This project aims at investigating key issues in radio interface design for practical frequency-selective fading channels. It is focused on the new opportunities and challenges that arise when considering broadband radio systems, with an emphasis on packet data transmission. The purpose of such a radio interface is to carry packets to or from wireless users. The destination of packets may be on...

It is well known that the successful operation of cognitive radio (CR) between CR transmitter and CR receiver (CR link) relies on reliable spectrum sensing. To network CRs requires more information from spectrum sensing beyond traditional techniques, executing at CR transmitter and further information regarding the spectrum availability at CR receiver. Redefining the spectrum sensing along with...

The wireless communication serves the efficient information among two or more points wirelessly. Antenna is the main component in the communication, which radiates and receives the radio waves or in broad way. The antenna also plays a role of impedance matching device, which performs the matching of impedances like free-space & transmitter and receiver impedances at receiver end. The antennas c...

A long-term aim of current research into the frequency assignment problem is to identify features that would enable us to classify instances of the problem in terms of certain easily-computed parameters. Although there are good mathematical reasons why this may be impossible in full generality, experimental evidence is emerging which suggests that instances which occur in practice may be amenab...

The situation is complicated by another requirement often found in modern radio designs – to reuse a solution across a range of designs. This means one solution often has to meet the requirements of hand-portables, mobiles and in some case fixed stations. Further, in markets like specialised / professional radio systems or military systems a product can span operating frequencies from 150MHz to...

Several power control methods in cellular radio system are reviewed. Adaptive power control scheme based on the adaptive optimization of transmitter power and receiver filter coefficients is analyzed. The scheme can be mapped to power control algorithm, adaptive receiver digital filter, RAKE receiver power estimator and analog RF power amplifier. The implementation, co-simulation and co-synthes...

A cost effective ZigBee-based wireless parking sensor system is presented in this article. Ultrasonic transmitter and receiver are used for distance measurement. An evaluation, control and wireless data transfer are realized by one chip Panasonic hybrid chip PAN4450 (8-bit microcontroller + IEEE 802.15.4 radio). System consists of four independent distance sensors and one central display and co...

In this paper a 75 pJ/b all-digital quadrature coherent impulse radio ultra-wideband transceiver in 0.18μm CMOS is presented. It consumes 42mW operating at a 560Mbps datarate. The receiver and transmitter share most of the components reducing the area. This design is optimal for low-power low-cost short-range high-speed communications.

Radio frequency impairments such as in-phase/quadrature-phase (IQ) imbalances can result in a severe performance degradation in direct-conversion architecture-based communication systems. In this paper, we consider the case of transmitter and receiver IQ imbalance together with frequency selective channel distortion. The proposed training-based schemes can decouple the compensation of transmitt...

The IEEE802.11a Wireless LAN standard defines a high system performance and therefor requires a certain signal accuracy for the OFDM transmitter output. Taking the potential analog low, medium IF and RF filter imperfections into account it is necessary to pre-equalize the signal stream digitally before transmitting. The paper will concentrate on the description and comparison between different ...