Ad hoc network is a collection of wireless mobile nodes that dynamically form a temporary network without the use of any existing network infrastructure or centralized administration. A cognitive radio is a radio that can change its transmitter parameters based on interaction with the environment in which it operates. The basic idea of cognitive radio networks is that the unlicensed devices (co...

In 2003, a method of measurement for radiated RF power and receiver performance was proposed by CTIA. In the certification [1], it is recommended that radiation characteristics in real operative state should be evaluated. Although maximal EIRP has been used to obtain radiated power of radio equipments, it cannot always indicate their performance in real operative state. Therefore, CTIA certific...

In this paper we extend the analysis of tworeceiver broadcast channels with random parameters to the three-receivers case. Specifically we base our work on Nair and El Gamal’s results for the three-receiver discrete memoryless multilevel broadcast channel and assume that state information is available non-causally at the transmitter. We provide an achievable rate region for this setting and ack...

In this paper a novel radio-interferometric object trajectory estimation method is proposed, which can be used to track moving objects. The system utilizes a low number of fixed infrastructure nodes equipped with radio transceivers, and the tracked object also carries a simple transceiver. Selected transmitter infrastructure nodes produce interference signals at the fixed infrastructure receive...

We have developed a miniaturized very high frequency (VHF) transmitter design for radio-tagging small animals. The average mass of the circuitry is 0.084 g (range 0.081-0.087), hence, with the smallest power cell, complete tags weigh 0.2 g and have a life of 18-22 days. We further demonstrate that with such small tags the technique of attaching the device to the animal's body strongly affects t...

The present paper analyzes radio signal propagation in long tunnels with different cross sectional size and shape at various signal carrier frequencies, transmitter/receiver positions and material properties applying computer simulations. The influences of different parameters were investigated and results were compared to the empirical four-slope path loss model for long tunnels. It was shown ...

The primary goal of this project was educational: to demonstrate Software Defined Radio based prototyping using Visual C++ Express and Code Composer Studio. More specifically an IEEE802.11a Phy [1] compliant baseband processor was written in C++ and a radio link demonstrated “live” using a standard PCand the DSK6713 kit from Spectrum Digital [2] for baseband processing at the receiver and trans...

In this paper, a very low power and low complexity all digital impulse radio ultra wideband (IR-UWB) transmitter is presented. The pulse repeating frequency (PRF) of the transmitted signal is controlled digitally, which complies with federal commission committee (FCC) regulations. In order to control the transmitted power the amplitude of transmitted signals is reduced by increasing the PRF. Th...