1. ABSTRACT New waveform requirements are pushing the limits of traditional modem design techniques. Fortunately, modern Digital-to-Analog Converter (DAC) and Analog-to-Digital Converter (ADC) can achieve sampling rates in the GHz range. These new DACs and ADCs allow designers to directly synthesize channels that have bandwidths of more than 500 MHz+; allowing either wideband or multi-channel m...

Software-defined radio (SDR), software radio (SWR), and cognitive radio (CR) are futuristic concepts that promise to significantly impact wireless communications technologies. Today, however, technology ironically is one of the limiting factors in the production of a true software radio that is capable of dynamically reconfiguring itself to meet user requirements or spectral limitations. Specif...

Radio spectrum needed for applications such as mobile telephony, digital video broadcasting (DVB), wireless local area networks (WiFi), wireless sensor networks (ZigBee), and internet of things is enormous and continues to grow exponentially. Since spectrum is limited and the current usage can be inefficient, cognitive radio paradigm has emerged to exploit the licensed and/or underutilized spec...

Software Defined Radio is a radio communications transceiver system in which all the typical components of a communication system such as mixers, modulators/demodulators, detectors, amplifiers are implemented through software rather than hardware. This approach is helpful because there is a scope of developing a system which is compatible with more than one mobile communication standard [1]. Th...

This paper gives an overview of the COGEU FP7 project. The main objective of the COGEU project is to design, implement and demonstrate enabling technologies to allow an efficient use of TVWS for mobile radio communications based on secondary spectrum market regime. In particular, COGEU intends to develop innovative mechanisms to realize the concept of TVWS cognitive systems to take advantage of...

In the presentation the most important proprieties of the radio wave propagation in the ionosphere are explained and its impact on the high performance radio transmissions is discussed. The principles of the orthogonal frequency division multiplexing is explained and new digital radio system based on this principle is presented. Then some experimental data registered in Cracow in Poland are sho...

Radio programmes are increasingly available not only from terrestrial networks but also from a large variety of satellite, cable and, indeed, telecommunications networks (e.g. fixed telephone lines, wireless broadband connections and mobile phones). Very often, radio is added to digital television platforms (e.g. DVB-S and DVB-T). Radio receivers are no longer only dedicated hi-fi tuners or por...

This paper describes the implementation of an AM/FM radio receiver in Field Programmable Gate Array (FPGA). Using FPGA as the hardware platform, this approach brings together the flexibility of software and the speed of hardware to build a reconfigurable system, i.e. the behavior of the radio receiver can be changed by simply modifying the software without new hardware. RF modulated signals are...

Air showers from cosmic rays emit short, intense radio pulses. LOFAR is a new radio telescope, that is being built in the Netherlands and Europe. Designed primarily as a radio interferometer, the core of LOFAR will have a high density of radio antennas, which will be extremely well calibrated. This makes LOFAR a unique tool for the study of the radio properties of single air showers. Triggering...

Radio communication systems of the future will require a large increase in user capacity. To achieve this, cell sizes will reduce and the number of base stations will increase. Current base station architectures use analogue combining techniques which are expensive, voluminous and inflexible. This thesis investigates a Digital Signal Processing (DSP) solution which produces a cheaper, smaller a...