The method of controlling multi-channel sonar reception path
(57) Abstract:Usage: specialized in measurement technology. The inventive method of controlling multi-channel sonar reception path includes a comparison of informative parameters with reference values and decision-making by comparing the results of the technical condition of the receive path. The receive path is placed in the marine environment normal operation, take the acoustic noise of the marine environment, determine the integral value of the absolute values of the output voltages of the channels, which are used as informative parameters, determine the arithmetic average value of informative parameters, which are used as reference values. The reference value is remembered and used in the comparison of informative parameters. 1 C. p. F.-ly, 1 Il. The invention relates to the field of specialized measuring equipment and can be used to control the receive paths and antennas hydroacoustic devices during their operation.The known method based on radiation in the marine environment known reference test signal, measuring output napryajennogo channel, incurred when taking the same test signal 
The disadvantages of this method are the inability to combine the operations of the control circuit and its operation for the full-time appointment, the complexity and high cost of test equipment, the need for radiation known reference test signal, which becomes accessible to an indefinite number of observers.Closest to the invention is a method of diagnostics of electronic components, whereby the input of the control object (the electronic unit, the receive path and other features of the test signal in the selected test points of the test object emit informative parameters and compare them with reference values  By comparing the results to decide on the technical condition of the test object and its parts, the relevant control points.The disadvantage of this method applied to control sonar receive paths is the inability to provide path for the full-time appointment during control test signal. Amid strong test signal (for accurate measurement of informative parameter, as is known, the measured is by the foster tract weak signals of the monitored objects (fish, nodules, etc. become even less visible than the background noise environment.In the proposed method, to ensure the normal operation of a receive path to destination while monitoring the receive path is placed in the marine environment normal operation, take the acoustic noise of the marine environment, determine the integral value of the absolute values of the output voltages of the channels, which are used as informative parameters, determine the average value of informative parameters, which are used as reference values and the reference value is remembered and used in the comparison of informative parameters.The device for implementing the method comprises a multi-element antenna 1, a multi-channel amplifier 2, multi-channel Quad splitter (option uses the multichannel shaper absolute value) 3, multi-channel integrator 4, the switch 5 control unit 6 comparison signals, and flow indicating and control 7.In accordance with the proposed method, the device is placed in the marine environment for operation (ensuring the normal operation of the path signals are removed from the output circuit of the amplifier output 2 using if necessary the is available). Acoustic noise N the surrounding marine environment is taken with the help of antenna elements 1 of the device and increase in the respective channels of the amplifier 2. Additive acoustic noise environment on the antenna elements 1 effect useful for normal operation the signals S of the observed objects (fish or shoals, nodules etc).Thus, for each i-th antenna element 1 affects the signal Xi= Si+Ni.The energy of the Psisignal Sia lot less energy PNiinterference with the normal operation Niunder the terms of the detection signals, i.e., PSi<< PNiand the influence of PSienergy transformations Xi(t) Ni(t) can be neglected.Acoustic noise N of the marine environment in the placement of the antenna 1 in the vast majority of cases the real marine waters can be considered as a Gaussian random process with zero mean and some variance 2(Ocean acoustics. /Ed, Acad. L. M. Brekhovskikh. M. Nauka, 1974, S. 619), i.e., have the probability density
(N) (x) exp-
In sonar receiving paths increase the detection range of the signals using the spatial accumulation of useful signals introduction the cops antenna 1 by a distance sufficient to obtain the statistical independence of acoustic noise on the antenna elements. The increase in the number of channels (antenna size 1) is limited by many circumstances and, in particular, the condition of homogeneity of the acoustic field noise of the marine environment of the installation location of the antenna 1 (heterogeneity can be taken into account by the introduction of weights for the stresses of antenna elements, but it won't work, as it leads to a decrease in the efficiency of normal operation). Increasing the efficiency of staff work contributes to the property of ergodicity, the inherent noise of the marine environment.Thus, the output voltages at the outputs of the amplifier 2 create, affecting acoustic noise with the described properties of the antenna elements 1 with the described properties. Amplified in the amplifier 2, the signals remain in force linear nature of the transformation of a Gaussian random signal source law probability distribution with zero mean (the output voltages of the channels, as a rule, there is no DC component) with an accuracy ratio of the transmission channel can be considered to have equal variance of the input signals Xi, i.e.2. The coefficients of transmission channels operable tra(or their v compensate for the heterogeneity of the acoustic noise of the marine environment of the antenna elements). Without affecting the generality of the analysis, you can take gain a working channel is equal to one.The output voltage of the amplifier 2 serves to corresponding inputs of a Quad 3, and then the signals are passed to the integrator 4. In this form the integral values of the squares of the output voltages of the channels
When Gaussian signals, i.e. as a result of the statistical evaluation of the energy dispersion parameter output voltage of channel path (for a fair evaluation of these considerations about insignificant impact in the energy channels of useful signal).Time T is the time of the control channel and is based on the spectral characteristics of Xi(used for T paths of the order of several seconds).In the variant with the formation of the absolute value get
When Gaussian signals, as is known from theory of linear detector, the value of () is the evaluation , i.e., uniformly and monotonically associated with the evaluation of the energy ratios for useful signals and fair in this case).Consider now that the cause of the randomness of the output voltages of the channels is not only random features is equal to the j-th channel does not pass the signal on the output channel (or has a significantly lower coefficient of transmission). This channel can be regarded as random Gaussian output voltage with zero mean and zero (or substantially small) dispersion Xj(t) N(O, O) and for him
Thus, the selected parameters and do contain information about the state of serviceability or malfunction of the channel.In the adder 8 form the reference value y (for comparison with informative parameter channel) by forming the arithmetic mean of informative parameters of channels or .For example, the number of channels n=10,
1b21b, tohdou (101) 1b2or Y X (101) 1b
In case of failure of one channel (j-th)
Y + (91+10) 0,9 b2< / BR>or
Y + (91+10) 0,9 b2< / BR>i.e., a failure of one of the channels (the failure rate of the sonar channels of receive paths is a single, failed channels immediately restore) very little effect on the reference value when the selected operation of its formation (the selected operation has a "memory" on the informative value of the parameter channel with the described properties that existed prior to the incident channel), while informative parameter channel when you switch to another technical condition is especiay the solution of the technical problem of control channels tract.Note that the formation of the reference value using the specified operation removes the impact of uncertainty (volatility) of the noise level of the marine environment on the correct assessment of the technical condition of the tract. Reducing acoustic noise of the marine environment in comparison with the previous period of operation or by the previous cycle control channel cannot be taken for failure (reduction gear ratio of the channel), so as informative parameter, and the reference value for this reason, change in the same way.In a variant of the method (it is applicable if the amplifier path has a fairly effective AGC or experience of the preceding operation known small variability of the level of acoustic noise environment in this area the water this time of year) the formation of the reference value is performed in the beginning of the operation period and remember it for subsequent cycles of the control. 1. The method of controlling multi-channel sonar receive path, including comparison of informative parameters with the reference value and the decision on the results of the comparison on the technical condition of the receiving channel, wherein the receiving trakcie, determine the integral value of the absolute values of the output voltages of the channels receive path, which is used as informative parameters, determine the arithmetic average value of informative parameters, which are used as reference values.2. The method according to p. 1, characterized in that the reference value is remembered and used in the comparison of informative parameters.
SUBSTANCE: the method consists in determination of lots with a reduced percentage of yield of satisfactory products after each check operation. The dominant type of reject of products of the given lot is revealed, the scope of additional rejection tests is determined, and total additional rejection tests are carried out. After the additional tests the lot is returned to the initial check operation.
EFFECT: ensured production of lots with a guaranteed value of reliability.