8.1 GENERAL INTRODUCTION

Cell coverage can be based on signal coverage or on traffic coverage. Signal coverage can be predicted by coverage prediction models and is usually applied to a start-up system. The task is to cover the whole area with a minimum number of cell sites. Because 100 percent cell coverage of an area is not possible, the cell sites must be engineered so that the holes are located in the no-traffic locations. The prediction model is a point-to-point model that is discussed in this chapter. We have to examine the service area as occurring in one of the following environments:

• Human-made structures

• In a building area

• In an open area

• In a suburban area

• In an urban area

• Natural terrains

• Over flat terrain

• Over hilly terrain

• Over water

• Through foliage areas

The results generated from the prediction model will differ depending on which service area is used.

There are many field-strength prediction models in the literature. ^{[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28]} They all provide more or less an area-to-area prediction. As long as 68 percent of the predicted values from a model are within 6 to 8 dB (one standard deviation) of their corresponding measured value, the model is considered a good one. However, we cannot use area-to-area prediction models for cellular system design because of the large uncertainty of the...