The performance of wireless communication systems depends on the radio wave transmission path between the transmitter and the receiver. Unlike wired channels that are stationary and predictable, radio channels are extremely random. In addition, electromagnetic wave propagation characteristics vary significantly over different frequency bands. Therefore it is vital to thoroughly understand the p...

One important application field for wireless sensor networks (WSN) is object localization, thus various realizations yet exist. Here we are just interested in RSSI based localization systems. In particular, we focus on analyzing diverse system parameters, like radio base frequency, transmitting power, or modulation format, to improve the expressiveness of RSSI values. Hence, we built a real-wor...

A novel stochastic channel model for the indoor propagation channel is presented. It is especially for, but not limited to future communication systems with multiple antennas like space division multiple access (SDMA), spatial filtering for interference reduction (SFIR), or multiple-input/multiple-output (MIMO). The model is designed for indoor scenarios, straight forward extendable to urban en...

In this paper, we present the simulation of the propagation characteristics of the picocellular propagation channel environment. The first aim has been to find a correct description of the environment for received wave. The result of the first investigations is that the environment of the indoor wave significantly changes as we change the electric parameters of material constructions. A modifie...

In this paper, we present the simulation of the propagation characteristics of the picocellular propagation channel environment. The first aim has been to find a correct description of the environment for received wave. The result of the first investigations is that the environment of the indoor wave significantly changes as we change the electric parameters of material constructions. A modifie...

This paper will highlight the contributions of Heinrich Hertz by his sensational experiments, carried out in Karlsruhe, Germany, in the years 1885 to 1889, to the first radio communication experiments. Heinrich Hertz developed for the first time a complete pulsed radar, an indoor communication link and a material test set, all in one. The basic system components had been the spark gap oscillato...

Providing high data rates and wide bandwidth applications are the most important challenges that mobile systems and radio networks are trying to accomplish. Radio over Fiber (RoF) system is a promoting research field since it benefits of Passive Optical Network (PON) advantages and unlicensed large bands in 60 GHz millimeter band (57-64GHz). In this study, we consider a complete downlink RoF sy...

Sea clutter is the backscattered returns from a patch of the sea surface illuminated by a radar pulse. The amplitude waveforms of sea clutter and indoor radio propagation are very complicated. Can the apparent randomness of these waveforms be attributed to be generated by low-dimensional chaos? Based on the assumption that a chaotic attractor is characterized by a noninteger fractal dimension a...

The efficient deployment and robust operation of many sensor network applications depend on deploying relays to ensure wireless coverage. Radio mapping aims to predict network coverage based on a small number of link measurements from sampled locations. Radio mapping is particularly challenging in complex indoor environments where walls significantly affect radio signal propagation. This paper ...