This work presents a VSAT based approach for extending mobile communication access to rural communities in developing countries using VSAT and satellite technology. The rural areas are clustered into village community cells with each cluster being served by a non regenerative bidirectional repeater system. The telecommunication technology of choice is the GSM standard. Traffic from the rural ar...

We study the achievable rate region and optimal power allocation for broadcast channels (BC) under orthogonal access schemes. The channel follows a block fading model with channel side information (CSI) perfectly known at the receiver but not at the transmitter. The region boundary is determined by finding the optimal power allocation associated with all boundary points. For the two-user case, ...

This paper introduces the theory of channel modeling for positioning applications in UHF RFID. It explains basic parameters for channel characterization from both the narrowband and wideband point of view. More details are given about ranging and direction finding. Finally, several positioning scenarios are analyzed with channel models developed. All the described models use a degenerate channe...

Objectives: The aim of the present study was to evaluate the relationship between the use of television and behavioral problems in children.  Methods: This is a descriptive and correlational research. The statistical population of the study included 4- to 6-year-old pre-school children in Tehran who were selected using multi-stage cluster sampling. A sample of 150 children was selected. T...

the aim of this paper is to show that modern media are not totally independent of the older media and that there is, specifically, a kind of language transfer from older media such as television to the modern ones. although internet users enjoy relatively more freedom in the virtual reality public domains compared with real public domains, their political communications in negotiation rooms are...

according to reports about 30-thousand people spent watching television had the impact on their memory and recall that the results showed no differences between men and women. the people who watched less than an hour a day did better at every memory function. as these contributors watched negative political ads, physiological responses indicated that their body was reflexively preparing to move...

This paper describes the development of a cognitive radio system through software-defined approach, using universal software peripheral (USRP) devices and digital television equipment for communication in UHF band. The algorithm was developed LabVIEW is based on energy detection, where average power video carrier tv signal calculated compared with established threshold value. As result free cha...