Page 191 - Intelligent Communication Systems
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I 62     INTELLIGENT COMMUNICATION SYSTEMS
        Using Eq, (37), Eqs. (33) and (34) become Eqs. (38) and (39), respectively.


























        123.4.3 Spectrum Analysis by Means of an Orthogonal Function
        The Walsh function has a value of 1 or -1. It is used for spectrum  analysis of dis-
        crete data. The Walsh function  is composed  of wal(m,n), where w = 0, 1,...,N-1
        and « = 0,1,..., Af-  1. The Walsh function with N= 8 is shown in Figure  12.8. In
        general, the Walsh function  is as follows:













        where  [0  ] is Gaussian and is an integer value of [m/2].
           In Figure  12.8,
           wal(0, ri) is a direct  current
           wal(l, n) wal(3, n) are the base wave
           wal(2, ri) wal(4, ri) are the twofold wave
           wal(7, ri) wal(0, ri) are the quadruple wave
        where m is frequency, which varies between  1 and -1.  m = 1 means that frequency
        is once and m = 2 means  that frequency is twice.
           The two-dimensional  Walsh function  wal(/, k)  is given in Eq.  (43).
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