Some standard content:
Er.Ss 33.140
National Standard of the People's Republic of China
GB/T 3241--1998
eqv IEC 1260:1995
Octave-band and fractional-octave-band filters
Octave-band and fractional-octave-band filters1998-04-10Issued
Implementation on 1998-12-01
Issued by the State Administration of Quality and Technical Supervision
GB/T 3241:-1998
EC Foreword
2 Referenced standards
3 Definitions
4 Performance requirements
5 Test methods
6 Device marking only
User Manual
Appendix A (Appendix of the Recommended System)
Appendix (Appendix of the Recommended System)
Appendix A (Appendix of the Recommended System)
Center frequency of the band
For 1/3 times the relative value of the normalized compliance band at the small and large relative value limits, recommended items for the electrical characteristics test of the device+
GB/T3241:1998
This standard is based on the International Electrotechnical Commission The standard of the 1995 edition is C1260:1995. This standard is equivalent to GB321824, which adopts 1 gate and 1/3 protection filter. The writing format and rules of this standard follow the GB/T1.119934 standardization work guidelines, Part 1, basic provisions for standard writing and the general provisions of the first amendment. This standard replaces G3241-82 from the date of entry into force. Appendix A, Appendix B and Appendix C of this standard are all informative appendices. This standard was proposed by the Ministry of Electronics Industry of the People's Republic of China. This standard was prepared by the National Acoustic Equipment Standardization Technical Committee. The technical standard drafting units are Nanjing University and the Institute of Acoustics of the Chinese Academy of Sciences. The main drafters of this standard are Zhao Qi and Zhang Rucheng. "Unit 1, Drafting and Preparation of Standards
GB/T3241-996
IEC Foreword
1) IEC: (International Electrical and Electronics Standardization Committee) is a world-class standardization organization composed of members of all national electrical and electronic induction conferences. It is an international conference for all major issues related to standardization in the field of electrical and electronic induction. In addition to other appropriate activities, IEC finally publishes national standards. Their formulation is entrusted to technical committees. Any country that is interested in the subjects involved may participate in the work. FC has established relations with the country 1) All national committees and technical committees of the International Organization for Standardization (IOS) on the same subject matter shall work closely together to establish technical specifications. 2) All national committees and technical committees of the International Organization for Standardization (IOS) on the same subject matter shall have the right to reach an agreement on the relevant technical specifications in the form of standards, technical reports or guidelines, which shall be used internationally and in this sense shall be the sole responsibility of the Member States. 5) These agreements or arrangements shall be made in the form of standards, technical reports or guidelines, which shall be used internationally in the form of recommendations and in this sense shall be the responsibility of the Member States. Acceptable.
1) In order to reduce the number of international standards, EC National Committees shall adopt the official EC standards in their national or regional standards within the maximum possible range. Any inconsistency between IEC standards and corresponding national or regional standards shall be indicated in the text. \) F does not provide a specific procedure for its certification. For any claim that the value of its standards is not the same as that of the international standard IEC2eC for electroacoustics, this standard is published in 1966. The text of the standard is based on the following documents: 29/292/IHS. The voting information of the standard is shown in the table above. To Appendix A, Appendix and Appendix (for information only) Voting report 29/3J4/RVIH 1 Scope National Standard of the People's Republic of China Octave-band and fractional-octave filters Qetave-had mnd Fractional actnve btund tilters GB/T 32411998
eq1E4:1760.1995
code372192
1.1 This standard specifies the performance requirements for the analog, sampled, and digitally acquired passband components of filters or amplifiers. For all filters of a given bandwidth, the passband range determined by the filter characteristics is a given fraction of the center frequency. Instruments meeting the requirements of this standard may include filters with any desired frequency range and a maximum signal count of 1. .2 This standard gives the performance requirements for three levels of isolators, level 0, level 1 and level 2, with the tolerance increasing as the level increases. 1.3 The isolators that meet the requirements of this standard can be part of various measurement systems or an integral part of a certain instrument, and can be used in conjunction with the instrument. 1.4 The instruments that meet the requirements of this standard can provide the desired harmonic signal for various signal conditions, such as time-varying, intermittent noise, broadband and discrete frequency signals, and signals of long duration and short duration. The isolators of this type that meet the requirements of this standard may give different results in applications involving other signals. 2 Referenced standards The following standards contain documents that constitute the provisions of this standard by reference in this document. The versions shown are valid at the time of publication of this standard. All standards will be revised, and the parties involved in this standard may discuss and use the latest versions of the following standards. GB334n82 Acoustic measurement of constant frequency GB/T13326.2-92 Industry requirements for measurement and control of electrical and electronic equipment for fuel combustion compatibility GB/T13926.3-92 Industry requirements for measurement and control of electromagnetic fields of passenger vehicles 3 Definitions This standard is related to the following definitions 3.1 Passive wave The device te
has only one transmission band (or a device with a small attenuation of the near-attenuation), which extends from the lower limit frequency to the upper limit frequency.
3.2 times the octaveA
The nominal frequency ratio is 2:1: denoted as C.
1When determining the ratio of the octave band of the dynamic signal bottle, this standard allows a choice of light, when the change is less than 10 and less than 2.2For the system with 1 as the crown,
For the system with 2 as the shore1
G: = 2
Three accounts choose the remaining system with 16 as the court,
3:3The band refers to the card value la:mlwil. n rdexig1iturState Administration of Quality and Technical Supervision19980410Approved 2
1998-12-01Implementation
GB/3241—1998
The reciprocal of a positive integer in parentheses is used to indicate the fraction of the octave bandwidth, denoted as 1/b, 3.4 Reference frequencyreferencefrenuency
The exact value is 1000Hz. Note:bzxZ.net
3.5 Exact midbandfreyuency is the frequency that has a regular relationship with the reference frequency, which makes the ratio of the exact center frequencies of any two adjacent bandpass filters in a specified bandwidth filter group, denoted as, with the unit being H. When the bandwidth indicator value is divided by the required number, the accurate center frequency of any full filter in the filter is determined by the following formula: C. +: (erytf
When the denominator of the bandwidth indicator value is the required number. The accurate center frequency of any filter in the group is determined by the following formula: fh -- (G'a-1yef.)
Formula, a
any sufficient number, positive or negative or
1The accurate center frequency of the filter determined by formula (3) or (4) is the filter limit. It is allowed to estimate the efficiency of the corresponding lithium source filter combination. The filter can produce a filter with an accurate center frequency of the cabinet. The filter level is determined by the total efficiency of the filter. With a chain of 10, any "10:1 ratio or the average load ratio included in the figure" "Any other 1℃!1 measurement frequency range should be the center number of this rod. Except for the different positions of the small teaching symbol, the total number is the village company. The actual center frequency is a single, non-repeating 3 examples of lights, with a 1/3 times original filter, the nominal center frequency is 55X5H. The correct center frequency (not counting the three letters) is 511.872Hz in the base 10 system and 5039.684H in the base 2 system. The difference between the two is nearly 0.%, when the core center is 50H, in a system with a base frequency of 1, it is 5011%723, in a system with a base frequency of 2, it is 50796.3H, the lower of the two is approximately 1.4%,
When the denominator of the actual value is small, there will be a core part in the complete source group with a center frequency of 1600H. When the denominator of the bandwidth indicator is the modulation number, in the complete filter such as CCH, there is a center period of one Hz for the filter,
The accurate center frequency of the filter must be drawn in the installation, 3.6 grid bottle Wei》center frequencynomiaalmidbandfrequcncyTake the integer of the center frequency and use it to represent the bandpass filter, the unit is Hz, 3.? The bandedgefrequence is the lower and upper frequency limits of the passband of the filter, in z. After the lower and upper cutoff frequencies are determined (respectively, and the geometric assumptions of the cutoff frequency are correct), the cutoff frequency is given by the following formula: f, (G-->(f)
F, -r+rf.
where: the order ratio is calculated by formula (7) for systems with base 1 and by formula (2) for systems with base 2; f - the exact center frequency determined by formula (3) or (1). 3.8 Normalized rate Frequently: For a bandpass filter, the ratio of the frequency to the center frequency is expressed as: 39 The bandwidth of the filter is fiiterbundwidth(5)
For a given filter, its upper limit frequency minus the corresponding lower limit, and ": are calculated using equations (5) and (6) respectively. 3.10-octave bandpass filter with a ratio of 2 between the frequency limit and the lower limit frequency: 3-T fractional-band filter tractionaiactRve-band ftlter is a kind of bandpass filter. It sets the upper limit frequency, and the ratio of the lower limit frequency f is a certain ratio. The bandwidth index is equal to the corresponding bandwidth index. Note: It is expressed by the number 2. The overload rate is 2.12.11im.11im.11tt.1GD/T32411998 ... cl
select the time to select the film number, only the two numbers of time: T--corresponding to the time
corresponding to the relative position of the output signal. 3.13 Multiple consideration reercealteuaion
In order to determine the old quality of all the filter filters of the instrument, the manufacturer specifies the reduction of the nominal filter filter in the usual range, the unit is minutes, as-
3. 14 Scan r-lit al
For oil you Di device, let any rate, however, the wave coupons of my reduced source cloud if you like, the unit is m. Note: in the rate single do points! , sure:
t in: A!
In the pure production city of chemical smoothness,
small one consider secretion.
Accurate central interest rate,:
3.15H one effective band feel narma.ixedaeivebandidthte
sexuality in the appropriate amplitude of the upper string electric auxiliary input The signal, the ratio of the time mean square value of the signal indicated by the readout of the waveband input signal to the initial input signal, can be calculated by integrating the time mean square value of the signal multiplied by the constant 1-1, where A is the parameter step reduction, and the single-generation is denoted as 6. Note: The effective bandwidth is analyzed to give F1.-2, and the information in Section 3.16 is ncmrlizedreferancebandwidth for the waveband, the ratio of the shallow band to the center of the standard new reception, and is also denoted as. Net: The following formula determines the middle dragon base control band: Be
_G+!s, .- G---
3.1 method! 9
The ratio of the H side effect of the law wave to the normalized H standard bandwidth is 10 as the logarithm of the home, multiplied by 10, the unit is decibel, the word is: teach the table to play the big heart cattle to reason
3.18 Winter test self-standard flrung
For the test convex performance, the manufacturer has no fixed level range, the unit is decibel, 3.79 More cats test signal electric returunceirputzigzal Jevel in more self-trapped, manufacturing! The signal of the program is repeatedly, the unit is decibel. 3.20 The level difference
The output signal level minus the input signal level plus the level range controller range nominal I minus! If there is any), use the section! 3.21 The relative humidity of the input signal at the center frequency is within the specified range for the input signal. For the used input signal, the unit is 3.22 The relative humidity of the input signal at the center frequency is within the specified range for the input signal. The unit is 3.23 The linear operating range is linceruperairgrEnRc. For the specified range of levels, the linearity of the level is maintained within the specified tolerance from the lower limit to the upper limit. When the sinusoidal input signal is also within the specified range, the unit is 3.24 The linear operating range is linceruperairgrEnRc. For the specified range of levels, the linearity of the level is maintained within the specified tolerance from the lower limit to the upper limit. 3.24 Level range control: A device used to adjust the sensitivity of the instrument to adapt to changes in the input signal in order to ensure that the instrument operates within the specified range. 3.25 Containment range: For any nominal center frequency, the upper limit of the input signal level within the minimum sensitivity range is reduced to the lower limit of the input signal level within the maximum sensitivity level range. 3.26 Analog filter: A filter that continuously operates on the input signal to produce a continuous output. 3.27 Sampled-data filter: A computational process that samples the input signal and produces a continuous output. 3.28 Digital oscillator A method of filtering sampled data by digitizing the sampled data. 3.29 Real-time operation A method of filtering sampled data by digitizing the sampled data. The method produces a low-pass filtered output signal and the time required to perform the calculations, averaging, and other calculations associated with the bandpass filter is less than the sampling interval of the sampled data within the sampling interval, so that all samples of the input signal are equivalent to the resultant filtered output signal. 3.30 Aliasing Prediction A method of filtering sampled data by aliasing frequency corners. It is caused by the sampling of a continuously changing input signal at a rate lower than the high frequency component of the input signal. 3.31 Anti-aliasing filter A low-pass filter used to reduce the energy consumption component in the output current to a negligible level 4 Performance requirements
4.1 General
The electrical response characteristics of fractional octave filters specified in this standard apply under the conditions of 4.13. Any fractional octave ratio of 1 or 2 may be used provided that it meets all the applicable requirements of this standard.
4.2 The nominal (band) center frequency
is the appropriate value of the exact center frequency used to test or calibrate 1/2- and 1/4-band filters. Appendix A provides the exact center frequency and nominal center frequency for 1/4- and 1/2-band filters. The procedure for determining the nominal center frequency required for the filter passband is given. 4.3 The manufacturer shall specify the reference frequency within the passband. This frequency shall be the same for all filters in a group of filters. 4.4 Phase reduction
4.4.1 For 0, 1 or 2-band filters, the respective attenuation of all frequencies shall be within the specified values. Table 4.4 gives the minimum and maximum values for the specified normalized frequency within the bandwidth.2 The fractional octave filter with a bandwidth indication of 1/, for the screening level, the cabinet should be at a finite relative reduction limit, 0, the normalized rate of the complete end of the fractional bandwidth: calculated as follows: u + [tG/(r
-++++++(10 3
GB/T 3241—1998
1, the lower end of the fractional frequency bandwidth can also be normalized to the frequency 1 using the following formula: 0.-1/b
has the same limit on relative attenuation.
, Appendix and provides the 1/3 drop period egg wave band at the normalized frequency point. If the amount of the relative reduction is small according to the single measurement of the person, but the single measurement of 4.4.3 for the compensation process of the short wave filter, the normalized rate 2 given in Table 1, the advantage is to select the end of the integer multiple of the monkey 10) or 1) formula and make the ratio of the normalized fractional multiple of the whole frequency between the complete frequency, in the mountain frequency single, the necessary competitive reduction limit 1 order should be determined by the continuous insertion relationship,
2A,-4A,[4An 2A[g(/,)/lg/,]
Wherein: AA,
at the normalized frequency 2, the average relative loss value, 4, at the normalized frequency 0, the relative loss value of the filter is the minimum value: the maximum loss limit
white: the maximum loss limit
t. 15 +y. 15
4. 151 —9. 2
± 15, —0. 1
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+75 —
regular waveguide
0.S, +c.3
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*At frequencies below the lower limit and below the desired rate, the maximum relative standard deviation is -1.12
: 0. 5: -3. 5
0. 5: --3. 6
- 0. 5; --3. 9
--G. 5; -- 1. G
-c. —:. s
+1- t+ .
+ss +m
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4.4.4 Figure 1 shows the minimum and maximum relative height reduction limits for multiple-pass filtering. Figure 1 also shows the continuous change in attenuation of the small sample at the load point and the significant change in attenuation of the sample between two normalized points in the graph. 2rE
GB/T 3241—1998
Maximum limit
Maximum positive value
Frequency factor F (for scattered moments):
Figure 11 Explanation of the minimum and maximum attenuation limits of the relative attenuation of the level 11 double frequency wave shield 4.5 Filter integral integral should
4.5.1 For the filter with filter mark, the integral of the filter should be 8. The single busy is decibel, and it is determined by the following test: BF = 10g(R/.)
Where: B, normalized effective bandwidth
B—the normalized reference bandwidth obtained by the () formula. 4.5.2 For any filter with an exact center frequency of, the normalized effective bandwidth is expressed as; B.
Where: 2A(F/f.)-
o wadufr)
is the relative response of the filter in units of decibels. In practice, the integral in (14) is a numerical estimate, first 5. 4.
1.5.3 For each of the two passband filters, the filter decibels of 0.1 and 2 are only effective at 0.1H, ±.3 dB and ±6 dB.
4.6 Linear operating range
4.6.1 For all filter bandwidths, and for all power supplies (if applicable), the linearity error within the operating range for Class 0, 1 and 2 filters shall not exceed ±0.3dB, ±0.48 and ±0.5dB respectively. Their linear operating ranges shall be at least BdB and 4UB respectively. 4.6.2 If an additional linear range is provided, the linearity error for Class 1 filters shall be at least 40% for Class 1 filters and at least 6% for Class 3 filters. 32411998
4.6.3, when using color, the method of setting the half-range of the electrical explosion: if it is not within the starting level range, it is allowed to reduce the line energy operating range in the most sensitive range,
4.6.4 For the filter that displays the full aperture, or when the output of the wave concentrater is sent to an external display, or to other systems, and the display range is expanded by the user, then the manufacturer shall specify the linearity of the level maintained outside the load range. 4. For real-time work
the manufacturer shall state the bandwidth indication value and the corresponding standard range. Within this range, the corresponding ten-point loss medicine stops the input signal. The output rate of the reporting signal changes at a certain ratio. For the core grade 1 receiver, the theoretical output multiple is within 3B, and for the grade 2 double data, it is within 0.5B. The theoretical input signal level expression for a constant amplitude swept sinusoidal input signal is given in 5.5.
4.8 Anti-aliasing Filters
In a sampled data or digital filter system, the components include appropriate analog and digital anti-aliasing filters. The anti-aliasing filter component minimizes the interference between the input signal and the sampling process, because the sampling point will produce aliasing of the input signal and the filtering required should exceed the minimum limit given in Table 1. 4.9 The signal level of the input signal shall be zero, and the difference between (a) and (b) for the level 1 and level 2 devices shall not exceed 1.0, 1.0, -2.0, 4.0, 4.10, respectively. The level of the output signal shall not exceed 1.0, 1.0, -2.0, 4.0, 4.10, respectively. The level of the output signal shall not exceed 1.0, 1.0, -2.0, 4.0, 4.10, respectively. The level of the output signal shall not exceed 1.0, 1.0, -2.0, 4.0, 4.10, respectively. The level of the output signal shall not exceed 1.0, 1.0, -2.0, 4.0, 4.10, respectively. The level of the output signal shall not exceed 1.0, 1.0, -2.0, 4.0, 4.10, respectively. The level of the output signal shall not exceed 1.0, 1.0, -2.0, 4.0, 4.10, respectively. The level of the output signal shall not exceed 1.0, 1.0, -2.0, 4.0, 4.10, respectively. The level of the output signal shall not exceed 1.0, 1.0, -2.0, 4.0, 4.10, respectively. : The maximum mean square voltage of the sinusoidal input signal in the range of one level shall be within the range of the use level. Each filter in the device shall meet the requirements of this standard. 4.12 The impedance of the device shall be guaranteed to be greater than the impedance of the output terminal when the device is working normally. 4.13 Standard environmental conditions The basic environmental conditions include an atmospheric temperature of 27°C, a relative humidity of 65%, and an atmospheric pressure of 101.3 kPa. 4.4 Sensitivity to various environmental conditions 4.14.1 Atmospheric temperature Within the range of 10°C to 10°C, the relative humidity of any filter in the device shall be less than 0.15 dB, = 0.3dH and Io.n at the same frequency point under the reference system. For level 1 and level 2 instruments, the relative humidity shall be less than 0.15 dB, = 0.3dH and Io.n respectively. d3.
The manufacturer shall indicate that the instrument can continuously work within the range of relative humidity and the corresponding atmospheric temperature. The instrument shall be exposed to an atmosphere of relative humidity of 4°C and the components within the instrument shall be subjected to the condition of minimum cold load. After 24 hours, the filter shall be swept at the nominal center of the instrument. The relative frequency of the excitation point at the same frequency as the 1 and 2 instruments shall be ±2.1°C, ±3°C and ±5°C respectively. 4.14.3 The magnetic field
shall be reduced as much as possible (to minimize the effect of the alternating current at the frequency of the two inductors). 4.14.4 Static current
The effect of static discharge on the full-wave filter should be minimized as much as possible. ?
4.14.5 High-frequency electric field
GB/T3241—1998
The influence of radio frequency electric field on the filter group should be minimized as much as possible. 4.15 Power supply control
For instruments that need to use electricity as power supply, a method should be provided to continuously check whether the power supply is sufficient. During the calibration period, the calibration should be carried out in accordance with all the requirements specified in this standard. 5 Test method
5.1 General
The test methods described in this chapter may be used for type assessment or periodic verification to determine whether the performance of the overall device remains within the tolerances specified in Chapter 4. The manufacturer may recommend other tests to replace the methods described in Chapter 5 to verify compliance with the requirements of this standard. The test methods recommended in Appendix C may be used for type assessment or periodic verification. All test results shall be in accordance with the reference environmental conditions of 4.13. The receiver under test shall be connected to the power supply and placed in the conducting position before the test is started. Preheat for the time specified by the manufacturer.
5.2 Test equipment
5.2.1 In order to verify that all results meet the requirements of Chapter 4, a steady-state excitation signal with a single frequency and signal level shall be used in addition to the real-time working frequency limit test. For the test to determine the rated frequency limit of real-time operation, a constant sinusoidal signal is used. It is temporarily collected at a logarithmic rate, or the bandwidth is shown. In order to test the relative attenuation of all data filters in the instrument, the bandwidth is shown. The signal generator or signal source should be able to produce a sinusoidal test signal within the required test frequency range. Note: The test formula is given by the formula (15): 5.2.2 The measurement level used for the test is that at any frequency, the total distortion of the positive signal output by the signal generator, including the imaginary component, should not exceed 0.01. The accuracy of the sinusoidal test frequency should be within ± 9.01% of the indicated frequency. 5.2.3 The micro-sine test signal level should be able to vary within the range of at least 80dB. 5.2.4 For bandpass filters designed to the requirements of the sound level meter for use in the test device, the display indicator shall be used to measure the output signal level of the filter group. 5.2.5 For filter groups with digital readout or with a digital format specified by the manufacturer (e.g. digital interface), the output level shall be determined by digital readout or via digital output to a suitable recording device. 5.2.6 For tests of real-time operation, the output level of the signal transmitter shall be centered and shall remain constant within the selected range corresponding to the nominal center frequency to within ±0.2 of the nominal signal level. After the sweep is completed, the sensitivity of the test signal to the frequency range shall be maintained within ±1% of the starting sweep frequency. 5.3 Relative variation
5.3.1 The relative attenuation characteristics of each filter in the filter bank shall be measured within the reference level range. The input signal level shall be 1H above the upper limit of the linear operating range.
5.3.2 Apply a steady-state sinusoidal signal to the auxiliary terminals of the filter bank and measure the input and output signal voltages at appropriate frequencies. Note: When necessary, the auxiliary input and output of the instrument shall be connected within the national regulations. 5.3.3 For the type-extension evaluation test, the test signal (the difference between the input and output signal levels) shall be a programmable device automatically controlled to evaluate the performance of the filter. The sinusoidal test signal shall be preferably discrete frequency points, which are equally spaced in the logarithmic coordinates of the center frequency before adjustment. If 5 is the number of test frequencies obtained by the instrument room, then the normalized formula after the first test is [Gw
...(15
, 1 integer or negative integer, including data, etc., the test frequency number S of each filter bandwidth is not less than 24. When the ratio of the key frequency is reduced or increased, the test frequency of each filter bandwidth will be greater than 24 points. The number of new test frequencies added by the industry should be considered as a step, and the integral response of the scoring filter is not related to 5, so the error caused is near.
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