What is energy detection?
When a device plans to transmit a signal, it first goes into receive mode to detect and estimate the signal energy level in the desired channel. This task is known an energy detection (ED).
What is spectrum sensing techniques?
Classification of Spectrum Sensing Techniques Spectrum Sensing techniques are classified into three main types, transmitter detection or non cooperative sensing, cooperative sensing and interference based sensing.
What is cooperative spectrum sensing?
1. Cooperative sensing is a solution to enhance the detection performance, in which secondary users collaborate with each other to sense the spectrum to find the spectrum holes. Learn more in: Interference Statistics and Capacity-Outage Analysis in Cognitive Radio Networks. 2.
What is spectrum sharing?
Spectrum sharing is the logical partitioning of optical spectrum on a submarine cable for different end-users, such that each end-user has its own ‘virtual fiber pair. ‘ Virtualization has revolutionized IT operations in companies around the world.
What is spectrum radio cognitive?
Spectrum sensing is one of the most important processes performed by cognitive radio systems. It. allows the SUs to learn about the radio environment by detecting the presence of the PU signals. using one or multiple techniques and decide to transmit or not in its frequency band [1-5].
What are the techniques used in spectrum sharing?
The spectrum sharing techniques can be classified as: interweave, underlay, and overlay [6]. In interweave spectrum sharing; the secondary system can dynamically access the spectrum holes. For spectrum underlay, secondary users (SUs) are simultaneously transmitting with the primary users (PUs).
Why is spectrum sensing needed?
Spectrum sensing is a key function of cognitive radio to prevent the harmful interference with licensed users and identify the available spectrum for improving the spectrum’s utilization. However, detection performance in practice is often compromised with multipath fading, shadowing and receiver uncertainty issues.
What type of antenna is used in cognitive radio?
] a quad-band antenna for cognitive radio is presented. It has a direction radiation pattern in four frequency bands, covering most of the spectrum used for existing wireless applications. MEMS switch is used to adjust the operating frequency of the quad-band antenna.
What is spectrum sharing in telecom?
Spectrum sharing is the simultaneous usage of a specific radio frequency band in a specific geographical area by a number of independent entities. Simply, it is the “cooperative use of common spectrum” by multiple users. Spectrum sharing also can take many forms, coordinated and uncoordinated.
What is a spectrum sensor?
Chip-scale spectral sensing systems enable many existing and emerging applications, such as color picking, authentication and spectral analysis of substances, materials, foods and fluids. These systems are being adopted in the consumer, industrial and medical sectors.
What is Wideband spectrum sensing?
Sensing the wideband spectrum is an important process for next-generation wireless communication systems. Spectrum sensing primarily aims at detecting unused spectrum holes over wide frequency bands so that secondary users can use them to meet their requirements in terms of quality-of-service.
How does a cognitive radio work?
Cognitive radio (CR) is a form of wireless communication in which a transceiver can intelligently detect which communication channels are in use and which are not. It instantly moves into vacant channels while avoiding occupied ones. It does not cause any interference to the licensed user.