SU1571790A1 - Device for adaptive demodulation of radio signals of extremely high frequency band - Google Patents

Abstract

The invention relates to radio engineering. The purpose of the invention is to improve noise immunity by predicting the sign and magnitude of the phase dispersion. The device contains an optimum phase value measuring unit (BFSP / 1), multiplier 2, delay line 3, reference oscillator 4, analog signal switch 5, integrator 6 and input signal definition block 7. From the output of BOIZF 1 "0" or "1", the voltage value is fed to the control input of the switch 5, the first signal input of which receives a signal from the input of the device, which is delayed in the delay line 3, and the second signal input of the switch 5 from the driver 4 reference oscillations. From the output of the switch 5, the signal enters the second / reference / input of the multiplier 2, the first / signal / input of which receives the signal from the device input. After multiplying the signal enters the integrator 6, where the process is averaged over the interval (O, T), the signal from the output of the integrator 6 arrives at block 7 to determine the sign of the input signal. 3 il.

Description

ate

TO

DE

The invention relates to radio engineering and can be used in information transmission systems along radio channel tropospheric.

The purpose of the invention is to improve noise immunity by predicting the sign and magnitude of the phase dispersion.

The drawing shows a structural electrical circuit of the proposed device.

The device for adaptive demodulation of radio signals of extremely high frequency range includes an optimum phase measurement unit 1, a multiplier 2, a delay line 3, a reference oscillator 4, analog signal switch 5, an integrator 6, and an input signal character determination unit 7.

The device works as follows.

The input signal is S (t), which can be represented as

S (t) Q (t) l + A (t cos cot + + 4, (t) + tfJ, Q (t)

Where

coefficient characterizing the propagation medium

1 + A (t) - Carrier I envelope

(| (t) is the law of change of the phase of the carrier oscillation; phase angle in the case of transverse reception. From the input, the signal arrives at the input of the optimum phase value measurement unit 1 (BFFS) 1, which is designed so that it quantizes in magnitude and time S ( t) and in the form of a sequence of numbers Uji & t / c, the interval & t is processed, then the input sample is multiplied by the quantized samples of the harmonic reference oscillations sin | cj; lit | and cos o) utj, the result of multiplication as a sequence of numbers {, y; the numbers of the quadrature components of the envelopes x and y are averaged, then the transition from the corners to the polar coordinates is made, the output characterizing the dispersion of the phase uq is immediately at the output of the BFFS 1 selective fading on the propagation path of millimeter radio waves and is equal to 1, if any. From the exit

0

five

0

five

0

five

0

five

Boisph 1 O or 1 (depending on D (), the voltage value is sent to the control input of the switch 5, the first signal input of which receives the signal S (t) from the input of the delay device in line 3 of the delay, to the second signal input of the switch 5 receives a signal from the reference oscillator 4 (FOC) 4, whose input is also the device input. From the output of the switch 5, the signal goes to the second (reference) input of multiplier 2, to the first (signal) input of the multiplier 2 from the device input, the signal S (t) after multiplying From the output of multiplier 2, the signal goes to integrator 6, where the process is averaged over the interval (O, T) from the output of integrator 6, the signal arrives to determine the sign of the input signal to block 7 to determine the sign of the input signal, from the output of which the signal goes for further information processing.

At the same time, in the presence of frequency selective fading in S (t), BIIFF 1 outputs 1, which in the form of voltage goes to the control input of switch 5, which forms the autocorrelation target of signal processing, at which signal S (t) goes to the signal input of the multiplier 2, to the reference input of which, through the switch 5, the signal S (t), delayed per cycle, arrives, after the multiplier 2, the signal is fed sequentially to the integrator 6 and the block 7 of determining the sign of the input signal.

In the absence of frequency selective fading in S (t), BOIFIF 1 outputs O, which in the form of voltage Ue goes to the control input of switch 5, which forms a coherent signal processing circuit, at which signal S (t) goes to signal input multiplier 2, to the reference input of which, via switch 5, a signal arrives taking into account the correction for the change in the dispersion of the fa-. A & S in the carrier recovery scheme from FOC 4, after multiplier 2, the signal is sequentially fed to the integrator 6 and block 7 to determine the sign of the input signal.

The proposed device allows for reliable reception of signals

transmitted over turbulent tropospheric radio channels in the millimeter-wave radio waves, and, therefore, can be used to improve a wide class of radio systems for transmitting information on high-speed digital channels with increased reliability.

Claims (1)

Invention Formula A device for adaptive demodulation of radio signals of an extremely high frequency range of wavelengths, comprising a reference oscillator, the input of which is connected to the input of the delay line and the first input of the multiplier, the output of which is connected to the input of the integrator, the output of which is connected to the input sign five la, the output of which is the output of the device, whose input is the first input of the multiplier, in order to increase the noise immunity by predicting the sign and magnitude of the phase dispersion, an optimum measurement unit for the phase value and an analog signal switch are introduced, the output of which connected to the second input of the multiplier, the first input of which is connected to the input of the optimum phase measurement unit, the output of which is connected to the control input of the analog signal switch, the first signal the input of which is connected to the output of the delay line, while the output of the reference oscillator is connected to the second signal input of the analog signal switch.