RU2012109408A - METHOD FOR DEMODULATION OF PHASE-MODULATED AND FREQUENCY-MODULATED SIGNALS AND DEVICE FOR ITS IMPLEMENTATION - Google Patents

Abstract

1. The method of demodulating phase-modulated and frequency-modulated signals, consisting in the fact that the phase-modulated or frequency-modulated signal is fed to a demodulator made of a four-terminal device, a nonlinear element, a low-pass filter, a separation capacitance, and a low-frequency load, the phase-modulated signal is converted to amplitude-phase-modulated a signal, a frequency-modulated signal is converted into an amplitude-frequency-modulated signal, the conversion of a phase-modulated signal to amplitude-phase the modulated signal and the frequency-modulated signal to the amplitude-frequency-modulated signal is carried out by supplying these signals to the left slope of the frequency response of the demodulator, using a nonlinear element, the spectrum of the amplitude-phase-modulated signal and the amplitude-frequency-modulated signal are destroyed on the high-frequency and low-frequency components, the low-frequency component fed to the integrating low-pass filter circuit; using the low-pass filter, an information low-frequency signal is extracted, the amplitude of which changes according to the law of changing the phase of the phase-modulated input signal or according to the law of changing the frequency of the frequency-modulated signal, using a dividing capacitance, the constant component is eliminated, characterized in that the four-terminal device is made up of a complex of reactive and resistive elements, a nonlinear element is included in the longitudinal circuit between the phase-modulated and frequency-modulated signal and the input of the four-terminal, between the output of the four-terminal and a low-pass filter in the transverse circuit

Claims (2)

1. The method of demodulating phase-modulated and frequency-modulated signals, consisting in the fact that the phase-modulated or frequency-modulated signal is fed to a demodulator made of a four-terminal device, a nonlinear element, a low-pass filter, a separation capacitance, and a low-frequency load, the phase-modulated signal is converted to amplitude-phase-modulated a signal, a frequency-modulated signal is converted into an amplitude-frequency-modulated signal, the conversion of a phase-modulated signal into amplitude-phases the modulated signal and the frequency-modulated signal to the amplitude-frequency-modulated signal is carried out by supplying these signals to the left slope of the frequency response of the demodulator, using a nonlinear element, the spectrum of the amplitude-phase-modulated signal and the amplitude-frequency-modulated signal are destroyed on the high-frequency and low-frequency components, the low-frequency component fed to the integrating low-pass filter circuit; using the low-pass filter, an information low-frequency signal is extracted, the amplitude of which changes according to the law of changing the phase of the phase-modulated input signal or according to the law of changing the frequency of the frequency-modulated signal, using a dividing capacitance, the constant component is eliminated, characterized in that the four-terminal device is made up of a complex of reactive and resistive elements, a nonlinear element is included in the longitudinal circuit between the phase-modulated and frequency-modulated signal and the input of the four-terminal, between the output of the four-terminal and a low-pass filter in the transverse circuit The high-frequency load is obtained, the given dependences of the transfer function module of the high-frequency part of the demodulator on frequency in the interests of forming a given slope of the amplitude-frequency characteristic are provided by selecting the dependence of the element z _{22 of} the complex four-terminal resistance matrix on frequency using the following mathematical expression: $$z_{22}=z_n-\frac{z_{21}^2+z_{21}{D}_{\mathrm{one}}}{E_{\mathrm{one}}+z_{\mathrm{eleven}}}$$

, Where $$D_{\mathrm{one}}=\frac{z_n}{m_{21}\left(\cos {\varphi }_{21}+j\sin {\varphi }_{21}\right)}$$

; E ₁ = z ₀ + z; z ₂₁ , z ₁₁ - the given dependences of the corresponding elements of the resistance matrix of a complex four-terminal network on frequency in a given frequency band; m ₂₁ , φ ₂₁ - the given dependence of the module and phase of the transfer function on frequency in a given frequency band; z is a given dependence of the complex resistance of a bipolar nonlinear element on frequency in a given frequency band; z ₀ , z _n are the given dependences of the complex resistances of the source of the phase-modulated or frequency-modulated signal and the high-frequency load on the frequency in a given frequency band. 2. A device for demodulating phase-modulated and frequency-modulated signals, consisting of a phase-modulated and frequency-modulated signal source, a four-terminal, two-electrode nonlinear element, a low-pass filter, a separation capacitance, and a low-frequency load, characterized in that the four-terminal is made complex in the form of an overlapped T-shaped connection of four complex two-terminal networks, a nonlinear element is included in the longitudinal circuit between the phase-modulated or frequency-modulated source of the signal and the input of the four-terminal, between the output of the four-terminal and the low-pass filter, a high-frequency load is introduced into the transverse circuit, the third two-terminal of the closed T-shaped connection is formed of the first resistive two-terminal with resistance R ₁ connected in series, the first coil with inductance L ₁ and connected in parallel the second resistive two-terminal with resistance R ₂ and the second coil with inductance L ₂ , the values of the parameters of the third two-terminal T-shaped connection defined in accordance with the following mathematical expressions: $$R_{\mathrm{one}}=\frac{(r_{\mathrm{one}}-r_2)({\omega }_2^2{r}_{\mathrm{one}}-{\omega }_{\mathrm{one}}^2{r}_2)+{({\omega }_2{x}_{\mathrm{one}}-{\omega }_{\mathrm{one}}{x}_2)}^2}{(r_r-r_2)({\omega }_2^2-{\omega }_{\mathrm{one}}^2)};$$

$$L_{\mathrm{one}}=\frac{x_{\mathrm{one}}{x}_2({\omega }_{\mathrm{one}}^2+{\omega }_2^2)-{\omega }_{\mathrm{one}}{\omega }_2[{(r_{\mathrm{one}}-r_2)}^2+x_{\mathrm{one}}^2+x_2^2]}{({\omega }_{\mathrm{one}}^2-{\omega }_2^2)({\omega }_{\mathrm{one}}{x}_2-{\omega }_2{x}_{\mathrm{one}})};$$

$$R_2=\frac{{(x_2{\omega }_{\mathrm{one}}-x_{\mathrm{one}}{\omega }_2)}^{\mathrm{four}}+{(r_2-r_{\mathrm{one}})}^2({\omega }_{\mathrm{one}}{}^2+{\omega }_2^2){(x_2{\omega }_{\mathrm{one}}-x_{\mathrm{one}}{\omega }_2)}^2+{(r_2-r_{\mathrm{one}})}^{\mathrm{four}}{\omega }_{\mathrm{one}}^2{\omega }_2^2}{(r_2-r_{\mathrm{one}})({\omega }_2^2-{\omega }_{\mathrm{one}}^2){(x_2{\omega }_{\mathrm{one}}-x_{\mathrm{one}}{\omega }_2)}^2};$$

$$L_2=\frac{{(x_2{\omega }_{\mathrm{one}}-x_{\mathrm{one}}{\omega }_2)}^{\mathrm{four}}+{(r_2-r_{\mathrm{one}})}^2({\omega }_{\mathrm{one}}{}^2+{\omega }_2^2){(x_2{\omega }_{\mathrm{one}}-x_{\mathrm{one}}{\omega }_2)}^2+{(r_2-r_{\mathrm{one}})}^{\mathrm{four}}{\omega }_{\mathrm{one}}^2{\omega }_2^2}{(r_2-r_{\mathrm{one}})({\omega }_{\mathrm{one}}^2-{\omega }_2^2)(x_2{\omega }_{\mathrm{one}}-x_{\mathrm{one}}{\omega }_2){\omega }_{\mathrm{one}}{\omega }_2}$$

, where r ₁ , r ₂ , x ₁ , x ₂ are the optimal values of the real and imaginary components of the resistance of the third complex two-terminal complex four-terminal at two frequencies; $$Z_{3n}=r_n+j{x}_n=\frac{(Z_{\mathrm{one}n}+Z_{\mathrm{four}n})[Z_{2n}(D_{\mathrm{one}}-E_{\mathrm{one}}-z_{nn})-E_{\mathrm{one}}{z}_{nn}]-Z_{\mathrm{one}}{Z}_{\mathrm{four}n}(Z_{2n}+z_{nn})}{E_{\mathrm{one}}(Z_{\mathrm{four}n}+z_{nn})+(Z_{\mathrm{one}n}+Z_{2n})(z_{nn}-D_{\mathrm{one}}+Z_{\mathrm{four}n}+E_{\mathrm{one}})}$$

- the optimal values of the complex resistance of the third complex two-terminal overlapped T-shaped connection at two frequencies; $$D_{\mathrm{one}}=\frac{z_{nn}}{m_{21n}(\cos {\varphi }_{21n}+j\sin {\varphi }_{21n})}$$

; E ₁ = z _0n + z _n ; Z _1n , Z _2n , Z _4n are the set values of the complex resistance of the first, second and fourth complex two-terminal devices of an overlapped T-shaped connection at two frequencies; m _21n , φ _21n - given values of the modules and phases of the transfer function of the high-frequency part of the demodulator at two frequencies; z _n - set values of the complex resistance of a bipolar nonlinear element at two frequencies; z _0n , z _nn are the set values of the complex resistances of the source of the phase-modulated or frequency-modulated signal and the high-frequency load at two frequencies; ω _1,2 = 2πf _1,2 ; n = 1,2 - numbers of the given two frequencies f _1,2 .