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Learning under Random Updates
Published in Hamidou Tembine, Distributed Strategic Learning for Wireless Engineers, 2018
Wireless technology is proliferating rapidly, and the vision of pervasive wireless computing and communications offers the promise of many industrial and individual benefits. While consumer devices such as cell phones, personal data assistants (PDAs), and laptops receive a lot of attention, the impact of wireless technology is much broader, e.g., through sensor networks for safety applications, vehicular networks, smart grid control, home automation, medical wearable and embedded wireless devices, and entertainment systems. This explosion of wireless applications creates an ever-increasing demand for more radio spectrum. However, most easily usable spectrum bands have been allocated, although many measurements, nevertheless, show that at any specific time and location, these spectrum bands are significantly underutilized and a lot of energy is wasted.
Introduction
Published in P. S. Neelakanta, ATM Telecommunications, 2018
At the international level, the telecommunication standards are set forth by the International Telecommunication Union (ITU) with the CCITT establishing recommendations on telephony, telegraphy and data communication systems and the Conference of European Posts and Telecommunications Administration (CEPT) establishing the CCITT-based standards. The subcommittees of the International Standards Organization (ISO) of the United Nations also work closely with CCITT in formulating telecommunication standards. In regards to the wireless (radio) spectrum-related issues, they are governed by the International Radio Consultative Committee (CCIR). In the United States, the FCC manages the radio spectrum.
Radio Frequency Spectrum
Published in Saad Z. Asif, 5G Mobile Communications Concepts and Technologies, 2018
Mobile communication depends on the radio spectrum to carry out its tasks. The term radio spectrum refers to the frequency range from 3 kHz to 300 GHz corresponding to wavelengths ranging from 100 km to 1 mm. The exchange of information takes place by varying the amplitude, phase, and frequency of carrier radio waves. This radio spectrum is one of the most tightly regulated resources of today's world. From cell phones to broadcasting TV sets, microwave ovens to garage door openers, maritime affairs to flight tracking, virtually every wireless piece of communication depends on access to the radio frequency spectrum.
A Novel Hardware Efficient High Resolution Spectrum Hole Detection Technique for Cognitive Radio
Published in International Journal of Electronics, 2023
Sushmitha Sajeevu, Sakthivel Vellaisamy
In a country, spectrum is allocated by government agencies for defence, satellite operators, aviation, railways, service providers (Bhattarai et al., 2016). Conventionally, different regions of the radio spectrum with specific bandwidth are allocated to different services. With such an allocation only the licenced user can utilise the spectrum assigned to that particular service irrespective of whether the licenced user is active or not. Even though this particular allocation reduces the interference among different services, efficient utilisation of spectrum cannot be achieved through this conventional allocation. Studies conducted worldwide such as Singapore, US, China, New Zealand and Germany have disclosed that a huge amount of the alloted spectrum is inefficiently utilised (El Rharras et al., 2020). It can be inferred that the under utilisation of the spectrum contributes to this spectrum crunch even more than the physical shortage of the spectrum.
HBRO-AlexNet: Honey Badger Remora Optimization Integrated AlexNet for Cooperative Spectrum Sensing in Cognitive Radio Network
Published in Cybernetics and Systems, 2023
Neelam Dewangan, Arun Kumar, R.N. Patel
The growth of wireless communication and its uses is what is increasing the need for the radio spectrum. In order to manage the difficulties with the available spectrum, CR technology is designed to find and distribute free spectrum channels. This research introduces a cooperative spectrum sensing technique in CRN to improve spectrum efficiency by using licensed spectrum bands in SU when PUs are inactive. Designing test statistics to improve the chance of detection and improve spectrum efficiency is a significant problem in spectrum sensing. Dynamic spectrum access is more common in CRN for permitting SU in licensed bands because of the increasing user count. A proposed HBRO-based AlexNet is presented to perform the task of spectrum sensing in CRN to improve spectrum efficiency. HBRO, which is modeled by incorporating the HBA and ROA, is used to perform AlexNet's training process. This method improves the precision of optimization and results in effective convergence. The hybrid optimization approach modifies the solution based on the fitness measure and trains the classifier. For the Rician channel at SNR of 5 dB, the proposed method also yields 1, 0,999, 562.8, and 214.4 s for the chance of detection, the probability of a false alarm, processing time, and sensing time. Future research will take into account another deep learning method to locate free spectrum in CR and apply it in a practical setting.