| 摘要 |
The present invention concerns modulation method for transmission of data signals, whereby a first carrier is modulated by the data signals in quadratic way with two sidebands. The RDS-SSB signal with vestigial carrier is produced either by the filter or phase method or it can be generated by synthetic generation and then it is converted by mixing with an oscillator frequency to a long wave band and subsequently transmitted. The arrangement of corresponding circuits is characterized by a RDS coder (2), whose output is connected with a first mixer (3) comprising a first oscillator (4) that is connected by its output side with single-sideband (SSB) filter (5). Its output is connected with a second mixer (6) comprising a second oscillator (7) for conversion to the long wave band. The second mixer (6) output is connected via an output amplifier (8) with input of a long wave transmitter. A receiver for reception of the data signals employs for conversion of a signal received within a long wave band to the single-sideband signal with vestigial carrier an oscillator (15) and a mixing stage (16) to the output of which a bandpass filter (17) is connected, whereby the bandpass filter (17) is connected with a demodulator (18).
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