| 摘要 |
PURPOSE:To perform narrow-band transmission by applying a special process to a sequence of codes. CONSTITUTION:A delta-modulation (DELTAM) output from a signal supply 1, comparator 2, sample pulse supply 3, pulse generator 4 and local demodulator 5 is made into a complement by complementary circuit 7 at intervals of one or several samples. Two outputs of complementary circuit 7 are supplied to selector circuit 9, where a pulse of a narrower band is selected. The DELTAM output after adequate delay process 6, on the other hand, becomes two outputs of complementer 10 in the same way as 7 and change over switch 11 for the outputs is controlled by the output of selector circuit 9 to obtain the output of 10 of a narrower band. Discrimination pulse adder 12 operating at need generates compensation DELTAM output 13 by being supplied with a code indicating the complemented part of the code selected by switch 11. |
