Digital signals demodulator with quadrature amplitude manipulation

FIELD: radio engineering, communication.

SUBSTANCE: digital signals demodulator with quadrature amplitude manipulation includes the analog-to-digital converter, multiple-bit codes shift register at four readings, the first and the second n-cascade channels of quadrature signals processing, the first and the second threshold devices, critical device, decoding device, and normalizing and synchronizing device.

EFFECT: provision of high-speed digital demodulation of signals with quadrature amplitude manipulation and eliminating of the amplitude nonidentity of quadrature demodulator channels.

8 dwg

 



 

Same patents:

FIELD: radio engineering, communication.

SUBSTANCE: present invention relates to transmission and reception of animated image data. The receiver includes a demodulation circuit configured to demodulate data and control information attached to the data, and an extraction circuit configured to extract part of the control information, wherein the demodulation circuit is configured to perform demodulation in accordance with the extracted part of control information.

EFFECT: reduced size of the register storing control information.

11 cl, 10 dwg

FIELD: radio engineering, communication.

SUBSTANCE: radio station further includes a data transmission channel converter, a data reception channel converter, a data transmission channel information converter, wherein the data transmission channel converter has six channel data transmission packet generators. The data transmission channel information converter has six channel data transmission channel information generators. Use of the device allows operation of the radio station in duplex mode at one frequency on one antenna with ten telephone channels and switching six channels from the fifth to the tenth channel for operation in data transmission mode with speeds in channel of: 100, 300, 500 and 1200 Bd for operation with data terminal equipment and at 1200 Bd for operation with a personal computer.

EFFECT: high flexibility during communication by introducing data transmission channels, increasing throughput of the radio station.

12 cl, 15 dwg

FIELD: information technologies.

SUBSTANCE: accuracy of assessments of disturbance of a phase balance between inphase (I) and quadrature (Q) components may be increased by means of their completion on a transmitter and a receiver, which are connected via a local feedback connection, and removal of radio noise of mutual spectrum in transmitted packets. As soon as these accurate disturbances of the I/Q phase balance have been determined, they may be used to correct a signal processed by a transmitter or a receiver, in order to increase efficiency and throughput capacity of communication means using this signal.

EFFECT: accurate measurement and assessment of balance disturbances between inphase and quadrature components of a complex group signal.

39 cl, 5 dwg

FIELD: information technology.

SUBSTANCE: reception device has apparatus for determining the first, second and third position of the initial position of the fast Fourier transform (FFT) interval, apparatus for selecting one of the determined initial positions of the FFT interval, FFT apparatus for performing fast Fourier transformation of an orthogonal frequency division multiplexing (OFDM) signal in the time domain by using the initial position selected by the selection apparatus in order to generate a first OFDM signal in the frequency domain. The apparatus for determining the first position calculates the value of correlation between the OFDM signal in the time domain and the signal obtained by delaying said time-domain OFDM signal by the length of the effective symbol. Apparatus for determining the second position estimates the channel characteristic for transmitting the OFDM signal and the delay profile before estimating the value of interference between symbols with respect to each of the FFT intervals. The apparatus for determining the third position establishes the FFT interval with offset from the FFT interval used for generating the first OFDM signal, for generating the second OFDM signal before eliminating distortions from the first and second OFDM signals in order to generate an adjusted signal.

EFFECT: reducing multiple-beam interference by adjusting the symbol synchronisation signal.

8 cl, 26 dwg

FIELD: information technology.

SUBSTANCE: hard-decision bit from bits indicating the P-axial coordinate of a reception signal point is input into an area detection circuit, and based on the hard-decision bit input, the area detection circuit detects and outputs an area on the phase plane where the coordinate of the reception signal point is present. A soft-decision bit from bits indicating the coordinate of the reception signal point is input into a log-likelihood ratio (LLR) circuit, and based on the soft-decision bit input, the LLR circuit calculates a primary LLR. A LLR converter calculates the final LLR based on an output signal (area detection result) from the area detection circuit. In such a configuration, a log-likelihood ratio is calculated while limiting the scope within which the value of the log-likelihood ratio varies according to the position of the reception signal point, the interval between adjacent signal points including the hard-decision threshold of the bit.

EFFECT: log-likelihood ratio calculation at a higher rate while reducing the size of the circuit and consumed power, independent of the multilevel number of the modulation method.

22 cl, 17 dwg

FIELD: information technology.

SUBSTANCE: apparatus for transmitting data comprises an encoder for encoding data, a multiplexer for multiplexing the encoded data and a training sequence code (TSC), a modulator for modulating the multiplexed data using a defined modulation scheme and a transmitter for transmitting the modulated data. The modulator modulates TSC based on two constellation points having the highest absolute value and opposite signs among M constellation points in the constellation according to the defined modulation scheme.

EFFECT: high efficiency of transmitting and receiving data using a training sequence code.

20 cl, 17 dwg

FIELD: information technology.

SUBSTANCE: first evaluation of the wireless channel is obtained during restoration of a variety of parallel data streams on the basis of received pilot symbols. Detection is carried out for the received data symbols using the first channel evaluation to obtain detected symbols for the first data stream. Obtained detected symbols are decoded to receive the decoded first stream of data that are encoded again for obtaining repeatedly modulated symbols. The second channel evaluation is obtained on the basis of the repeatedly modulated symbols. The first and the second channel evaluations are joined together to obtain the third channel evaluation having the higher quality. The interfering signal determined by the first data stream is evaluated and removed using the third channel evaluation. Detection of symbols is carried out when removing the evaluated interference from the main stream using the third channel evaluation to obtain detected symbols for the second data stream. Obtained detected symbols are additionally decoded to receive the decoded data of the second data stream.

EFFECT: high-quality channel evaluation.

37 cl, 7 dwg

FIELD: radio communications, possible use in demodulators of radio-relay communication systems which use signals with quadrature amplitude manipulation.

SUBSTANCE: in accordance to the invention, error signal is generated every time when on two adjacent clock intervals change of modulating symbol value occurs, not only when sign change occurs. Device contains serially connected solving device (1), adder (4), second input of which is connected to output of solving device (1) through serially connected sign inverter (3) and first delay block (2), and multiplier (6), and also second delay block (5), connected to second input of device. Introduced are serially connected second adder (7), first input of which is connected to output of delay block (2), second input - to output of sign inverter (3), divider by two (8), and third adder (9), second input of which is connected to output of delay block (5), and its output - to second input of multiplier (6). Solving device (1) makes a decision about value of modulating symbol being receipt, and not about its sign.

EFFECT: increased interference resistance of device.

2 cl, 15 dwg, 1 tbl

FIELD: radio communications and radio communication systems.

SUBSTANCE: proposed demodulator that incorporates provision for receiving amplitude-modulated telephone data and transmitting frequency-telegraphy data over single radio communication channel at a time is provided with newly introduced demodulator channel for amplitude-modulated signal adder that enables compensation for noise occurring in demodulator due to frequency-telegraphy signal in received signal, channel organized to evaluate amplitude of frequency-telegraphy signal wherein noise resulting from amplitude-modulated signal in signal being received is compensated for, as well as channel separating useful information from frequency-telegraphy signal.

EFFECT: enlarged functional capabilities.

1 cl, 1 dwg

FIELD: communications.

SUBSTANCE: demodulation device for 64-based quadrature amplitude modulation for receipt of input signal, which contains k-numbered quadrature signal and k-numbered common-mode signal, which contains first and second soft solution generators, which are made with possible generation of soft solution values on basis of given equations.

EFFECT: higher efficiency.

3 cl, 6 dwg

FIELD: radio engineering; demodulating sixteen-position quadrature-amplitude keyed signals.

SUBSTANCE: proposed demodulator, type KAM-16, has three phase detectors, two solvers, two four-position modulators, three subtracters, adder, amplifier, two multipliers, two limiters, low-pass filter, voltage-controlled generator, and four EXCLUSIVE OR gates. Amplitude difference of demodulator quadrature subchannels is detected and eliminated by subjecting signal to following procedures. Demodulator input signal is decomposed by means of recovered carrier signal into cophasal and quadrature components which are passed through first and second controlled amplifiers, supplied to solver, and tetrad of demodulated characters (A, B, C, D) is obtained at demodulator output. Four-position phase keyed signal is obtained across output of first four-position modulator by means of recovered carrier signal and two digital characters (C, D) out of tetrad of demodulated characters (A, B, C, D).

EFFECT: enhanced noise immunity.

1 cl, 5 dwg

FIELD: communications.

SUBSTANCE: demodulation device for 64-based quadrature amplitude modulation for receipt of input signal, which contains k-numbered quadrature signal and k-numbered common-mode signal, which contains first and second soft solution generators, which are made with possible generation of soft solution values on basis of given equations.

EFFECT: higher efficiency.

3 cl, 6 dwg

FIELD: radio communications and radio communication systems.

SUBSTANCE: proposed demodulator that incorporates provision for receiving amplitude-modulated telephone data and transmitting frequency-telegraphy data over single radio communication channel at a time is provided with newly introduced demodulator channel for amplitude-modulated signal adder that enables compensation for noise occurring in demodulator due to frequency-telegraphy signal in received signal, channel organized to evaluate amplitude of frequency-telegraphy signal wherein noise resulting from amplitude-modulated signal in signal being received is compensated for, as well as channel separating useful information from frequency-telegraphy signal.

EFFECT: enlarged functional capabilities.

1 cl, 1 dwg

FIELD: radio communications, possible use in demodulators of radio-relay communication systems which use signals with quadrature amplitude manipulation.

SUBSTANCE: in accordance to the invention, error signal is generated every time when on two adjacent clock intervals change of modulating symbol value occurs, not only when sign change occurs. Device contains serially connected solving device (1), adder (4), second input of which is connected to output of solving device (1) through serially connected sign inverter (3) and first delay block (2), and multiplier (6), and also second delay block (5), connected to second input of device. Introduced are serially connected second adder (7), first input of which is connected to output of delay block (2), second input - to output of sign inverter (3), divider by two (8), and third adder (9), second input of which is connected to output of delay block (5), and its output - to second input of multiplier (6). Solving device (1) makes a decision about value of modulating symbol being receipt, and not about its sign.

EFFECT: increased interference resistance of device.

2 cl, 15 dwg, 1 tbl

FIELD: information technology.

SUBSTANCE: first evaluation of the wireless channel is obtained during restoration of a variety of parallel data streams on the basis of received pilot symbols. Detection is carried out for the received data symbols using the first channel evaluation to obtain detected symbols for the first data stream. Obtained detected symbols are decoded to receive the decoded first stream of data that are encoded again for obtaining repeatedly modulated symbols. The second channel evaluation is obtained on the basis of the repeatedly modulated symbols. The first and the second channel evaluations are joined together to obtain the third channel evaluation having the higher quality. The interfering signal determined by the first data stream is evaluated and removed using the third channel evaluation. Detection of symbols is carried out when removing the evaluated interference from the main stream using the third channel evaluation to obtain detected symbols for the second data stream. Obtained detected symbols are additionally decoded to receive the decoded data of the second data stream.

EFFECT: high-quality channel evaluation.

37 cl, 7 dwg

FIELD: information technology.

SUBSTANCE: apparatus for transmitting data comprises an encoder for encoding data, a multiplexer for multiplexing the encoded data and a training sequence code (TSC), a modulator for modulating the multiplexed data using a defined modulation scheme and a transmitter for transmitting the modulated data. The modulator modulates TSC based on two constellation points having the highest absolute value and opposite signs among M constellation points in the constellation according to the defined modulation scheme.

EFFECT: high efficiency of transmitting and receiving data using a training sequence code.

20 cl, 17 dwg

FIELD: information technology.

SUBSTANCE: hard-decision bit from bits indicating the P-axial coordinate of a reception signal point is input into an area detection circuit, and based on the hard-decision bit input, the area detection circuit detects and outputs an area on the phase plane where the coordinate of the reception signal point is present. A soft-decision bit from bits indicating the coordinate of the reception signal point is input into a log-likelihood ratio (LLR) circuit, and based on the soft-decision bit input, the LLR circuit calculates a primary LLR. A LLR converter calculates the final LLR based on an output signal (area detection result) from the area detection circuit. In such a configuration, a log-likelihood ratio is calculated while limiting the scope within which the value of the log-likelihood ratio varies according to the position of the reception signal point, the interval between adjacent signal points including the hard-decision threshold of the bit.

EFFECT: log-likelihood ratio calculation at a higher rate while reducing the size of the circuit and consumed power, independent of the multilevel number of the modulation method.

22 cl, 17 dwg

FIELD: information technology.

SUBSTANCE: reception device has apparatus for determining the first, second and third position of the initial position of the fast Fourier transform (FFT) interval, apparatus for selecting one of the determined initial positions of the FFT interval, FFT apparatus for performing fast Fourier transformation of an orthogonal frequency division multiplexing (OFDM) signal in the time domain by using the initial position selected by the selection apparatus in order to generate a first OFDM signal in the frequency domain. The apparatus for determining the first position calculates the value of correlation between the OFDM signal in the time domain and the signal obtained by delaying said time-domain OFDM signal by the length of the effective symbol. Apparatus for determining the second position estimates the channel characteristic for transmitting the OFDM signal and the delay profile before estimating the value of interference between symbols with respect to each of the FFT intervals. The apparatus for determining the third position establishes the FFT interval with offset from the FFT interval used for generating the first OFDM signal, for generating the second OFDM signal before eliminating distortions from the first and second OFDM signals in order to generate an adjusted signal.

EFFECT: reducing multiple-beam interference by adjusting the symbol synchronisation signal.

8 cl, 26 dwg

FIELD: information technologies.

SUBSTANCE: accuracy of assessments of disturbance of a phase balance between inphase (I) and quadrature (Q) components may be increased by means of their completion on a transmitter and a receiver, which are connected via a local feedback connection, and removal of radio noise of mutual spectrum in transmitted packets. As soon as these accurate disturbances of the I/Q phase balance have been determined, they may be used to correct a signal processed by a transmitter or a receiver, in order to increase efficiency and throughput capacity of communication means using this signal.

EFFECT: accurate measurement and assessment of balance disturbances between inphase and quadrature components of a complex group signal.

39 cl, 5 dwg

FIELD: radio engineering, communication.

SUBSTANCE: radio station further includes a data transmission channel converter, a data reception channel converter, a data transmission channel information converter, wherein the data transmission channel converter has six channel data transmission packet generators. The data transmission channel information converter has six channel data transmission channel information generators. Use of the device allows operation of the radio station in duplex mode at one frequency on one antenna with ten telephone channels and switching six channels from the fifth to the tenth channel for operation in data transmission mode with speeds in channel of: 100, 300, 500 and 1200 Bd for operation with data terminal equipment and at 1200 Bd for operation with a personal computer.

EFFECT: high flexibility during communication by introducing data transmission channels, increasing throughput of the radio station.

12 cl, 15 dwg

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