Twahir Kazema

St. Augustine University of Tanzania (SAUT)

This paper presents a compact sensor system for estimating the dielectric properties of materials based on commercial, off-the-shelf (COTS) modules. The dielectric constant and conductivity of a material under test can be determined from the measurement of the microwave reflected from the material. By using dual microwave sensor modules with a slig...

This work reports the investigation results on how dielectric properties of soil change with fertilizer concentration for catena in Mwanza of Tanzania at 945 MHz frequency band using reflection measurement. Composite soil samples were collected from three catenas: upper, middle, and lower catena sites in Misungwi district located in Mwanza, Tanzani...

Region 2 UHF Frequency band is the frequency range which is used for transmitting Television signals in East Africa. Yagi-uda antenna is an array Antenna designed for various applications, in this paper a 5-element yagi-uda antenna is designed and optimized for operating on the frequency of 500 MHz for digital television signal reception. 4NEC2 and...

A Mathematical Model for Optimizing and simulating the effects of non-identical array element is developed. The analytical and numerical steps on which the Model is based are elaborated in detail in the paper. The observed results of the developed model and methodology used shows that it can be used effectively to Optimize the Linear Array Antenna...

Array antennas offer a wide range of opportunities in the variation of their directivity patterns through amplitude and phase control. Directivity is one of very important parameters when optimizing Antenna. This paper intends to investigate the effects of different geometries of array antenna on directivity and side lobe levels. A six by four ante...

In many wireless networks a single hop is all that is needed or in fact tolerable. The physical region where network is available is known as a coverage area. Generally, a transmitter and a receiver may exchange data by using one or more intermediate relays. In each case a path through the network must be found whereby each hop has a Signal to Int...

In W-LANs a single hop is all that is necessary or in fact acceptable. The region of connectivity around a given source is known as its coverage area. Commonly, a source and a destination may communicate using one or more intermediate relays, in which case a path through the network must be found where each hop has a SINR greater than ß. There are...