| 摘要 |
In cases where exacting requirements with regard to immunity to interference are imposed on signals transmitted via radio, so-called burst mode is commonly used, often in conjunction with a frequency-hopping method. A preamble in the form of a shift-proof code word (CW) is placed in front of the error-protected information in formatted form. In order to achieve fast synchronisation of the bit and frame phase at the receiving end with the aid of the preamble, it is proposed to sample each bit (bit1, bit2...) of the incoming signal n times continuously, in each case to form the consecutive signal sample values relating to a specific bit phase (1, 2, ... 8) into signal sample sequences (sq1, sq2...sqx, sqy...sqn, sq(n+1)...sq(n+9)) corresponding in number to the number of preamble bits, to compare the order of these signal sample sequences with the preamble permanently stored at the receiving end for correspondence and to define the correct bit and frame phase depending on the results of the comparison. <IMAGE>
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