SU809645A2 - Phase-manipulated pseudorandom signal receiving device - Google Patents

Description

The invention relates to radio communications and can be used to process phase-shifted signals in discrete information transmission systems, radar systems, and in combined communication systems.

By main auto 555556 out of. A device is known for receiving phase-manipulated pseudo-random signals, comprising a first multiplier, a phase locked loop, a synchronous detector, a delay tracking unit, an information isolation channel and a control unit, to the second input of which 15 is connected an output of a pulse shaper, a delay element whose output is connected with the input of the second multiplier, the second input of which is connected to the input of the delay element, and series-connected phase detector, low-pass filter and a clock generator, the output of which is connected to the first input of the phase detector, while the input of the first alternator is connected to the second input of the synchronous detector, the output of which is connected to the second input of the information extraction channel, and the output of the control unit is connected to the second input of the tracking unit behind the delay, also containing in series connected, a differentiating unit and a comparator, the output of which is connected to the input of the pulse shaper, and the input of the delay element is connected to the input of the first gear multiplier, the second input of which the output of the delay tracking unit is connected, and the low-pass filter output is connected to the input of the differentiating unit, while the output of the second multiplier is connected to the second input of the phase detector [1]. However, the known device has a significant dispersion of determining the start time of a pseudo-random signal, i.e. the root-mean-square deviation of the target designation pulse taken from the pulse shaper is large (it can reach, for example, 0.1 of the period of the pseudorandom sequence (PSP) ·, which can amount to thousands or more elementary samples of the PSP), and therefore the time of entering the synchronous mode is relatively large .

The purpose of the invention is to reduce the time of entry into synchronous mode.

This goal is achieved by the fact that in the device for receiving faeomani3 pulsed pseudo-random signals containing a series-connected first multiplier, a phase-locked loop, a synchronous detector, a delay tracking unit, an information extraction channel and a control unit ', to the second input of which a pulse former is connected, a delay element, the output of which is connected to the input of the second multiplier, the second input of which is connected to the input of the delay element, and phase-connected in series a detector, a low-pass filter and a clock, the output of which is connected to the first input of the phase detector, while the input of the first multiplier is connected <to the second input of the synchronous detector, the output of which is connected to the second input of the information extraction channel, and the output of the control unit is connected to the 20 second input a delay tracking unit, which also contains a differentiating unit and a comparator in series, the output of which is connected to the input of the pulse shaper, 'the input of the delay element being connected to move the first multiplier, to the second input of which is connected to the output of delay tracking unit, and the output of the lowpass filter is connected. with the input of the differentiating unit, while the output of the second multiplier is connected to the second input of the phase detector, a time interval meter, a clock phase detection unit, and a code-interval converter, the second input of which is connected to the output of the clock generator and the first input of the time meter, are additionally introduced interval, the second input of which is connected to the output of the pulse shaper, the second input of the phase detection unit of the clock pulse and the third input of the converter code -interval, the fourth input of which is connected to the third input of the phase determination unit of the clock pulse and the output of the channel for selecting information, and the output of the code-interval converter is connected to the second input of the control unit. jq

On the fourth shows a structural electrical diagram of a device for receiving phase-manipulated pseudo-random signals. __

The device comprises a first resident ³³ resident 1, a phase adjustment block 2, a synchronous detector 3, a delay tracking unit 4, an information allocation channel 5, a control unit 6, and a synchronization channel 7, which contains a delay element 8, the second a multiplier 9, a phase detector 10, a low-pass filter 11, a differentiator block 12, a comparator 13, a pulse shaper 14, a clock generator 65, a time interval meter 16, a clock phase determination unit 17, and a code-time converter 18.

The proposed device operates as follows.

In the synchronization mode, the input phaeomanipulated signal according to the law of binary SRP is fed to the input of the device and in the first multiplier 1 is converted to a harmonic signal as a result of multiplication with a reference binary signal coming from the output of the delay tracking unit 4 and filtered by the phase-locked loop 2. The same input signal in the synchronous detector 3 is converted into a binary sequence, since the second input receives a harmonic signal from the output of phase-locked loop 2. The selected binary signal enters the delay tracking unit 4 and the information extraction channel 5. The delay tracking unit 4 monitors the temporal position of the demodulated signal by correlating the temporal position of the reference pseudo-random signal. Channel 5 allocation of information by comparing the reference sequence with the received carries out the selection of information pulses that are received at its first input and signal the presence of synchronization. The signal about the presence or absence of synchronization from the output of the channel 5 information allocation is supplied to the control unit 6. In the absence of synchronization, the control unit 6 connects the output of the synchronization channel 7 to the installation input of the delay tracking unit 4. In this case, the pulses of the synchronization channel 7, carrying information about the temporary position of the received signal, return the receiver to the synchronism position.

The operation of channel 7 synchronization is as follows.

The signal from the input of the receiving device enters the clock frequency separation circuit formed by the delay element 8 and the second multiplier 9. In this case, the reproduction spectrum of the phase-manipulated pseudo-random signal and the same signal, shifted in time by half the clock frequency period, contains the clock component of the pseudo-random signal. The signal from the output of the clock frequency isolation circuit enters the phase-locked loop formed by the series connection of the phase detector 10, the low-pass filter 11, the clock generator 15, covered by feedback, and filtered by it. Due to the fact that the manipulation of the pseudo-random signal by the delay results in the manipulation of the clock phase by 180 °, the phase of the allocated oscillation of the clock frequency changes in accordance with binary information messages that are linked in time position to the beginning of the pseudorandom signal sequence. Moreover, the moments of phase manipulation of the oscillations of the clock frequency cause a characteristic transition process in the phase-locked loop. By the maximum of this transient process, the moment of phase and phase manipulation and the temporary position of the beginning of the pseudo-random signal are determined. For this purpose, the differentiating unit 12, the comparator 13 and the imager 14 are serially connected. pulses. Determination of the temporal start of the pseudo-random signal allows the receiver to enter the synchronization mode, however, based on the analysis of the device, we can assume that the deviation of the temporal position of the clock from the true temporal position of the beginning of the SRP is random and has a normal distribution law with zero mean and dispersion Thus, the synchronization mode is achieved if the sync pulse sets the reference SRP in the block capture zone. 4 delay tracking. This zone is, as a rule, two elementary ed discrete PSP 2T.

The clock pulses from the output of the shaper 14 pulses are fed to the inputs of the block 17 determine the phase of the clock pulse, the meter 16 time interval and the converter 18 code interval. As a result of the operation of the time interval meter 16, its output contains a number in a binary multi-bit code corresponding to the measured time interval 40 between adjacent clock pulses in the time interval of the clock frequency pulses, which are supplied to the second input of the time meter 16 of the time interval from the output of the clock generator 15. V block 17 determining the phase of the clock determines the number of the clock received at the input, and depending on this number and the size of the time interval, m Between clock pulses, the estimate of which is supplied to the second input of block 17 from the output of meter 16, an estimate of the phase of the clock pulse is calculated taking into account the accumulated information about previous pulses. The third input of block 17, connected to the output of the information extraction channel 5, serves to reset the existing counters to the initial state when synchronism is achieved and thereby prepares the device for further operation in the event of failure in the tracking unit 4 for tracking the delay. An estimate of the phase of the clock pulse from block 17 is fed to the input of the converter 18 in a code-interval, at the output of which a clock pulse is generated with a phase f depending on the corresponding estimate generated in block 17. The second input of the converter 18 is connected to the output of the clock generator 15, since it requires a clock frequency . The first clock from the output of the driver 14 passes directly to the output of the converter 18, because at the first moment there is no additional information for its displacement.

The fourth input of the transducer 18 is connected to the output of the information extraction channel 5 and serves to set the initial state of the transducer 18 of the code interval when synchronism is achieved.

Thus, the introduction of a time interval into the measuring device, a sync pulse phase determination unit, and a code-interval converter reduces the time it takes for the device to enter synchronism.

Claims (1)

The invention relates to radio communications and can be used for processing phase-shift keyed signals in discrete information transmission systems, radar systems, and in combined communication systems. According to the main auth. 555556, a device for receiving phaeomanipulated pseudo-random signals is known, comprising a first multiplier connected in series, a phase locked loop, a synchronous detector, a delay tracking unit, an information extraction channel and a control unit, to the second input of which the pulse shaper output is connected, the delay element whose output connected to the input of the second multiplier, the second input of which is connected to the input of the delay element ,, and the phase detector connected in series, the lower filter frequency and clock generator, the output of which is connected to the first input of the phase detector, the input of the first multiplier is connected to the second input of the synchronous detector, the output of which is connected to the second input of the selection channel, and the output of the control unit behind the delay, also containing series-connected, differentiating unit and -comparator, the output of which is connected to the input of the pulse former, and the input of the delay element is connected to the input of the first peremimo It has an output of a delay tracking unit, and a lowpass filter output is connected to the input of a differentiating unit, while the output of the second multiplier is connected to the second input of phase detector 1. However, the known device has a significant variance for determining the pseudo-random signal start time, t . the mean square deviation of the target indication pulse taken from the pulse former is large (it can reach, for example, 0.1 of the pseudo-random sequence period (PSP) which can amount to thousands and more elementary PSP samples) and therefore the time of entering the synchronous mode relative to the scope of the invention is The abolition of the time of entry into the synchronous mode. The goal is achieved by the fact that a device for receiving phase-shifting pseudo-random signals comprising a first multiplier connected in series, a phase locked loop, a synchronous detector, a delay tracking unit, an information extraction channel and a control unit, the second input of which is connected to a pulse driver, a delay element , the output of which is connected by the second multiplier input, the second input of which is connected to the input of the delay element, and the series-connected phases detector, low pass filter and clock generator, the output of which is connected to the first input of the phase detector, the input of the first multiplier is connected to the second input of the synchronous detector, the output of which is connected to the second input of the information channel, and the output of the control unit is connected to the BTOpfcDvi input the delay tracking unit, which also contains a successively connected differentiating unit and a comparator, the output of which is connected to the input of the pulse former, and the input of the delay element is connected to Odom first multiplier, to the second input of which is connected tracking block output d of delay, and the output of the lowpass filter is connected to the input of the differentiating block, the output of the second multiplier under. CLUSED to the second input of the phase tuner, the time interval meter connected in series, the sync pulse phase detection unit and the code-InterN converter, the second input of which is connected to the output of the clock generator and the first input of the time interval meter, the second input of which is connected to the output of the pulse generator, are additionally introduced. the second input of the clock phase determining unit and the third input of the code-interval converter, the fourth input of which is connected to the third input of the unit laziness f PS clock and output channel you dividing information, and an output transducer code-interval in rum is coupled to the input of the control unit. On the even side, a structural electrical circuit of the device is shown for receiving phase-manipulated pseudo-signal signals. The device contains a first alternator 1 ,. block 2 phase. auto-tuning, synchronous detector 3, delay tracking unit 4, information extraction channel B, control unit 6 and synchronization channel 7, which contains delay element 8, second alternator 9, phase detector 10, low-pass filter 11, differentiating unit 12, a comparator 13, a pulse shaper 14, a clock oscillator op 15, a time integral meter 16, a sync pulse pulse detection unit 17, and a code-interval converter 18. The proposed device works as follows. In the synchronization mode, the input phased signal according to the law of the inverse memory bandwidth arrives at the input of the device and in the first multiplier 1 is converted into a harmonic signal as a result of multiplication with the reference signal received from the output of the delay tracking unit 4, and it is not phase auto-tuned. The same input signal in the synchronous detector 3 is converted into a binary sequence, since its second input receives a harmonic signal from the output of the phase locked loop 2 unit. The selected binary signal enters the delay tracking unit 4 and the information extraction channel 5. The delay tracking unit 4 monitors the temporal position of the demodulated signal by correlating the temporal position of the reference pseudo-random signal. The channel 5 for extracting information, by comparing the reference sequence with the received one, carries out the selection of information pulses, which arrive at its first input and signal the presence of synchronization. The signal about the presence or absence of synchronization from the output of the information extraction channel 5 goes to the control unit 6. In case of no synchronization, the control unit b connects the output of the synchronization channel 7 to the setup input of the delay tracking unit 4. In this case, the pulses of the synchronization channel 7, carrying information about the temporary position of the received signal, return the receiving device to the synchronism position. The operation of the synchronization channel 7 is as follows. The signal from the receiver input enters the clock selection circuit formed by the delay element 8 and the second multiplier 9. At the same time, in the reproduction spectrum of the phase-shifting pseudo-random signal and the same signal, shifted in time by half the period of the clock frequency, there is a component of the pseudo-random frequency signal. The signal from the output of the clock selection circuit enters the phase-locked loop, which is formed by sequentially turning on the phase detector 10, the low-pass filter 11, the clock generator 15, covered by feedback, and filtered by it. Because the delayed pseudo-random signal manipulation causes the clock frequency to be manipulated by 180, the phase of the extracted clock frequency fluctuates in accordance with the binary information signals, which are linked in their temporal position to the beginning of the pseudo-random signal sequence. At the same time, the moments of phase manipulation of oscillations of the clock frequency cause a characteristic transition process in the phase-locked loop. From the maximum of this transient process, the moment of phase manipulation and the temporal position of the beginning of the pseudo-random signal are determined. For this purpose, serve in series the differentiating unit 12, the comparator 13 and the driver 14 pulses. Determining the time base of a pseudo-random signal allows the receiver to be inserted into synchronization modes, however, from the. analysis of the device, it can be assumed that the deviation of the temporal position of the sync pulse from the true temporal position of the beginning of the bandwidth is random and has a normal distribution law with zero mean and variance 6- Thus, the synchronization mode is achieved if the sync pulse sets the base bandwidth to the zone capture block. 4 delay tracking. This zone, as a rule, constitutes two elementary PTS 2T sampling. The sync pulses from the output of the pulse generator 14 are fed to the inputs of the sync pulse phase detection unit 17, the time interval meter 16 and the code interval converter 18. As a result of the operation of the time interval meter 16, its output contains a binary multi-digit code corresponding to the measured time interval between adjacent clock pulses on a scale of the clock pulse frequency interval, which is fed to the second input of the time meter 16 from the clock generator 15 output. In block 17 for determining the phase of the sync pulse, the number of the sync pulse received at the input is determined, and depending on this number and the value of the time interval, between the sync pulses, the evaluation of which arrives at: the second input of block 17 from the output of the meter 16, calculates the sync pulse phase estimate taking into account the accumulated information on previous pulses. The third input of the unit 17, connected to the output of the information extraction channel 5, serves to reset the available counters to the initial state when synchronization is achieved, and thus prepares the device for further work in case of a failure in the delay tracking unit 4. The evaluation of the phase of the sync pulse from block 17 is fed to the input of the code interval converter 18, the output of which is formed with a phase pulse depending on the corresponding estimate formed in block 17. The second input of the converter 18 is connected to the output of the clock generator 15, since its operation requires clock frequency. The first sync pulse from the output of the imaging unit 14 passes directly to the output of the converter 18, since at the first moment there is no additional information to displace it. The fourth input of the converter 18 is connected to the output of the information extraction channel 5 and serves to reset the code interval converter 18 upon reaching the synism. Thus, the introduction of a time interval into the device, a sync pulse phase detection unit and a code-interval converter, leads to a decrease in the device's time for synchronization. Apparatus of the Invention A device for receiving phase-shift keyed pseudo-random signals according to the main auth. 555556, that is, in order to reduce the time of entry into the synchronous mode, a time interval meter, a sync pulse phase detection and conversion unit are entered into it. Code-interval detector, the second input of which is connected to the output of the clock generator and the first input of the time interval meter; determining the phase of the pulse and the output of the information clearing; and the code-interval converter output is connected to the second input of the control unit. Sources of information, rintye taken into account during the examination 1. USSR author's certificate 555556, cl. H 04 L 27/22, 1975.