Advantages And Disadvantages Of Spectrum Sensing

Spectrum sharing: Since there may be multiple CR users trying to access the spectrum, their transmissions should be coordinated to prevent collisions in overlapping

The increased demand for radio spectrum has resulted from the evolution of feature-rich and high-data-rate wireless applications. The spectrum is limited, and the current radio spectrum regulations make its use less productive. This has necessitated the development of dynamic spectrum allocation policies to make the utilization of the existing spectrum in a better way. As per the current spectrum allocation regulations, specific bands are assigned to particular services and only licensed users are granted access to licensed bands. Cognitive radio (CR) is expected to modernize the way spectrum is allocated. In a CR network, the cognitive radio part allows the unlicensed users (secondary users) to access spectrum bands allocated to the licensed

The four basic facts needed in order to understand the spectrum bands include; the license to use the spectrum bands are among the most flexible of any issued by the Federal Communications Commission (FCC). This means that the FCC permits any carriers within broad limits, to use them to provide any type of service using any type of technology. The second fact is that the services provided over these bands are market substitutes. For instance, when it comes to mobile telephone service providers, the data and mobile voice services provided by a company over a certain set of spectrum are the same with that provided by another company in their own set of spectrum.

The evolution of wireless technologies in modern days helps to utilize these kind of technology in many applications like vehicle safety application, a wireless data communication between the vehicles and also between the vehicles and other infrastructure.

Today we are in Fourth Generation; it is categorized based on its characteristic services and features like transmission signals, data transmission rate, bandwidth frequency and nature of the services provided. First generation (1G) is introduced in 1980, so each generation had been comes at the end of every decade. First generation used analog signals, circuit switching and FDMA with 30 kHz channels occupying the 824MHz 894MHz frequency band .First generation supports only voice transmission .The data was not reliable; there were interrupted communication and few other problems in First Generation [1]. Second Generation (2G) technology was established in 1990, which used digital signals for transmission and two digital modulation schemes TDMA and CDMA with circuit switched network . Second Generation uses the existing radio spectrum to provide the services. It was developed to overcome the previous generation’s drawbacks, and to have data and voice transmission. But this generation also has few drawbacks like

Angle modulation is a technique in which the angle of the carrier wave is varied according to the instantaneous amplitude of the modulating signal. There are two types of angle modulation.

Each access point can practically service between 32 to 64 users, depending upon manufacturer. The bandwidth will be shared by all users. The number of radio channels associated with each technology will vary by technology and product manufacturer. Multiple channels allows for multiple access points to be collocated in order to provide access for a larger number of users.

Radiofrequency identifies the subject by reading the tags attached to the subject. These tags contain electronically stored information which is captured by the reader. Tags may either be powered by electromagnetic induction, some may collect energy from the interrogating radio waves and act as passive transponder and some are powered by batteries and can operate at hundreds of

Forward: The Public Safety Wireless Network (PSWN) Program is conducting an ongoing assessment of advancements in the wireless communications industry. The scope of this assessment is to identify emerging wireless services and technologies for potential public safety use in the near future and beyond. This particular document is the first of a series of emerging wireless technologies studies. This study will concentrate primarily on the fourth generation of mobile telecommunications and beyond.

Wireless communication is nowadays widely utilized in many high-performance devices and remote sensing systems, comprising radar sensors

Satellite Band Radio (SBR) Satellite Band Radios are virtually unheard off in our country. these radios are like normal radios but use satellites to transmit there information instead of the normal analog radio waves used.

Software Defined Radio is a Radio in which some or all of the physical layer functions are software defined [3]

In RADAR the transmitter generates an electromagnetic signal that is radiated into space by an antenna. A portion of the transmitted energy is intercepted by the target and

I Saksham Gupta student of B.Tech Electronic and Communication hereby declare that the project titled “Software defined radio for RFID” which is submitted by me to Department of Amity School of engineering and technology (ASET), Amity University Uttar Pradesh, Noida, in partial fulfillment of requirement for the award of the degree of Bachelor of Technology in B.Tech Electronic and Communication, has not been previously formed the basis for the award of any degree, diploma or other similar title or recognition.The Author attests that permission has been obtained for the use of any copy righted material appearing in the Dissertation / Project report other than brief excerpts requiring only proper acknowledgement in scholarly writing and all such use is acknowledged.

Abstract−A WIRELESS BODY AREA NETWORK (WBAN) is a wireless sensor network technology that is confined to body of a person under supervision. As we use ISM band for transmission of information for WBAN thus it is a huge possibility that the transmission can undergo interference that affect the transmission. Hence there is a major utility of combining cognitive radio with WBAN. In this report, we discuss the role of cognitive radio in WBAN and how this can enhance the transmission of WBAN. We will also discuss various algorithms for sensing and thus will compare them.