Microwave Communication

1. INTRODUCTION

Microwave communication is a communication system that utilizes the radio frequency band spanning 2 to 60 GHz. As per IIIE, electromagnetic waves between 30 and 300 GHz are called millimeter waves (MMW) instead of microwaves as their wavelengths are about 1 to 10mm. Small capacity systems generally employ the frequencies less than 3 GHz while medium and large capacity systems utilize frequencies ranging from 3 to 15 GHz. Frequencies > 15 GHz are essentially used for short – haul transmission.

Fixed point-to-point microwave systems provide moderate-capacity digital transmission between well-defined locations. The project aims to design a wireless microwave communication system between Batangas State University Main Campus I and Batangas State University Main Campus II using AirFibre antenna technology with point to point line of sight communication. The students need to choose their preferred building for their design. The students must also determine the type of AirFibre antenna to be used, the obstructions and the losses.

1. OBJECTIVES

This study aimed:

1. To develop a point to point microwave communication system design.
2. To made to have a feasible design connecting Batangas State University Main Campus I and Batangas State University Main Campus II using Air Fiber Antenna
3. To satisfy the following needs:

- Feasible design

- Efficient system.

1. To integrate the following parameters in the design of the system:  location site, terrain and obstruction, frequency, Fresnel Zone and height Due to K-curve.

1. MATERIALS AND METHODS

1. Field Survey

1. Map data validation (using Google Earth)

Google Earth is a virtual globe, map and geographical information program that was originally called EarthViewer 3D created by Keyhole, Inc, a Central Intelligence Agency (CIA) funded company acquired by Google in 2004 (see In-Q-Tel). It maps the Earth by the superimposition of images obtained from satellite imagery, aerial photography and geographic information system (GIS) onto a 3D globe.

1. Gathering Field Inputs (Terrain type, tree/obstacle, critical obstruction)

Obstacle, the curvature of the Earth, the geography of the area and reception issues arising from the use of nearby land are important issues to consider when planning and designing the system. In the planning process, it is necessary that “path profiles” are produced in which it provides information about the terrain and Fresnel zones affecting the transmission path.

1. Terrain (elevation)

Terrain, or land relief, is the vertical and horizontal dimension of land surface. Terrain is used as a general term in physical geography, referring to the lay of the land. This is usually expressed in terms of the elevation, slope, and orientation of terrain features. Terrain affects surface water flow and distribution. Over a large area, it can affect weather and climate patterns.

1. Tree/Obstacle

In assessing path clearance, information that is not shown on the terrain must also be considered. In many cases, the heights of trees on top from the terrain profile must also be considered. In many areas, the heights of trees on top from the terrain high points are an obvious source of obstructions.

1. Antenna Specifications[pic 1]

Figure 1. Air Fibre Antenna

        [pic 2]

Figure 2.Antenna Specification

1. RESULTS AND DISCUSSIONS

This part of the study demonstrates the parameters considered with a specific end goal to finish the study and the calculation that will serve as the premise regardless of whether the outline is destined for success.

1. Selected Site

[pic 3]

Figure 3. CABEIHM Building

Figure 3 shows the selected site A for the design which is the CABEIHM Building located at Batangas State University, Main Campus I.

[pic 4]

Fig. 4 CIT Building Old

Figure 4 shows the three storey building located at Batangas State University, Main Campus II