This paper presents an investigation of radio-wave propagation characteristics in the 5 GHz band in a residential two-story house. We investigated the 3-D angular spectra of incident waves when a transmitter and a receiver were set on the first floor and on the second floor, respectively. It was found that the strongest wave arrived at the receiving antenna from the direction of the transmittin...

The antenna range is set up for antenna ratiometry 1 so that two paths are constantly being compared, both originating from a common transmitting antenna. These two paths are called "reference" and "measurement." The reference path uses a fixed antenna that receives what should be a constant level; in reality, there are continuous small fluctuations in received signal at microwave frequencies e...

This paper compares the characteristics in the time-domain of Ultra-wide Bandwidth (UWB) monopole antenna and wide slot antenna. Whether the UWB antenna is suitable for the signal transmitting is not only measured by antenna’s width but also by the characteristics of the time domain. These two antennas are proved to be fit for sending and receiving signals in frequency domain. In this paper, th...

This paper presents an overview of retrodirective antenna systems developed for use in wireless communications. This multiple antenna system automatically reflects incident radiation in the direction of the source radiator by re-transmitting the phase conjugate of the received signal at each antenna. The overall system behaves as a directional antenna with omni-directional coverage and allows t...

We investigate the performance and coexistence techniques for worldwide interoperability for microwave access (WiMAX) delivered from high altitude platforms (HAPs) and terrestrial systems in shared 3.5 GHz frequency bands. The paper shows that it is possible to provide WiMAX services from individual HAP systems. The coexistence performance is evaluated by appropriate choice of parameters, which...

Microstrip patch antennas are strong candidates for use in many wireless communication applications. This paper proposes the use of a patch antenna with U-shaped slot to achieve wideband application with very low return loss. The objective of this paper is to design, construct and fabricate microstrip antennas suitable for Wi-Max application that centred at frequency 5.25GHz. The antenna must o...