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It is possible to formulate a method of obtaining a realistic estimate of thenumber of cells. Let’s define the following items for the purpose of developingan algorithm:Geographic area being considered ¼ A g ðkm 2 Þ.Average radius of a radio cell ¼ r c ðkmÞ.Channel gain (due to dynamic assignment or trunking technique) ¼ z.Cell cluster size ¼ N c .Total bandwidth assigned to the service ¼ Df ch ðHzÞ.Bandwidth allocated to each user ¼ Df u ðHzÞ.For a uniform cell arrangement, the number of cells in a service area may bewritten asn c ¼ A gpr 2 cð8:7aÞfor a circular cells arrangement, as in Fig. 8.8(b). For an arrangement based onany member of the polygon family, the number of cells in any polygonalservice areas can be expressed asn c ¼ A gA pð8:7bÞwhere A p is the generalized area of the polygon (as in Fig. 8.8(a)), where all ofits sides and angles are equal, expressed asA p ¼ nr 2 c tan a=2¼ nar c2¼ 1 4 na2 cot a=2where, using Fig. 8.9 as a guide,a ¼ common length.n ¼ number of sides.a ¼ 360 =n:ð8:7cÞð8:7dÞThe number of radio channels in each cell isn ch ¼ Df chN c Df uð8:8ÞCopyright © 2002 by Marcel Dekker, Inc. All Rights Reserved.