Method for harmonic geometrical signal modulation

FIELD: automatic data acquisition systems.

SUBSTANCE: proposed method designed for data acquisition from burglar and fire alarm sensors, electricity, heat, and gas meters, and from fiscal memory of cash registers involves use of unique random or pseudorandom plurality of differences in initial phases of closest harmonic pairs, mentioned plurality being chosen so as to minimize peak factor of total signal. In case of operation of fire alarm sensor it is sufficient to transfer only one character to alarm control console unambiguously identifying location of operating sensor; as a rule, such character is conditional number or address pre-assigned to sensor.

EFFECT: reduced power requirement of subordinate system units and/or enhanced range of their operation.

1 cl, 2 dwg

 

The invention relates to techniques for data collection and alarm systems for distribution networks, AC and can be used for low-speed data acquisition from remote sensors, security and fire alarm systems, energy meters, flow of heat, water, gas, etc.

Known communication system for distribution of AC (U.S. patent No. 5844949, CL N 04 001/10; H 04 L 025/08; H 03 D 001/04, from 01.12.1998 G.), consisting of a transmitter emitting a signal with geometric harmonic modulation, and receiver for receiving and decoding. The main disadvantage of this communication system is that to encode the transmitted signal uses relative phase modulation (there) on each of the emitted harmonics. This circumstance does not allow energy to effectively communicate information in small portions, such as one bit or one character at a time, since there for transfer of one bit or symbol you want to radiate at least two signals, and reference information.

Also known communication system on AC power (U.S. patent No. 6329905, CL H 04 M 011/04, from 23.03.2000,) transmitter which emits a signal consisting of two harmonics with relative phase modulation between them, and the frequency of these harmonics multiple of p is half the fundamental frequency of the mains voltage. The main disadvantage of this system is its deliberately low immunity related to the fact that the data it uses a signal whose energy is concentrated only in two narrow areas, so that the presence of periodic noise, the frequency of which happened to coincide with one of the transmit frequencies, will make such a communication system is completely down. In addition, since the frequencies of these harmonics are quite different from each other (at times), and their relative phase at the point of reception will be strong and randomly fluctuate relative to each other simultaneously with the fluctuations of the frequency-phase characteristics of the signal distribution environment that will make it impossible to decode the signal at the receiving end.

The objective of the invention is to create a modulation signal based on transmission data in small chunks (e.g., one bit) over large intervals of time, more energy efficient than currently known, which would in the most adverse noise conditions and in the presence of a strong attenuation of the signals to collect data from a large number connected to AC power low-speed sensors, such as, for example, sensors, security and fire alarm systems.

The technical result - the reduction of e is ergometrine transmitters subordinate nodes of the system and increase the range of its validity. This technical result in the implementation of the present invention is achieved by the fact that in contrast to known methods, as the object of modulation used, the phase difference of adjacent harmonic components of the signal, compared to traditional there allows you to halve the duration of the information signal while preserving the characteristics of its noise immunity. Note that this prize will take place only when transferring small amounts of data, such as one bit, or in a broader interpretation - one character. In many practical cases this is enough, for example in the case of actuation of the fire alarm sensor enough to send remote alerts only one symbol that uniquely identifies the location of the triggered sensor (typically, this symbol is the conditional number or address pre-assigned to the sensor).

Conducted by the applicant's analysis of the prior art, including searching by the patent and scientific and technical information sources to identify sources that contain information about the equivalents of the claimed invention, allows to establish that the applicant is not detected similar, characterized by symptoms that are identical to the characteristics of the claimed invention, and the definition of PE is ecna identified unique prototype as the most similar set of features analogue, helped to identify a set of essential towards perceived by the applicant to the technical result of the distinctive features in the claimed object set forth in the claims. To verify compliance of the claimed invention to the requirement of inventive step was conducted an additional search of features that match the distinctive features of the prototype of the claimed invention, the results of which show that the claimed invention is not necessary for the expert in the obvious way from the prior art, since no known technical solution, in which modulation signals are phase difference of a large number of neighboring harmonic signal components.

The inventive method geometric harmonic modulation signal, the modulation signal is illustrated by drawings.

1 shows a block diagram of a data collection system AC power from a large number of fire alarm sensors, which uses the proposed modulation method.

Figure 2 shows a diagram illustrating a principle of forming timestamp primary (bit) synchronization.

The implementation of the invention will be demonstrated on the example data collection system from the fire alarm sensors (figure 1), which consists of one main is on node 1 and several slave nodes 2. All nodes of the system are connected electrically to the same segment of the power line 3. Internal structure of the master and slave nodes is very similar and includes the following elements: block, protect, and pairing signals 4, the band-pass filters 5 and 6, an analog-to-digital Converter 7, a d / a Converter 8, a comparator with hysteresis 9, the interrupt input 10. The difference lies in the fact that the main host system is executed on the basis of a powerful processor, digital signal processing 11 and phase tables 12, and a processor for digital signal processing has a channel of communication with the outside world 13, and a simpler and cheaper subnode entirely performed on the universal microcontroller 14 and the signal table 15, and to the microcontroller 14 via the communication line 16 is connected the primary fire alarm sensor 17, such as a smoke detector. Operating frequency range of the system 20... 95 kHz. The signal from the slave node is transmitted in the range of 96 harmonics, separated from each other by exactly 781,25 Hz.

The data collection system operates as follows (Fig 1, 2). The Comparators 9 highlight the moments when mains voltage 18 becomes zero 19, forming, thus, almost simultaneous to the whole system a sequence of time stamps 20, which serves for primary (character) synchronization Ave is in the process of data transfer from the slave nodes to the master.

When triggered, the primary sensor 17, the microcontroller 14 starts periodically play through the DAC 8 its stored in permanent memory and is unique for each slave node 2, the signal table. The duration of the "play" signal tables exactly equal to one half period of the mains voltage and the beginning of "play" is determined by the triggering of the comparator 9, which occurs at the moment of equality to zero voltage on the line 3. The output signal from the DAC 8 is then bandpass filtered by filter 6 to remove from his out-of-band components and through the protection unit and the coupling 4 is fed to a network line 3. Signal table 15 is unique to each of the slave nodes 2. Many signal tables is synthesized prior to the deployment of network data collection using the following method. Using random or pseudo-random numbers generated by a multiple-candidate of 96 numbers ϕ belonging to the interval [0... 2π [. Next, this set is used for the synthesis signal of the form

where m=0... 95, a fm- 96 equally spaced from each other harmonics located increments 781,25 Hz in the frequency of the system (20... 95 kHz). The signals s(t) with good value, peak factor and sets the phase for them are stored in the form of a t the blitz for future use. As practice shows, the probability that this random set of 96) difference of the phases will be synthesized signal with crest factor, which will play peak-factor pure sine only 4 dB, is quite high. When deploying the system selected in the above way different signaling table is recorded in each of the slave nodes 2. The signal transmitter of the slave node passes through the segment of the power line 3, which is folded noise is attenuated, is exposed to various types of linear and nonlinear distortions and enters the main network node 1, where it passes through the interface unit 4, the bandpass filter 5 and is digitized in the ADC 6. The digital signal processor 13 stores all sampling ADC, owned by a given bit interval, and produces them over the operation of the fast Fourier transform (FFT). The result of this operation is the set of complex Fourier coefficients from which to implement further actions are only 96 coefficients, the frequency of which coincides with the frequency at which the slave node transmits its data will be denoted further as Cmwhere m=0... 95. At the next stage are calculated works

where Δ ϕkkk-1that ϕmthe corresponding set f is, taken from the phase table 12, which was used to generate a signal tables this subordinate node, k=1... 95, m=0... 95, and the asterisk means complex conjugation. Next, for each slave node calculates the score as the sum of

S=∑ sign{Re(Dk)}.

The meaning of these actions is that works Withk·(Ck-1)*are complex vectors, the angles of rotation which is equal to the difference of the phases of neighboring harmonics in a received signal, and a value of Dkthe same vectors, only "Governate" towards the real axis by an angle exactly opposite to that which was used to modulate these harmonics in the transmitter of the slave node. Thus, if a given bit interval "correct" signal from the slave node corresponding to the group of complex numbers Dkbegin to concentrate along the direction of the real axis, and the sum S will show a large positive deviation. If this bit interval of the useful signal from the slave node is not that it is easy to see the value of S will be a normally distributed random value with zero mean and standard deviation of about 10 units. The detection signal from the slave node then concludes with a comparison S with some pre-selected sufficiently large threshold.

Compared to known methods of geometric harmonic modulation of the above-described signal is two times less effective duration, which allows in the same time to lower the power consumption of the slave node while maintaining all of the characteristics of the noise immunity of the system.

Thus, the above data confirm that the implementation of the use of the claimed invention the following cumulative conditions:

the tool embodying the claimed invention in its implementation, is intended for use in Powerline communications, namely, data acquisition systems from remote sensors;

for the claimed invention in the form as it is described in the independent claims, confirmed the possibility of its implementation using the above in the application or known before the priority date tools and methods;

the tool embodying the claimed invention in its implementation, is able to achieve perceived by the applicant of the technical result.

The method of geometric harmonic modulation signal consisting of a set of equally spaced from each other in frequency harmonics in the data collection system on AC power, wherein to encode each SIM is Ola transmitted data using a unique random or pseudorandom many differences in the initial phases of the nearest pairs of the above harmonics, these many differences, the initial phase is chosen so as to minimize the crest factor of the total signal.



 

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FIELD: electricity supply power network communication.

SUBSTANCE: moments at which main harmonic of power voltage of supply-line voltage crosses zero level are used as events of symbol synchronization.

EFFECT: simplified design; improved performance in terms of error probability.

5 cl, 3 dwg

FIELD: electricity supply power network communication.

SUBSTANCE: moments at which main harmonic of power voltage of supply-line voltage crosses zero level are used as events of symbol synchronization.

EFFECT: simplified design; improved performance in terms of error probability.

5 cl, 3 dwg

FIELD: automatic data acquisition systems.

SUBSTANCE: proposed method designed for data acquisition from burglar and fire alarm sensors, electricity, heat, and gas meters, and from fiscal memory of cash registers involves use of unique random or pseudorandom plurality of differences in initial phases of closest harmonic pairs, mentioned plurality being chosen so as to minimize peak factor of total signal. In case of operation of fire alarm sensor it is sufficient to transfer only one character to alarm control console unambiguously identifying location of operating sensor; as a rule, such character is conditional number or address pre-assigned to sensor.

EFFECT: reduced power requirement of subordinate system units and/or enhanced range of their operation.

1 cl, 2 dwg

FIELD: engineering of systems and methods for transferring information via electric supply lines, possible use in alarm systems or systems for automatic collection of data from remote sensors.

SUBSTANCE: during transfer of information along three-phased alternating-current electric network in selected phase of electric network moments of transfer of main harmonic of network voltage over zero with derivative of same sign are determined. Time stamps are made for these moments. Further, exchange of code messages is performed between phases of alternating current electric network. Time span between beginnings of last two generated time stamps is measured. Value of aforementioned time span is recorded. Resulting series of synchronization impulses is produced by generation of three synchronization impulses after expiration of each recorded time span, first impulse starting immediately after expiration of recorded time span, second one - after passage of one third of recorded time span after beginning of first synchronization impulse and third one - after one third of recorded time span after beginning of second synchronization impulse. Exchange of messages between phases of alternating current electric network is realized using transmitting-receiving devices, made with possible receipt and/or transmission of code messages along phases of alternating-current electric network. Also, exchange of code messages between phases of electric alternating-current network is realized using identical reactive connecting devices, connected between phases of alternating-current electric network.

EFFECT: simplified construction and assembly of alarm or data transfer systems for territorially remote objects.

6 cl, 8 dwg

FIELD: technology for transferring information via electric supply lines, possible use in alarm signaling systems.

SUBSTANCE: in phases of alternating-current electric network selected for transferring code messages, moments of transfer of main harmonic of network voltage over zero are determined with derivative of same sign and time stamps are generated in these moments. In moments of beginning of said stamps synchronization impulses are generated. Exchange of symbolic information is realized between phases of electric network selected for transferring code messages. Resulting series of synchronization impulses is received, providing transport function for transferring information in unified communication network. Exchange of symbolic information between phases of electric network is realized with usage of receiving-transmitting device, made with possible receipt and/or transmission of code messages via phases of alternating-current electric network, or using identical reactive connecting devices.

EFFECT: simplified construction and assembly of information transfer systems at territorially distributed objects.

6 cl, 8 dwg

FIELD: automatic data acquisition systems.

SUBSTANCE: proposed method designed for data acquisition from burglar and fire alarm sensors, electricity, heat, and gas meters, and from fiscal memory of cash registers involves use of unique random or pseudorandom plurality of differences in initial phases of closest harmonic pairs, mentioned plurality being chosen so as to minimize peak factor of total signal. In case of operation of fire alarm sensor it is sufficient to transfer only one character to alarm control console unambiguously identifying location of operating sensor; as a rule, such character is conditional number or address pre-assigned to sensor.

EFFECT: reduced power requirement of subordinate system units and/or enhanced range of their operation.

1 cl, 2 dwg

FIELD: radio engineering; portable composite phase-keyed signal receivers.

SUBSTANCE: proposed receiver has multiplier 4, band filter 6, demodulator 8, weighting coefficient unit 5, adding unit 7, analyzing and control unit 10, synchronizing unit 3, n pseudorandom sequence generators 21 through 2n, decoder 1, and switch unit 9. Receiver also has narrow-band noise suppression unit made in the form of transversal filter. Novelty is that this unit is transferred to correlator reference signal channel, reference signal being stationary periodic signal acting in absence of noise and having unmodulated harmonic components that can be rejected by filters of simpler design than those used for rejecting frequency band of input signal and noise mixture. Group of synchronized pseudorandom sequence generators used instead of delay line does not need in-service tuning.

EFFECT: facilitated realization of narrow-band noise suppression unit; simplified design of rejection filters.

1 cl, 8 dwg

FIELD: radio engineering, applicable in antiference radiolinks.

SUBSTANCE: the method is featured by the fact that the pseudorandom sequence with clock pulse fp and for expansion of the spectrum is divided into two orthogonal sequences, one of which contains only even harmonics of the initial pseudorandom sequence, and the other - only the odd ones, then each of the obtained sequence is multiplied with a simple phase-manipulated signal, then the upper side band is separated from the spectrum of one obtained signal, and the lower side band - from the spectrum of the other signal, these unlike side bands are summed up, in each side band two narrow sections of the spectrum symmetrical relative to frequency f0+1/2fp, in the upper side band and relative to frequency f0-1/2fp in the lower side band, one of the separated sections of the spectrum in each side band of the separated spectrum sections is amplified to the known magnitude, and the other, symmetrical to it, is inverted, after which the separated and remained non-separated sections of the spectrum in both side bands are summed up, the separated narrow spectrum sections in each side band are altered according to the pseudorandom law.

EFFECT: enhanced anti-interference of the radiolink is attained due to the fact that in the method of normalization of the composite phase-manipulated signal consists in expansion of the spectrum of the simple phase-manipulated signal obtained by multiplication of the carrying sinusoidal oscillation with frequency f0 and the binary information signal.

6 dwg

FIELD: radio engineering.

SUBSTANCE: device implements algorithms of discontinuous Fourier transformation and fast folding of received and bearing signals, to provide search-less detection of complicated signals with sizeable bases. Digital synchronized filter processes at video-frequency with use of standard digital assemblies and elements. Device has multipliers 3,4,14,15, phase changer 2 for π/2, circuit for delay for length of signal element 1, low frequency filters 5,6, analog-digital converters 7,8,12, microprocessor systems of discontinuous Fourier transformation 9,10, microprocessor systems of reversed discontinuous Fourier transformation 16,17, generator of bearing pseudo-random series 11, microprocessor systems of discontinuous Fourier transformation of bearing pseudo-random series 13, square-ware generators 18,19, adder 20, arithmetic device for taking square root 21, threshold device 22, discontinuous process pulse generator 23, device for splitting frequency in two 24, clock generator 25, interconnected by appropriate functional connections.

EFFECT: broader functional capabilities, higher efficiency.

2 dwg

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