| 摘要 |
PURPOSE:To reduce the cost of parts and to miniaturize a device by constituting a detection means by means of a reference signal generation means generating the reference signal of a specified frequency and a phase detector and constituting a digital delay detection means by means of an orthogonal component guidance means and an operation means detecting a modulation digital signal. CONSTITUTION:The phase detection means 2 consists of the reference signal generation means 20 generating the reference signal of the frequency FL different from the frequency FC of a carrier and a ring demodulator as the phase detector 21 detecting a base band signal from the reference signal and the output of a high frequency amplifier 10. FL is set to be FL=FC+ or -N.FB (FS is the symbol rate of a modulation digital signal) with N as an integer. In the digital delay detection means 3, an A/D converter 30, a pulse oscillator 35 and a delay means 31 constitute the orthogonal component guidance means 36 which A/D-converts the base band signal at the interval of pi/2 as against the phase rotation of the frequency FC-FL. A multiplier 32, an adder 33 and a subtracter 34 constitute the operation means 37 which operates orthogonal component data and subsequent orthogonal component data by one time S slot by the orthogonal component guidance means 36 and which detects the modulation digital signal. |
