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Web Resources for Web Based Energy Information and Control Systems
Published in Barney L. Capehart, Timothy Middelkoop, Paul J. Allen, David C. Green, Handbook of Web Based Energy Information and Control Systems, 2020
“White-space” networking will start to develop into the next major wireless standard. When television broadcasting was exclusively analog the regulators of radio frequency bands required “white-space” or “guard bands” between the frequencies so as to “guard” against radio interference. Given broadcasting has gone primarily digital and is also “compressing” more signal into less frequency, the guard bands are no longer needed, thus opening up radio frequencies for “white-space networking.” Why the excitement and anticipation? Network speeds should be around 50-100MBps and above, thus easily accommodating streaming video and eliminating problems with VOIP quality. Seeing opportunities in new markets and new devices (called “white space devices” or WAD) all the big technology players are backing the endeavor: Google, Microsoft, Dell, Intel, Hewlett-Packard, etc.
Introduction
Published in Rajeshree Raut, Ranjit Sawant, Shriraghavan Madbushi, Cognitive Radio, 2020
Rajeshree Raut, Ranjit Sawant, Shriraghavan Madbushi
A CR is based on what is called a software defined radio (SDR) [3]. The software allows the radio to tune to different frequencies, power levels, and modulation depending upon its learning and the environment in which it operates. The CR is expected to perform the following four functions: Spectrum Sensing: detection of “white spaces” or the portion of spectrum vacant for use. This must also ensure that no primary user (licensed user) is operating at the same time.Spectrum Management: selection of the best spectrum hole for transmission.Spectrum Sharing: sharing of spectrum with other potential users.Spectrum Mobility: vacate the band when a licensed user is detected (spectrum handoff).
Cognitive Radio Networks: Concepts and Applications
Published in Nazmul Siddique, Syed Faraz Hasan, Salahuddin Muhammad Salim Zabir, Opportunistic Networking, 2017
S. M. Kamruzzaman, Abdullah Alghamdi, M. Anwar Hossain
A recent manifestation of DSA is in the TV spectrum. In 2008, the Federal Communications Commission (FCC) passed a historic ruling that allowed unlicensed devices (similar to Wi-Fi) to operate in the locally unoccupied TV spectrum (also called the TV white spaces or simply white spaces). Devices similar to the Wi-Fi devices of today are required to detect the available spectrum before using it for communication. According to the 2010 FCC Second Report and Order, the white space devices can detect available spectrum using either spectrum sensing or by querying a geolocation web service over the Internet [7].
Machine learning supervised antenna for software defined cognitive radios
Published in International Journal of Electronics, 2022
Pankaj Kumar Goswami, Garima Goswami
On application of a successful model, the spectrum can be allocated as per the priority encoder as shown in Figure 19. This indicates the maximum deviation in equivalence channel sharing probability between primary and secondary users. The channel scanning depends upon the occupancy by both the users and presented through user density for probability scaling. The colour variation from blue to red elaborates the high probability density (HPD) for channel occupancy from PU to SU. The white space indicates the possible availability of the vacant channel and the SDR system reconfigures antenna characteristics towards the white spacing. Based on white space scanning, ANN develops new scheduling of channel allocation and utilises available vacancy more effectively. At respective epochs, decision-based spectrum sensing leads the RF scanning via ANN-trained SDR system in WCRSN as shown in Figure 20.