RU116292U1 - RADIO RECEIVER OF HIGH SPEED INFORMATION OF SPACE RADIO LINE - Google Patents

Abstract

1. A device for receiving high-speed information of a space radio link, containing a band-pass filter (PF), a matched filter (SF), a balanced modulator (BM), a demodulator (DM), the first and second block decoders (DC), an information receiver (PI), a reception chopper signal unit (PBS), a parasitic signal displacement calculator (VPS), a digital signal displacement compensation device (DCC), a symbolic decision unit (RBS), a memory unit (MAM) of the receiver signal samples, the first and second transducer, while the bandpass filter input ( PF) is the input of the device, bandpass filter (PF), matched filter (SF), balanced modulator (BM), demodulator (DM), first converter, first block decoder (DC), information receiver (PI) are connected in series, respectively, the second output the demodulator (DM) is connected to the input of the memory unit (MAM) of the receiver signal samples, the second output of the first block decoder (DC) is connected to the input of the signal block reception interruptor (PBS), the cat output orgo is connected to the first inputs of a parasitic signal displacement calculator (VPS) and a digital signal displacement compensation device (DCC), the DCC output is connected to the second input of the DCC, the PAM output of the receiver's signal samples is connected to the second input of the IPC and to the third signal input of the DCC, the DCC output is connected with the input of the symbolic decision block (RBS), the output of which is connected to the input of the second breaker, the output of the second breaker is connected to the input of the second block decoder (DC), the signal output of which is connected to the second input of the information receiver (PI). ! 2. A device according to claim 1, wherein the first and second transformers comprise a transform operator�

Description

The utility model relates to radio engineering and can be used in radio systems with a phase modulation method, when high-speed reception occurs with the Doppler effect in a space radio link.

It is known that the Doppler effect makes it difficult to receive information on the radio link.

The prior art scheme of digital information radio reception [1], in which the carrier enters into communication and monitors the carrier frequency, synchronizes the reception of blocks and bits of information, filters the received signals, decodes information blocks by noise-free decoding, where the spurious is determined and compensated the displacement of the constant component of the signal from the Doppler effect and noise interference. The block diagram of figure 1, makes the connection to the carrier frequency and monitors the carrier frequency, synchronizes the reception of blocks and bits of information, amplifies and records the received signal of the binary number system, performs demodulation of the phase modulation (FM) signal, filters the received signal from interference , decodes information blocks by noise-correcting decoding.

The reception of information is block, KIM-FM is used. An example of a radio reception device providing for communication and synchronization of information reception [2, p.203-215, 237]. Entering into communication is performed in a communication session when information is not received.

The circuit contains a bandpass filter (PF), a matched filter (SF), a balanced modulator (BM), a demodulator (DM), block decoders (DC), an information receiver (PI), a signal block receiving chopper (PPBS), a signal stray signal calculator ( UPU), a digital signal offset compensation device (CCU), a decisive symbol block (RBS), a memory block (PAM) of the receiver's signal reports. PF, SF, BM, DM, DK solve the problem of receiving information in real time. Upon detection of a error number that is more than acceptable by the DC, the digital samples of the signal are entered in the MAM of the recipient signal reports, the IPS and the CCM determine the phase signal offset and compensate for stray phase displacements in the signal samples. The second decoder DC performs noise-correcting decoding of the corrected block of information and transmits the information to the consumer.

At the modern technical level, KIM-FM is used for signal reception, the message uses the independence of the characters “0”, “1” and the same a priori probability of occurrence of zero and one [2, p .97].

In blocks of numbers from the method of the applied binary system, a series of characters of different lengths are formed and the probability of occurrence of zero and one is not equal. Approaching the independent reception of the characters “0”, “1” in a message is achieved by modulating the message with a code sequence of chopping series (CPIS) for transmission at the radio frequency, this includes modulation with a pseudo-noise signal (PSN), the use of randomization and special modulation formats. In demodulation, CPIS is used. In the reception scheme with CPIS, positive results are achieved when the information of the received signal from the use of CPIS is not distorted.

The CCDS technical recommendation allows modulation formats that can use six bit representation formats, three NRZ formats, and three non return-to-zero Biφ (phase) formats. Modulation forms use differential coding. In the latest formats, the duration of each bit of information is halved.

It is known to use coding to reduce the likelihood of disruption of bit synchronization of a stream of units (zeros) of a long series — adding a message of bits of a phase-modulated signal modulo two with a stream of bits of the meander structure [3, p. 240]. This recommendation is applied in Biφ format.

It is known that the transmitted signals contain a discrete and continuous part of the spectrum, which gives a specific interference in the passband of the synchronization channel. No matter how narrow the bandwidth of the synchronization channel, part of the power from the continuous spectrum necessarily falls into it. The formation of long series leads to an increase in the power spectral density near the frequency ω ₀ ; additional fluctuations of the phase of the reference voltage arise, leading to a failure of synchronization. Modulations FM-FM or KIM-FM-FM, making the continuous part of the spectrum not adjacent to the carrier frequency ω ₀ exclude the occurrence of additional noise in the channel [3, p.234].

A disadvantage of the known device is that long series of messages give spectral components in the low frequency region, leading to a failure of synchronization.

Another disadvantage of the reception scheme is that the use of the CPIS for the received signal increases the number of spectral components in the high-frequency region, which increases the distortion due to the effect of the Doppler effect and the ionosphere. The parasitic shift of the spectral components entails fading and distortion of the phase signal. Fading areas depend on the communication range, there are areas of slight fading, where distortion of the signal from the CPIS is not observed, and areas of fading of the signal, where the ratio P _C / P _W decreases and reaches a threshold value. Pictures of fading and distortion are built by a computer in the Delphi 3 Standart system in figure 2, figure 3. In the construction of vector diagrams of the signals of Fig.4 - Fig.8. complex signals were used [4, p. 27, 31]. Fading with the oscillation components of the upper side frequency band ω ₀ + Ω = f _B and the lower side frequency band ω ₀ -Ω = f _{H is} illustrated by the vector diagram of FIG. 5, FIG. 6. Fading results from a divergence of side frequencies and a phase shift as a result of the Doppler effect. Vector diagrams, Fig.7, Fig.8. show the discrepancy causing a change in waveform. Strong distortions arise from the discrepancy and spurious phase shift of frequencies of the order of π. The signal distortion from the Doppler effect is deterministic, the amount of distortion depends on the reception range S, or the propagation time of the signal before reception. Modulation of the CPIS, a chopping series of characters, leads to an increase in fading and distortion of the signal, which primarily occurs on the high-frequency components of the spectrum. A decrease in the amplitude of the signal from fading reduces the ratio P _C / P _W. The difference between the distorted input and undistorted heterodyne signals forms an interference that worsens the ratio P _C / P _W.

The technical result of the claimed radio reception device for high-speed information of a space radio link is to reduce the loss and distortion of the signal from the Doppler effect during bit-by-bit transmission of digital information in the radio link in the number system 256.

The technical result is achieved by the fact that the radio reception device for high-speed information of a space radio link containing a bandpass filter (PF), a matched filter (SF), a balanced modulator (BM), a demodulator (DM), the first and second block decoders (DK), the receiver of information (PI ), a signal block receiving chopper (PBS), a signal stray signal calculator (SPS), a digital signal bias compensation device (CCU), a symbol decider (RBS), a memory block (PAM) of the receiver signal samples, the first and second converter, p In this case, the input of the band-pass filter (PF) is the input of the device, the band-pass filter (PF), matched filter (SF), balanced modulator (BM), demodulator (DM), the first converter, the first block decoder (DC), the receiver of information (PI) connected in series, respectively, the second output of the demodulator (DM) is connected to the input of the memory block (PAM) of the samples of the recipient signal, the second output of the first decoder block (DC) is connected to the input of the chopper of the reception of the signal block (PPBS), the output of which is connected to the first inputs of the stray cm calculator signal amplification (IPN) and a digital signal offset compensation device (CCU), the IPN output is connected to the second input of the CAM, the SAM output of the receiver signal is connected to the second input of the IPC and to the signal third input of the CMS, the output of the CAM is connected to the input of the decimal symbol block ), the output of which is connected to the input of the second chopper, the output of the second chopper is connected to the input of the second block decoder (DC), the signal output of which is connected to the second input of the recipient of information (PI).

The first and second converters contain a number conversion operator (HRE), which translates the number of the number system 256 into the number of the binary number system.

The first and second converters contain the number conversion operator (HRE) of the number system 256, which translates the number of the number system 256 into the number of the binary number system by removing the octets that separate the digits of the number of the number system 256.

The features and essence of the utility model are explained in the detailed description illustrated by the drawings, which shows the following:

in figure 1. The scheme is known from the prior art, where:

1 - band-pass filter (PF);

2 - matched filter (SF);

3 - balanced modulator (BM);

4 - demodulator (DM);

5, 11, respectively, the first and second block decoders (DC);

6 - recipient of information (PI);

7 - chopper receiving signal block (PPBS);

8 - calculator stray signal bias (IPN);

9 - digital signal offset compensation device (CCU);

10 - decisive block character (RBS);

12 - memory block (PAM) of the samples of the recipient signal;

figure 2. Signal and signal fading;

figure 3. Distortions of the meander;

figure 4. Carrier frequency reception

figure 5. The signal of the component vectors;

in Fig.6. The phase shift of the components;

in Fig.7. Signal modulation meander;

on Fig. Square wave distortion from phase shift of oscillations φ _r ;

Fig.9. Scheme of the claimed device for receiving high-speed information of a space radio link, where:

1 - band-pass filter (PF);

2 - matched filter (SF);

3 - balanced modulator (BM);

4, - demodulator (DM);

5, 11 - the first and second block decoder (DC);

6 - recipient of information (PI);

7 - chopper receiving signal block (PPBS);

8 - calculator stray signal bias (IPN);

9 - digital signal offset compensation device (CCU);

10 - decisive block character (RBS);

12 - memory block (PAM) of the samples of the recipient signal;

13, 14 - the first and second converters;

figure 10. The area of erroneous decisions of the decisive character block.

The essence of the claimed utility model is as follows.

Reception of clock signals and digital information by the receiving device. The scheme uses block reception in numerical information. The bit depth of the received number is set a priori. The receiving device synchronizes the reception of the radio signal, synchronizes the clock frequency of the reception of bits, provides frame synchronization. Synchronous detection in the synchronization channel uses phase-locked loop (FAP) [2, p.203-215, 237]. At the time of entering into communication, numerical information is not accepted.

The following notation is used in the description:

ICH - “initial number”, which is to be transmitted over the radio line and the number obtained as a result of decoding, transmitted to the recipient;

HRE - operator for converting the number of a number system 256 into a number of a binary number system

The transmitting side performs the conversion: - encoding the block of transmitted information - receiving binary characters (IF), which is to be transmitted in the radio lines - converting the IC into the number system 256 (for transmission over the radio line).

Band-pass filter (PF) 1, matched filter (SF) 2, balanced modulator (BM) 3, demodulator (DM) 4, first converter 13, first block decoder (DC) 5, information receiver (PI) 6 connected in series respectively receive and I process information in real time. A radio signal is received at the input of a band-pass filter (PF) 1, which limits the reception bands at the radio frequency, filter the radio signal with the search function, capture and monitor the signal spectrum with a matched filter (SF) 2, transfer the signal to the intermediate radio frequency, compensate for the Doppler shift and delay by a balanced modulator (BM) 3, convert the radio signal into a video signal, analog-to-digital conversion of the phase signal into a sequence of digital reports "0" and "1" by the first demodulator (DM) 4, conversion of the form of numbers and the information unit of the numeral 256 in binary notation system of the first converter 13, error control decoding is performed and correct a limited number of errors in the information bits of the first frame of a block decoder (DC) 5 is transmitted to the recipient information (PI) 6.

The numbers of the number system 256 are transmitted to the radio lines. Each digit of the number contains one of two hundred and fifty-six characters: “0”, “1”, “2” ... “255”. In the designation of characters used binary number system. Symbols are written down and transmitted in higher digits forward. Each character is placed in an octet (eight digits). The symbol "255" occupies the entire octet. The remaining characters occupy the right side of the octet, the left side is filled with "0". To separate the digits during transmission over the radio link, the digits of the number are separated by octets of zeros.

Example 1. The number 324294967296 = 2 ³² -1 in the number system 256 with the number of digits 5, contains the digits 01001011, 10000001, 01111100, 10000000, 00000000, placed in ten octets:

The previous three lines will contain the data: the digit number number - the first line; the content of bits and separators - the second line; the contents of the digits giving the sum 324294967296 in the decimal number system is the third line.

A number from 324294967296 = 2 ³² -1 in the binary number system contains the series 111111111111111111111111111111111111. Numbers from 1 to 324294967296 = 2 ³² -1 in the binary number system contain longer series compared to the number system 256. When modulating KIM-FM with binary system numbers numbering (in the prototype) for each category containing "0" corresponds to 0 deg., "1" corresponds to 180 deg. Then for numbers:

the shortest character contains a beat. A 32-bit series may appear in an information block. The binary number system uses two characters “0” or “1” in a digit.

The maximum series length of one octet of the number system 256 makes the spectrum further away from the carrier frequency than in the binary number system. The noise band of the matched reception is narrowed, the interference of the synchronization channel bandwidth is reduced. When analyzing the KIM-FM signals [2, Fig.5.3.2], it was shown that the noise component leads to an error of the decision block of the symbol

According to the status information of the decoder (DC) 5, the phase signal from the second output of the demodulator is entered into the memory block (PAM) of the samples of the recipient signal 12, and the IPU 8 and the CCU 9 are turned on by the “On” command of the ACS 7. The IPC 8 and CCU 9 units determine and compensate for stray phase signal displacement, RBS 10 - restores the symbols “0”, “1” from the phase signal, the second converter 14 converts the number of the number system 256 into the number of the binary number system, the second block decoder (DC) 11 decodes the transmitted number, the original number is received P receiver (PI) 6.

According to the first option, the first 13 and second converters 14 contain the number conversion operators (HRE), the number of the number system 256 is converted to the number of the binary number system by removing the separator bits and recounting the contents of the bits. Shown as an example 1.

According to the second option, the first 13 and second converter 14 contain the received number conversion operator (HRE), the number of the number system 256 translates into the number of the binary number system by removing the separators of the digits. For this case, a different number system 256 is formed on the transmitting side by simply transferring the contents of the octets of the IC to its bits, with the installation of the separators of the bits one octet in length. HRE forms an IF by removing octets separating the digits of the number of the number system 256. It is shown in Example 2.

Example 2. In this case, the transmitted number IF = 324294967296 = 2 ³² -1, containing the series 1111111111111111111111111111111111, on the transmitting side will be reduced to

00000000 11111111 00000000 11111111 00000000 11111111 00000000 11111111. In the receiving device, in the first 13 and in the second converters 14, the HRE operator converts the code

00000000 11111111 00000000 11111111 00000000 11111111 00000000 11111111 to the IC code 1111111111111111111111111111111111 of the binary number.

The occurrence of information loss from the Doppler effect is affected by the frequency discrepancy. The frequency difference also arises from the Doppler effect. The difference frequencies Δf and Δf _d , where the difference Δf = f ₂ -f ₁ when there is no Doppler effect; Δf _d , there was a Doppler effect, form a discrepancy ƒ _r = Δf _d -Δf. The discrepancy ƒ _r forms a phase shift of the oscillations φ _r , during the time t of the signal propagation before reception, φ _r = mod _2π 2π · ƒ _r · t . The values of φ _r can be different, including zero and π, with a period of circular discrepancy frequency Ω _D = 2π · ƒ _r .

It is known to use the discrepancy (two-frequency phase determination) to determine the electron density of the ionosphere. Take harmonic oscillations with the frequency ratio f ₂ = kf ₁ [5, p. 185], the difference frequencies Δf and Δf _and , where Δf = f ₂ -f ₁ is the difference frequency in free space before the ionosphere, Δf _and is the difference frequency the passage of the ionosphere at k = 3, determine the discrepancy ƒ _r = Δf _and -Δf, which determine the phase shift and the electron density.

EXAMPLE frequency differences and changes in the waveform can be seen at a modulation carrier frequency meander case of oscillations of radiation in one sideband, distortion 8, ω ₀ + Ω = 2π · ƒ _H, ω _{0 + kΩ = 2π · ƒ B,} k = 3. When receiving a signal in the absence of Doppler offsets, the shape of the received signal is shown in figure 3 "a". Dimension of frequency values Hz. Carrier frequency ƒ ₀ = 11000 × 10 ⁶ , components ƒ _H = 11000 × 10 ⁶ + 5 × 10 ⁶ , ƒ _B = 11000 × 10 ⁶ + 15 × 10 ⁶ difference frequency Δf = ƒ _B -ƒ _H = 10 * 10 ⁶ . Doppler carrier frequency offset

50 × 10 ³ , ƒ _0Д = 11000 × 10 ⁶ + 50 × 10 ³

ƒ _ND = 11000 × 10 ⁶ + 50 × 10 ³ + 5 × 10 ⁶ +22.72

ƒ _VD = 11000 × 10 ⁶ + 50 × 10 ³ + 15 × 10 ⁶ +68.18

Difference frequency Δf _d = ƒ _VD -ƒ _ND = 10 × 10 ⁶ +45.46

The discrepancy ƒ _r = Δf _d -Δf = 45.46.

The discrepancy in the coherently radiated frequencies leads to the formation of a phase shift φ _r = π, we obtain t _S = 11 ms. For 11 ms, the wave travels 3.3 thousand km. The oscillation phase of figure "b" of Fig. 8 has changed relative to "b" of Fig. 7. The divergence of the component frequencies of the meander at a receiving range of 3.3 thousand km is illustrated in Fig.8 "b", the distortion in Fig.8 "c", Fig.4 "Guards".

When receiving, the following is performed: PLL synchronization of a signal at a frequency of ƒ ₀ d, PLL synchronization of receiving a meander bit of a frequency of 5 × 10 ⁶ +22.72, synchronization of reception of a block of numbers. The reception of numerical information is bitwise. From distortion of the phase signal of the block of numbers, areas of erroneous decisions arise, which is illustrated in Fig. 10. The decisive device (RBS) uses the samples of the phase signal of the next bit to restore it. Depending on the location of the area of erroneous decisions and how many samples determine the bit, the EinSS may give an error in determining the bit “1” or its absence “0”. Signal loss (loss of synchronization) can arise from the fading of the signal or its component frequencies, which can occur when the frequencies of the left and right spectral components diverge from the Doppler effect.

Implementation of the claimed technical solution allows to reduce the possibility of distortion and signal loss from the Doppler effect depending on the reception range, with bitwise transmission of numerical information. This effect of the circuit is obtained from the introduction of the number system 256 in the method of generating bits of the transmitted number.

Bibliography.

1. Patent for invention No. 2371845. Digital Information Radio 2009

2. Berezin L.V. and Weitzel V.A. Theory and design of radio systems, M., "Soviet Radio", 1977

3. I. M. Teplyakov and others. Radio transmission systems, M., "Radio and communications", 1982

4. Trakhtman A.M. Introduction to the generalized spectral theory of signals. M. "Soviet Radio", 1972

5. Grudinskaya G.P. Propagation of radio waves. Moscow Higher School, 1975

Claims (3)

1. A radio reception device for high-speed information of a space radio line containing a bandpass filter (PF), a matched filter (SF), a balanced modulator (BM), a demodulator (DM), the first and second block decoders (DK), the receiver of information (PI), the receiving chopper a signal block (BSS), a signal stray signal calculator (SPS), a digital signal bias compensation device (CCU), a symbol solving block (RBS), a memory block (PAM) of the receiver signal samples, the first and second converter, while the input of the bandpass filter ( PF) is with the input of the device, a band-pass filter (PF), a matched filter (SF), a balanced modulator (BM), a demodulator (DM), a first converter, a first block decoder (DC), an information receiver (PI) are connected in series, respectively, the second output of the demodulator ( DM) is connected to the input of the block of memory (PAM) of the samples of the recipient signal, the second output of the first block decoder (DC) is connected to the input of the chopper of the reception of the block of signals (BPS), the output of which is connected to the first inputs of the stray signal bias calculator (VPS) and digital devices signal offset compensation (CCU), the IPN output is connected to the second input of the AMC, the SAM output of the receiver signal is connected to the second input of the IPM and to the signal third input of the AMC, the output of the AMC is connected to the input of the symbol decider (RBS), the output of which is connected to the input of the second chopper, the output of the second chopper is connected to the input of the second block decoder (DC), the signal output of which is connected to the second input of the recipient of information (PI). 2. The device according to claim 1, in which the first and second converters contain a number conversion operator (HRE), which translates the number of the number system 256 into the number of the binary number system. 3. The device according to claim 1, in which the first and second converters contain a number conversion operator (HRE) of the number system 256, which translates the number of the number system 256 into a binary number system by removing octets that separate the digits of the number of the number system 256.