| 摘要 |
PROBLEM TO BE SOLVED: To reduce adjusting positions of an SSB(single side band communication) modulation processing circuit and the scale of the circuit. SOLUTION: A modulation signal is digitally converted by an A/D converter 27 and digital output is multiplied by a sine signal and a cosine signal of a reference signal by multiplying parts 41 and 46. Each multiplication output is processed by LPFs 42 and 47, multiplied by a sine signal and a cosine signal of a reference carrier wave signal and balanced modulation is performed to it by the next multiplying parts 43 and 48. Its output is added by an adder part 44, becomes an SSB modulated wave, is converted into an analog signal by a D/A converter 28 and outputted. Thus, the scale of the circuit, the adjusting positions and adjusting time are reduced by digitally processing the SSB modulated output.
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