Quadrature modulator and demodulator

 

The proposed quadrature modulator and demodulator, which provide the desired level of performance while minimizing the power consumption. In the quadrature modulator I and Q signals are fed to two pairs of mixers. Each mixer in a pair of mixers modulates the I and Q signal corresponding in-phase or quadrature sinusoidal oscillation of the inverter. I and Q modulated signals from each pair of mixers are summed. The signals from the adders are served by third pair of mixers and modulate the respective inphase and quadrature RF sinusoidal oscillations. The signals from the third pair of mixers are summed and are available as modulated signals. When using this scheme quadrature modulator amplitude balance and the phase error of the modulated signal are insensitive to detuning amplitude and/or phase error of the quadrature splitters used for generating sinusoidal oscillations of the if and RF. In addition, since the first two pairs of mixers and two subsequent adder operate at the intermediate frequency (if), performance requirements (e.g., bandwidth and linearity) of these components can be provided when using the nom the demodulator. The technical result is the creation of a quadrature modulator with improved characteristics. 2 C. and 18 h. p. F.-ly, 3 ill.

Description text in facsimile form (see graphic part)th

Claims

1. Quadrature modulator containing the first quadrature splitter for receiving the first sinusoidal oscillations and the output of the first phase sinusoidal and the first quadrature sinusoidal oscillations, the second quadrature splitter for receiving the second sinusoidal and issuance of the second in-phase sinusoidal and second quadrature sinusoidal oscillations, a first mixer connected to the first quadrature splitter for receiving the first in-phase sinusoidal oscillations, and the first mixer also receives the first information signal and generates the first modulated signal, a second mixer connected to the first quadrature splitter for receiving the first quadrature sinusoidal oscillations, and the second mixer also receives the second information signal and generates a second modulated signal, a third mixer connected to the first Quad is also host to the first information signal and produces a third modulated signal, a fourth mixer coupled to the first quadrature splitter for receiving the first in-phase sinusoidal oscillations, and the fourth mixer also receives the second information signal and generates a fourth modulated signal, the first adder connected to the first and second mixers, a second adder, coupled to the third and fourth mixers for subtracting the output signal of the fourth mixer from the output signal of the third mixer, the fifth mixer coupled to the first adder and the second quadrature splitter, and the fifth mixer takes second in-phase sine wave and produces a fifth modulated signal, the sixth mixer connected to a second adder and a second quadrature splitter, and sixth mixer accepts the second quadrature sine wave and produces a sixth modulated signal and a third adder connected to the fifth and sixth mixers, and a third adder outputs the resulting modulated signal.

2. Quadrature modulator under item 1, characterized in that the first and second information signals contain I and Q (inphase and quadrature) signals, respectively.

3. Quadrature modulate modulator for p. 3, wherein the active devices include MOS transistors.

5. Quadrature modulator under item 3, characterized in that the active devices include bipolar transistors.

6. Quadrature modulator under item 1, characterized in that the quadrature splitters contain environment shifting capacitors.

7. Quadrature modulator under item 1, characterized in that the faucets are made on the elemental multipliers Hilbert.

8. Quadrature modulator under item 7, characterized in that the elemental multipliers Hilbert contain MOS transistors.

9. Quadrature modulator under item 7, characterized in that the elemental multipliers Hilbert contain bipolar transistors.

10. Quadrature modulator under item 7, characterized in that the adders accomplished by cross-connecting the output element of the multipliers Hilbert.

11. Quadrature modulator under item 1, characterized in that the quadrature splitters, mixers and adders performed on the active devices.

12. Quadrature modulator under item 1, characterized in that the quadrature splitters, mixers and adders performed in a specialized IP.

13. Quadrature modulator under item 1, characterized in that the resulting modelerov the RNA modulator for p. 1, characterized in that the resulting modulated signal is modulated quadrature signal manipulation phase shift (CMPS).

15. Quadrature modulator under item 1, characterized in that the resulting modulated signal is a modulated signal is a quadrature amplitude modulation (QAM).

16. Modulator containing the first quadrature splitter for receiving the first sinusoidal and issuance of the second sinusoidal and third sinusoidal oscillations, the second quadrature splitter for receiving the fourth sinusoidal and issuance of the fifth sinusoidal and sixth sinusoidal oscillations, a first mixer connected to the first quadrature splitter for receiving the second sinusoidal, and the first mixer also receives the first information signal and generates the first modulated signal, a second mixer connected to the first quadrature splitter for receiving the third sinusoidal oscillations, and the second mixer also receives the second information signal and generates a second modulated signal, a third mixer, connected to the first quadrature splitter DL the signal and produces a third modulated signal, a fourth mixer coupled to the first quadrature splitter for receiving the second sinusoidal, and the fourth mixer also receives the second information signal and generates a fourth modulated signal, the first adder connected to the first and second mixers, a second adder, coupled to the third and fourth mixers, for subtracting the output signal of the fourth mixer from the output signal of the third mixer, the fifth mixer coupled to the first adder and the second quadrature splitter, and the fifth mixer adopts the fifth sinusoidal oscillation and produces a fifth modulated signal, the sixth mixer connected to a second adder and a second quadrature splitter, and sixth mixer takes the sixth sinusoidal oscillation and produces a sixth modulated signal and a third adder connected to the fifth and sixth mixers, and a third adder outputs the resulting modulated signal.

17. The modulator under item 16, characterized in that the second and third sinusoidal have a phase shift of 90o.

18. The modulator under item 16, characterized in that the fifth and sixth sinusoidal oscillations are phase change is abania selected that the resulting modulated signal is a differential frequency of the first and fourth sinusoidal vibrations.

20. The modulator under item 16, characterized in that the second, third, fifth, and sixth sinusoidal chosen so that the resulting modulated signal is the sum of the frequency of the first and fourth sinusoidal oscillations.

 

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