Figure 16.2 Frequency reuse patterns a.Reuse factor of 4 b.Reuse factor of 7 16.6
16.6 Figure 16.2 Frequency reuse patterns
Characterizing Frequency Reuse D minimum distance between centers of cells that use the same band of frequencies(called cochannels,.同波道)（相距最近的同频小 区中心间的距离) ■R=radius of a cel d distance between centers of adjacent cells(d R) ■N=number of cells in repetitioust(重复的)pattern ·Reuse factor Each cell in pattern uses unique band of frequencies Hexagonal cell pattern,following values of N possible ·N=2+J2+(1×J),I,J=0,1,2,3,. Possible values of N are 1,3,4,7,9,12,13,16,19,21,. ■Q=D/R=√3N (称为同频复用比例) ■ D/d =N Q的值越小容量越大；Q值大可以提高传播质量，同频干扰小
Characterizing Frequency Reuse D = minimum distance between centers of cells that use the same band of frequencies (called cochannels,同波道)(相距最近的同频小 区中心间的距离) R = radius of a cell d = distance between centers of adjacent cells (d = R) N = number of cells in repetitious(重复的) pattern Reuse factor Each cell in pattern uses unique band of frequencies Hexagonal cell pattern, following values of N possible N = I2 + J2 + (I x J), I, J = 0, 1, 2, 3, . Possible values of N are 1, 3, 4, 7, 9, 12, 13, 16, 19, 21, . Q=D/R= （称为同频复用比例） D/d = Q的值越小容量越大;Q值大可以提高传播质量,同频干扰小 3N N
Frequency circle with radius D Reuse Patterns (a)Frequency reuse pattern for N=4 (b)Frequency reuse pattern for N =7 N=2+J2+0×, 1,J=0,1,2,3,. N: 1,3,4,7,9,12,13, 16,19,21, (c)Black cells indicate a frequency reuse for N =19
Frequency Reuse Patterns N = I2 + J2 + (I × J), I, J = 0, 1, 2, 3, . N: 1, 3, 4, 7, 9, 12, 13, 16, 19, 21,
Frequency Reuse Patterns ■为了找到某一特定 小区相距的同频相 邻小区，按照一下 步骤进行： ■沿着任何一条六边 A 形移动个小区 ■逆时针旋转60度再 移动个小区。 ■图示为 i=3,j=2,N=19
Frequency Reuse Patterns 为了找到某一特定 小区相距的同频相 邻小区，按照一下 步骤进行： 沿着任何一条六边 形移动i个小区 逆时针旋转60度再 移动j个小区。 图示为 i=3,j=2,N=19