyclopedia of Wireless Networks is expected to provide comprehensive references to key concepts of wireless networks, including research results of historical significance, areas of current interests, and growing directions in the future wireless networks. It can serve as a valuable and authoritative literature for students, researchers, engineers, and practitioners who need a quick reference to the subjects of wireless network technology and its relevant applications. "

"If you've been searching for a way to get up to speed on IEEE 802.11n and 802.11ac WLAN standards without having to wade through the entire specification, then look no further. This comprehensive overview describes the underlying principles, implementation details and key enhancing features of 802.11n and 802.11ac. For many of these features the authors outline the motivation and history behind their adoption into the standard. A detailed discussion of key throughput, robustness, and reliability enhancing features (such as MIMO, multi-user MIMO, 40/​80/​160 MHz channels, transmit beamforming and packet aggregation) is given, plus clear summaries of issues surrounding legacy interoperability and coexistence. Now updated and significantly revised, this 2nd edition contains new material on 802.11ac throughput, including revised chapters on MAC and interoperability, plus new chapters on 802.11ac PHY and multi-user MIMO. An ideal reference for designers of WLAN equipment, network managers, and researchers in the field of wireless communications""

"This SpringerBrief introduces the basics of wireless powered communication networks (WPCNs). In particular, the background and concept of WPCNs are briefly discussed. Moreover, this brief provides an extensive study of the recent developments in this area from an optimization perspective. Wireless powered communication network (WPCN) is a new network paradigm for IoT, where wireless devices (WDs) are powered by radio frequency (RF) based wireless power transfer (WPT) to eliminate the need for recharging or replacing the batteries manually and to prolong their lifetime.In this context, the brief also discusses some optimization problems for state-of-the-art scenarios of wireless powered communication networks.The target audiences for this SpringerBrief are researchers, engineers, and undergraduate and graduate-level students, who are studying or working in wireless powered communication networks and its performance optimization."

"Interworking of Wireless LANs and Cellular Networks focuses on three aspects, namely access selection, call admission control and load sharing to investigate heterogeneous interworking for cellular/WLAN integrated networks. It not only reveals important observations but also offers useful tools for performance evaluation. The unique traffic and network characteristics are exploited to enhance interworking effectiveness. Theoretical analysis and simulation validation demonstrate benefits of cellular/WLAN interworking in real networks. Last but not the least, this brief highlights promising future research directions to guide interested readers."

"This monograph develops a framework for modeling and solving utility maximization problems in nonconvex wireless systems. The first part develops a model for utility optimization in wireless systems. The model is general enough to encompass a wide array of system configurations and performance objectives. Based on the general model, a set of methods for solving utility maximization problems is developed in the second part of the book. The development is based on a careful examination of the properties that are required for the application of each method. This part focuses on problems whose initial formulation does not allow for a solution by standard methods and discusses alternative approaches. The last part presents two case studies to demonstrate the application of the proposed framework. In both cases, utility maximization in multi-antenna broadcast channels is investigated."