| 摘要 |
If frequency-modulated stereo sound broadcast signals are intended to be transmitted via a transmission system of the third PCM hierarchy, an additional word (Z) must be inserted as a sync word in the (parallel) input data stream (Dn in Fig. 2) produced by digitisation in each case after n = 63 words (W) each comprising m = 8 bits, in order to construct the required frame (R(n+1)) of the transmission system. The input data stream (Dn) with the clock at frequency (fn)/m = (33.831)/8 MHz is sampled with a first clock (T1) at frequency f(1(n+1))/m = (34.368)/8 MHz, the first clock (T1) in each case having a phase shift of one half-period duration in each case between the 32nd and 33rd word and between the 63rd and the subsequent 1st word. The first data stream (D1) produced in this way is sampled with a second clock (T2) at frequency (34.368)/8 MHz, the second clock (T2) having a phase shift of one period length in each case between the 63rd and the subsequent 1st word (corresponding to the suppression of the respective 64th clock pulse). In the second data stream (D2) produced by this sampling, the 63rd words are of double length, so that the additional word (Z) can be inserted in the second half of these 63rd words as the 0th word of the subsequent frame (R(n+1)). By additionally delaying the clocks (T1, T2) by one half or one whole period duration in relation to the clock of the input data stream (Dn), ... Original abstract incomplete. <IMAGE>
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