Simulation based performance analysis studies for very large (i.e. up to thousands of nodes) Mobile Adhoc NETworks (MANETs) have considered simplistic radio propagation environment (i.e. for urban structures) such as Free Space or Two Ray Ground (TRG) path loss models resulting in over optimistic network performance. This study covers the aspect of scalability with a famous routing approach (i....

Technology makes it easier for us to communicate over a distance. However, there are still many remote areas that find difficult communicate. This is due the fact communication infrastructure in some expensive build while profit will be low. paper proposes combine voice internet protocol (VoIP) mesh network implemented on openWRT router. The routers performing functions. We set up VoIP server r...

The number of customers who use cellular phones indoors is rapidly increasing. In this case, the mobile terminals are basically static and the communication characteristics are wildly different from those seen in outdoor moving use. On the other hand, indoor wireless access systems such as WLAN also become widely used. In static usage, the terminal itself doesn’t move, but the environment aroun...

The modulated scattering array antenna (MSAA) is composed of one normal antenna element and several modulated scattering elements (MSE). In this report, a 2-element MSAA is used as the receiving antenna in a 2 by 2 multiple input multiple output (MIMO) system. The MIMO performance of the MSAA with various array spacing is measured to investigate experimentally the relation between the array spa...

The development of Wi-Fi network is not only about the installment of access point infrastructure, but also related to various factors such as signal strength of the access point, design and infrastructure of the room, distribution of groups of access point users, radio wave interferences, and signal obstacles. Therefore in a Wi-Fi network, the placement of access point has a significant impact...

In this paper, three different frequency reconfigurable multiple-input-multiple output (MIMO) antennas are characterized in terms of their channel capacity performance in an indoor environment. Two 2 × 2 and one 4 × 4 MIMO antenna configurations are investigated. A complete MIMO system is implemented using software defined radio (SDR) platform. The antenna under test can be used at either trans...

The results of statistical analysis of the 60GHz indoor radio propagation channel data collected in 13 different indoor environments are presented. Major outcomes of the analysis are as follows: i) The Root Mean Square (RMS) delay spread values observed range between 3 and 23ns and show a good normal fit. A clear dependence between the rms delay spread values and the transmitter–receiver separa...

In the non-line of sight (NLOS) ultraviolet (UV) scattering communication, the received signals exhibit the characteristics of discrete photoelectrons due to the extremely large path loss. We design and demonstrate an NLOS UV scattering communication system in this work, where the receiver-side signal detection is designed based on a discrete-time Poisson channel model. In our system, a laser a...

Due to the satellite signals are blocked, it is difficult obtain vehicle position in tunnels. We propose a single-site localization scheme for rectangular tunnel environment, where most satellite-based positioning methods can not provide required accuracy. In non-line-of-sight (NLOS) scenarios, we make use of reflection paths as assistants positioning. Specifically, first, virtual stations esta...

Channel models for vehicular networks typically disregard the effect of vehicles as physical obstructions for the wireless signal. We aim to clarify the validity of this simplification by quantifying the impact of obstructions through a series of wireless experiments. Using two cars equipped with Dedicated Short Range Communications (DSRC) hardware designed for vehicular use, we perform experim...