The advance of wireless communications brings in various schemes of wireless digital communication technology. Analog communication and broadcasting services convert into digital services in many countries. The IBOC (InBand On-Channel) system has been developed to work in the same band with the conventional analog radio and broadcasting digital signal simultaneously. HDR (HD-Radio) standard of ...

The introduction of new communication techniques requires an increase in the efficiency of spectrum usage. Cognitive radio is one of the new techniques that fosters spectrum efficiency by using unoccupied frequency spectrum for communications. However, cognitive radio will increase the transmission power density and cause an increasing level of Radio Frequency Interference (RFI), which may impa...

Adaptive and cognitive radios (CR) have been becoming popular for optimizing mobile radio system transmission and reception. One of the most important elements of the adaptive radio and CR concepts is the ability to measure, sense, learn about, and be aware of parameters related to the radio channel characteristics, availability of spectrum and power, interference and noise temperature, operati...

In this thesis we investigate the feasibility of using information overheard by wireless devices to reduce their overall energy consumption for communications. Specifically we investigate the hypothesis “It is more efficient in terms of energy consumption to constrain the transmission power based upon a combination of received signal strength with a minimally extended MAC, than to utilise an un...

Cognitive radio reduces the spectral inefficiency by sensing the under and over utilized parts of the spectrum and then redistributing the transmission to ensure that the spectrum is used efficiently. The awareness about spectrum usage is obtained by spectrum sensing. Cyclostationary feature detections one of the spectrum sensing techniques for cognitive radio. In this paper, we detect the pres...

Ultra-Wideband1 (UWB) is a radio transmission scheme that uses extremely low power pulses of radio energy spread across a wide spectrum of frequencies. UWB has several advantages over conventional continuous wave radio communications including potential support for high data rates, robustness to multipath interference and fading. We present an overview of UWB technology and its use in data comm...

During the last decades, the demand for higher data rates in wireless communication systems grew steadily. While the number of communication systems increased significantly, the amount of available spectral resources has remained constant. To exploit spectral resources more efficiently, cognitive radio concepts have become of utmost interest. The goal of cognitive radio systems is to sense the ...

Cognitive radio is an enabling technology of dynamic spectrum access (DSA) networking. In DSA, unlicensed secondary users can coexist with primary licensed users and can share the radio spectrum opportunistically. Broadcasting is an important networking primitive that is useful for many CRN applications such as control information dissemination, warning notification, etc. Unfortunately, the spo...