GB/T 11313-1996 Radio frequency connectors Part 1: General specification General requirements and test methods
Some standard content:
GB/T 11313-1996
This standard is equivalent to IEC1169-1:1992 "Radio Frequency Connectors - Part 1: General Specifications" This standard makes the following amendments and supplements to the content of IEC1169-1:1992: 1) The comparison table of corresponding clauses of IEC169-1 and IEC1169-1 is deleted. General requirements and test methods
2) The three standards IEC68-2-18, IEC68-2-52 and IEC803 that were originally omitted are supplemented in "3 Reference Standards". 3) In the fourth paragraph of "9.1 Overview", "The group test table is shown in Appendix A." is changed to "The group test table is shown in 10.3.2.3". 4) In "9.1.2 Appearance Inspection", "The marking shall comply with the provisions of 11.2." is changed to "The marking shall comply with the provisions of 11.2." ” is changed to “The marking shall comply with the provisions of 11.1”. 5) Change “9.2.1.7.2 The error-free identification method in accordance with 9.2.1.1” to 9.2.1.7, 2 The error-free identification method in accordance with 9.2.1.4 and 9.2.1.5”. 6) Change \9.2.1.7.3 The error identification method in accordance with 9.2.1.4” to *9.2.1.7.3 The error identification method in accordance with 9.2.1.6”.
The above amendments and supplements do not affect the equivalence of this standard with IEC1169-1. Products produced in accordance with the provisions of this standard can directly enter the international market and can be used and interchangeable with similar international products. Appendix A and Appendix B of this standard are the appendices of the standard. This standard is proposed by the Ministry of Electronics Industry of the People's Republic of China. This standard is under the jurisdiction of the National Technical Committee for Standardization of High-frequency Cables and Radio Frequency Connectors for Electronic Equipment. This standard was drafted by the Standardization and Promotion Institute of the Ministry of Electronics Industry. The main drafters of this standard are Wu Zhengping, Xu Lidi and Chen Tianhua. 253
GB/T11313-1996
IEC Foreword
1) The formal resolutions or agreements of IEC (International Electrotechnical Commission) on technical issues are formulated by technical committees in which national committees with special concerns about these issues participate, and represent the international consensus on the issues involved as much as possible. 2) These resolutions or agreements are in the form of recommended standards for international use and are recognized by national committees in this sense. 3) In order to promote international unification, IEC hopes that national committees will adopt the text of IEC standards as their national standards when national conditions permit. The differences between IEC standards and corresponding national standards should be indicated in national standards as much as possible. 4) IEC has not established any procedures for the use of recognition marks, and IEC is not responsible when a product is declared to comply with the corresponding IEC standards.
This standard was prepared by Subcommittee 46D (Connectors for Radio Frequency Cables) of IEC Technical Committee 46 (Cables, Wires, Waveguides, Connectors and Accessories for Communication Equipment and Signals). This standard text is based on the following documents: IEC169-1, IEC169-1-1, IEC169-1-3, and the following documents: Six-month method 46D(CO)107 46D(CO)122 46D(CO)135 46D(CO)136 46D(CO)145 46D(CO)147 46D(CO)158 Voting report t||46D(CO)129
46D(CO)132
46D(CO)151A
46D(CO)155
46D(CO)169
46D(CO)170
46D(CO)187
Two-month method
46D(CO)140
46D(CO)183
Detailed information on voting and approval of this standard can be found in the voting report listed in the table above. The QC number on the cover of this standard is the standard number of the IEC electronic component quality assessment system (IECQ). 254
Voting report
46D(CO)152
46D(CO)202
1 Scope
National Standard of the People's Republic of China
Radio-frequency connectors-
Part 1: Generic specificationGeneral requirements and measuring methods This standard specifies connectors for radio-frequency transmission lines in communications, electronic equipment and similar equipment. 2 Purpose
GB/T 11313
idt IEC 1169-1:1992
QC220000
Replaces GB11313-89
This standard, as a general specification, is the basis for the formulation of sub-specifications for each connector. Its purpose is to specify unified concepts and procedures for the following contents. Terminology;
Standard ratings and characteristics;
Test and measurement procedures for electrical and mechanical properties; Connector categories classified by environmental test procedures for temperature, humidity and vibration. The test methods and procedures in this standard are applicable to type approval tests and their recognition. This standard can also serve as the basis for acceptance tests when the manufacturer and the user agree.
3 Cited standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. IEC27 Letter symbols for electrotechnical use
IEC50 International Electrotechnical Vocabulary (IEV)
IEC50(151):1978 Electromagnetic devices
IEC68-1:1988 Environmental testing - Part 1: General and guidelinesIEC68-2-1:1990 Environmental testing - Part 2: Various tests - Test A: Cold (low temperature)
IEC 68-2-2:1974
IEC 68-2-3:1969
Environmental testing - Test B: Dry heat (high temperature) Environmental testing - Test Ca: Steady-state damp heatIEC 68-2-6:1982E
Environmental testing - Test Fc and guidelines: Sinusoidal vibrationIEC 68-2-11:1981
Environmental testing - Test Ka: Salt spray
IEC68-2-13:1983Environmental testing - Test M: Low pressureIEC68-2-14:1984Environmental testing - Test N: Temperature changeIEC 68-2-17:1978
Environmental testing
IEC 68-2-18:1989
Environmental testing
Test Q: Sealing
- Test R and guidance: Water
Approved by the State Administration of Technical Supervision on November 12, 1996 and implemented on October 1, 1997
IEC 68-2-20:1979
IEC 68-2-27:1987
IEC 68-2-29:1987
IEC 68-2-30:1980
Environmental testing
GB/T 11313-—1996
Test T: Soldering
Environmental testing - Test Ea and guidance for shock
Environmental testing
Environmental testing
Test Eb and guidance for collision
Test Db and guidance for damp heat, cyclic ((12+12)h cycle)IEC 68-2-42:1980
Test Kc: Sulfur dioxide test for contacts and connectors Environmental testing -
IEC68-2-47:1982 Environmental testing -
- Installation of components, equipment and other products for dynamic testing IEC68-2-52 Environmental testing - Test Kb: Alternating salt spray IEC68-2-54:1985 Environmental testing - Test Ta: Wetting weighing method Solderability test IEC457-1:1974 Rigid precision coaxial cable and related precision connectors - Part 1: General requirements and test methods IEC617 Graphical symbols for drawings
IEC803 Hexagonal and square die-cast cavities, press heads, standard gauges, outer conductor crimp sleeves and center contacts for radio frequency cables and connectors Crimping wire dimensions
ISO370:1975 Tolerance size: conversion between inches and millimeters ISO1000:1981 Recommendation for the use of the International System of Units (SI) and its multiples and certain other units 4 Definitions
The following definitions apply to this standard.
4.1 General vocabulary of connector parts
4.1.1 (Electrical) contact (electrical) contact Individual conductive parts are in close mechanical contact and can provide a low resistance path for current in both directions. 4.1.2 Contact
Conductive part in a component that is inserted into a corresponding conductive part to provide an electrical path (provide electrical contact). 4.1.3 Male contact
Pin contact
Contact part that can be inserted into a female (socket) contact to form an electrical contact on its outer surface. 4.1.4 Female contact
Socket contact
Contact part that can accept the insertion of a male (pin) contact to form an electrical contact on its inner surface. 4.1.5 Hermaphroditic contact A contact that can be mated with a contact that is equivalent to itself. 4.1.6 Resilient contact A resilient contact that can exert pressure on mating parts. 4.2 Basic vocabulary of connectors
4.2.1 Connector
A separable component (except adapters) that is usually installed on cables or equipment for electrical connection of transmission line systems. 4.2.2 Connector pair
Two connectors with complementary mating surfaces and locking mechanisms that can be mated and interlocked. 4.2.3 Type
Series
A term that characterizes the specific mating surfaces and locking mechanisms of a connector pair related to structure and size. Note: The term "series" is sometimes used to refer to the general term for all connector varieties with the same mating surfaces and locking mechanisms, and is a close synonym to "type". 4.2.4 Style
indicates the specific form, shape and combination of connectors of the same type, for example, free-end connectors and fixed connectors, straight connectors and 256
angle connectors, and straight and right-angle adapters of the same type. GB/T 11313—1996
Note: *The term "adapter" is given in 4.5.1 to 4.5.5. Adapters of the same type can also be regarded as a specific variety of a given type. 4.2.5 Specification variant
Indicates the change in specific details of the variety, such as the change in the size of the cable entry. 4.2.6 Grade
The level of mechanical and electrical precision of the connector, especially the specified reflection coefficient. 4.2.7 General purpose connector (Grade 2) general purpose connector: Grade 2 is a connector manufactured with the widest allowable dimensional deviation (tolerance), but still able to ensure the minimum specified performance and intermateability. Note: The requirements for reflection coefficient may or may not be specified. 4.2.8 High performance connector (Grade 1) high performance connector: Grade 1 A connector that specifies the reflection coefficient limit value according to the frequency change. The dimensional tolerances specified are usually not stricter than those of the corresponding Class 2 connectors. However, when it is necessary to ensure that the connector meets the reflection coefficient requirements, the manufacturer has the responsibility to choose a stricter tolerance. 4.2.9 Standard test connector (Grade 0) standardtestconnector: Grade 0 A precision-made specific type of connector used to measure the reflection coefficient of Class 1 and Class 2 connectors, and the error caused by the measurement result can be ignored.
Note: The standard test connector is usually part of the adapter between different types, and the adapter is connected to the precision connector to form part of the test equipment. 4.2.10 Precision connector precision connector has a mechanically and electrically coincident reference surface, air medium, and can form highly reproducible connection characteristics without obvious reflection, loss or leakage. Precision connectors are intended to be installed on air transmission lines and instruments. According to IEC457-1, precision connectors can be non-polar, flange or pin and socket types. 4.2.11 Laboratory precision connector (LPC) laboratoryprecision connector (LPC) A precision connector with no dielectric support for the center conductor. 4.2.12 General precision connector (GPC) A precision connector with dielectric support for the center conductor, which can support the center conductor of a laboratory precision connector without dielectric support and mate with a standard air transmission line.
4.3 Structural vocabulary
4.3.1 Male connector
Pin connector
A connector with a male (pin) center contact. 4.3.2 Female connector Female connector Socket connector
A connector with a female (socket) center contact. 4.3.3 Plug connector Plug connector A connector with an active part of the connection mechanism (connection nut or bayonet ring), usually a free-end connector. Note: Depending on the specific type, a plug can be a male connector or a female connector. 4.3.4 Socket
A connector that mates with a plug.
4.3.5 Hermaphroditic connector A connector that can be mated with a connector that is equivalent to itself. Note: The connection (locking) mechanism is not necessarily non-polar. 4.3.6 Free-end connector A connector that is attached to the free end of a cable, usually a plug. Note: If it is not specified as fixed, the connector is a free-end connector. 257
4.3.7 Fixed connector GB/T 11313--1996
A connector with a mounting mechanism fixed to the mounting surface, usually a socket. 4.3.8 Triaxial
A transmission line consisting of three layers of core conductors with a common axis and insulated from each other. 4.4 Sealed
4.4.1 Sealed connector A connector that meets the specified gas, moisture or liquid sealing requirements. 4.4.2 Barrier seal
A seal that prevents gas, moisture or liquid from entering the interior of a connector housing in the axial direction. 4.4.3 Panel seal
A seal that prevents gas, moisture or liquid from entering the fixed connector or adapter housing and the panel through the mounting hole. Note: Seals are usually provided as separate products. 4.4.4 Mating face seal A seal that prevents gas, moisture or liquid from entering the interface of a pair of mating connectors. 4.4.5 Hermetic seal
A seal that meets the requirements specified in test Qk of IEC68-2-17. 4.5 Other vocabulary and related measurement equipment vocabulary 4.5.1 Adaptor
A two-port device that connects two transmission lines with connectors that cannot be directly mated. 4.5.2 Fixed adaptor An adaptor with a mounting member fixed to the mounting surface. Note: If not specified as fixed, the adaptor is a free-end adaptor. 4.5.3 Within-type adapter An adapter used between two or more connectors of the same type. 4.5.4 Inter-type adapter An adapter used between two or more connectors of different types. 4.5.5 Standard test adapter An adapter used for testing, one end of which is a standard test connector and the other end is a precision connector. 4.5.6 Standard air line A uniform air dielectric transmission line with the smallest possible conductor diameter and straightness errors, no dielectric support for the inner conductor, and a non-magnetic material with good electrical conductivity. www.bzxz.net
4.5.7 Reference line An air transmission line similar to the standard air transmission line, but with dielectric support for the inner conductor and designed to maintain the minimum internal reflection coefficient within the frequency range used for measurement.
4.5.8 Cable simulator cablesimulator a precision transmission line with accurate characteristic impedance, usually a precision cable. The connector under test shall be so mounted that the transition from the coaxial line to the connector simulates as accurately as possible the normal state of the connector when mounted on an appropriate cable (particularly with regard to reflection coefficient and impedance interference).
4.5.9 proof coupling torque
the maximum torque applied to a threaded connection of a particular connector series to test the mechanical strength of the connection. 4.5.10 normal coupling torque the maximum and minimum torque values to be applied to connect a threaded connector in the normal manner 4.5.11 engagement and separation torque258
GB/T 11313--1996
the torque required to overcome friction, spring pressure, etc., during the engagement and separation of a connector with a rotary connection before or after full engagement. It is used to check for overtightening of threads, burrs on bayonet mechanisms, degree of rotational freedom of connecting rings, etc. 4.6 General electrotechnical vocabulary
Note: The following vocabulary and definitions are quoted from 151-04-01, 151-04-02 and 151-0403 of Chapter 151 "Electromagnetic Devices" of IEC50 (151) (1978) International Electrotechnical Vocabulary. The note added in 4.6.1 "Nominal value" is for use in this specification. 4.6.1 Nominal value
A suitable approximate value used to mark or identify a component, device or equipment. Note: By definition, the nominal value has no tolerance. 4.6.2 Limiting value
The maximum or minimum value allowed in the specification. 4.6.3 Rated value
The value of a component, device or equipment under specified working conditions usually given by the manufacturer. 5 Units, symbols and dimensions
5.1 Units and symbols
Units, graphic symbols, text symbols and terms shall be selected from the following standards as far as possible: IEC27 Alphabetic symbols for electrotechnical use
IEC50 International Electrotechnical Vocabulary (IEV)
IEC617 Graphical symbols for drawing
ISO1000 (1981) Recommendations for the use of the International System of Units (SI) and its multiple units and certain other units. 5.2 Dimensions
5.2.1 Details to be specified in relevant specifications
Each relevant specification shall specify:
i) Sufficient dimensional data of the mating surfaces of universal connectors and standard test connectors to ensure intermateability and meet performance requirements; when a crimping die is used, its dimensions shall be in accordance with the provisions of IEC803; i) The maximum external dimensions of the connector that the user can install the connector into the equipment. The primary purpose of the drawing is to ensure mechanical interchangeability and adequate electrical performance. Therefore, no restrictions are imposed on structural details that do not affect interchangeability and performance requirements, nor should they be used as manufacturing drawings. Note: Equipment designers should study the limits marked on the outline drawing rather than the dimensions of individual samples. 5.2.2 Dimensional units used in the specification
Dimensions and tolerances shall be given in both millimeters (mm) and inches (in), and the original system of units shall be stated. The highest accuracy required for various dimensions that are independent of the system of units shall be such values that the first digit shall not exceed five digits when it is 1 or 2, and the first digit shall not exceed four significant digits when it is 3 to 9. In any case, the accuracy shall be limited to 1 μm or 0.00005 in.
5.2.3 Conversion between inch and millimeter dimensions In principle, the dimension conversion process should be rounded to the nearest 0.001 mm or 0.00005 in. However, when mechanical and electrical considerations permit, they should normally be rounded to the nearest 0.01 mm or 0.0005 in. The above requirements also apply to conversions between systems of units after accurate calculations have been made in accordance with ISO Standard 370 "Tolerances of Inches to Millimeters". The following note should be added to each specification reading: "According to ISO 370 "Tolerances of Inches to Millimeters", the dimensions in *.* converted from those in *." may not be exact. However, these dimensions are considered to be acceptable rounded values for the accuracy considered. NOTE: For more details, see 9.1.3 of IEC 1169-1. *Where applicable, fill in millimeters or inches.
6 Standard Ratings and Characteristics
GB/T 11313-1996
The ratings and characteristics applicable to each connector type and variety shall be specified in the relevant specifications. They should generally include the following: a brief description of the connector structure, especially the inner diameter of the outer conductor, if applicable, the preferred cable model for the connector; a reflection coefficient of different grades of connectors as a function of frequency (if applicable), and the conditions under which it is effective should also be given; a working voltage at different altitudes (air pressure); a climate category;
——other applicable ratings or characteristics. 7 Xenon Climate Category Classification
Connector climate conditions are classified according to the provisions of IEC68-1, and are represented by three groups of digital series separated by slashes, respectively, indicating the corresponding low temperature test (no negative sign), the temperature of the high temperature test and the number of days of steady-state damp heat exposure. The climate severity to be specified in the relevant specifications should be selected from the following preferred values in priority (but not necessarily): Low temperature: 40℃, -55℃
High temperature: 85℃ (category 085), 125℃ and 155℃ Steady-state damp heat exposure days: 4d (category 04) 21d, 56d The following two groups are recommended as the priority climate categories for RF connectors: 40/085/21
55/155/21
8 Model naming
The purpose of model naming is to identify specific connectors within the scope of RF connection standards. It is not applicable to information outside this standard. In fact, this is usually necessary to identify the products of the manufacturer, because some products may not be the structures included in this standard although they adopt this standard.
Connectors that adopt the corresponding specifications should be named using the following symbols and sequence. a) Specification number;
b) Letters \GB/T\;
c) Additional identification marks indicated in the corresponding specifications. NOTE: When this type designation is used on the product marking or in the product manual, it is the responsibility of the manufacturer to ensure that the product complies with the requirements of the corresponding specification. No other party shall be held responsible for this.
9 Test methods
9.1 General
This clause covers the electrical and mechanical test methods, environmental conditions and test procedures used for type approval tests and their approval, but its content is also applicable to other tests. Requirements are not usually specified directly. However, when applicable, one or more preferred severities are given. The corresponding specification shall specify those tests, measurement methods and procedures selected from the tests included in this clause that are required for the specific product, as well as the appropriate severities and requirements.
For technical reasons, some tests are to be carried out on the same sample in a specified sequence. Separate samples may be required for different sequences. Since, for some tests, samples that have been subjected to these tests are not available, it is economical to group some tests into appropriate test groups.
A list of test groupings taking into account the above factors is given in 10.3.2.3. It is expected that this test list is applicable to all types of connectors in principle. For specific types and varieties, those tests or sequences that are not necessary can be deleted. According to the test list, all samples in a test sample shall be subjected to the first group of tests. Then, the sample shall be divided into the next sub-samples according to the required number. Unless otherwise specified, the sub-sample shall not be less than 4 pairs of connectors. 9.1.1 Standard conditions for tests
Unless otherwise specified, the following conditions shall be adopted: - The test shall be carried out under the standard atmospheric conditions for the test specified in IEC68-1. - Before measurement, the connector shall be preconditioned under the test standard atmospheric conditions for a period of time sufficient for the entire connector to reach thermal stability.
- The recovery conditions during the interval between the conditional test and the next measurement or test shall comply with the provisions of IEC68-1. See 10.3 for the test list and 9 for details of the conditional test.4. When only nominal values are given for the applied stress and/or duration of action, this specified value shall be considered to refer to the minimum test severity applied.
The test shall be carried out on the connector received from the supplier. Unless otherwise specified in the specification, cleaning or other treatment of the contacts shall not be allowed before the test.
If a section of cable needs to be attached to the connector, it shall be attached in accordance with the connector manufacturer's instructions (usually provided with the connector).
Connectors that are plugged into a socket shall be fully engaged, and threaded connectors shall be tightened to the nominal connection torque specified in the relevant specification. When the test requires installation, a clamp shall be used for free-end connectors and the normal installation method shall be used for fixed connectors to securely mount the connector on a rigid plate made of suitable material. The dimensions of the mounting plate shall be larger than the overall dimensions of the sample. For dynamic tests, such as collision, vibration and shock, the installation and configuration of the cable or wire shall be in accordance with IEC68-2-47. Unless otherwise specified in the relevant specification, the cable (or wire) shall be clamped on the test bench coaxially with the connector, at a distance of 90 mm ± 10 mm from each cable outlet. The free end of the cable shall be clamped on a rigid support to prevent its rotation. Unless otherwise specified in the relevant specification, the influence of gravity, the direction and energy level of the ordinary (earth) magnetic field shall be ignored when dynamic tests are carried out.
When installing the connector for environmental condition testing, care should be taken to ensure that the surface treatment of the mounting plate and the connector housing are compatible metals to avoid electrolytic corrosion caused by contact between incompatible metals. For sealed connectors, suitable test fixtures should be used so that they do not affect the panel seals. The leakage rate can be measured after the recovery period of the environmental condition test. Where applicable, the back of the panel where the above-mentioned connector is fixed should be protected. The free end of the cable should be protected to prevent moisture intrusion. For tests involving exposure to high temperatures (usually the upper category temperature in the climate sequence), such as rapid temperature changes and high temperature durability, suitable high temperature resistant cables should be used, but the specified upper temperature limit of the cable can be lower than the upper temperature limit of the connector. 9.1.2 Visual inspection
The visual inspection shall include:
a) Marking
The marking shall comply with the provisions of 11.1 and remain legible after any specified tests. b) Manufacturing
The manufacturing shall be carried out in a meticulous manner.
c) Damage after electrical, mechanical and climatic tests Unless otherwise specified, there shall be no visible damage that affects performance. d) Packaging marking
The marking shall comply with the provisions of 11.2.
9.7.3 Dimensions
The dimensions shall be inspected in accordance with the provisions of the relevant (or related) specifications. Any suitable method may be used for inspection unless the relevant specifications specify that standard gauges shall be used. 9.1.3.1 Overall dimensions
The overall dimensions shall comply with the provisions of the relevant specifications. When specified as a batch-by-batch inspection item, they may be inspected before final assembly. 261
9.1.3.2 Parts and Materials
GB/T 11313-1996
A set of parts provided in accordance with the requirements of the relevant specification shall be checked and conform to the drawings used in the application for identification approval or certification.
9.1.3.3 Mechanical Interchangeability
The dimensions of the mating surface shall conform to the mating surface drawings specified in the relevant specification. Interchangeability standard gauges may be used. When used, the sample shall be able to mate with the standard gauge. 9.2 Electrical Test and Measurement Procedures
9.2.1 Reflection Coefficient
9.2.1.1 General
The reflection coefficient of the RF connector shall be measured on the test sample mated with the standard test connector. The adapter shall be mated with the standard test connector at both ends.
The relevant specification for the specific connector shall also specify the corresponding standard test connector (Class 0 connector). The entire mated standard test connector pair, including the precision transmission line or cable, should present the most uniform characteristic impedance. The cable connector should be equipped with a suitable cable as specified in the instructions provided by the connector manufacturer. The cable used should preferably be of a type with strict precision tolerances. It is permitted to use a cable simulator instead of a cable. Time domain reflectometry (TDR) should be used to check the consistency of the measurement system, determine imperfections and detect the accuracy of the characteristic impedance of the coaxial transmission line segment used.
The reflection coefficient should be expressed as a function of frequency. The frequency domain method should usually be used for measurement, preferably with a swept frequency signal generator. When the frequency is below about 1 GHz, it is appropriate to measure first with the time domain method and then convert it into the frequency domain characteristics. It has the special advantage of separating the reflection caused by the connector under test from other reflections in the system. This is more difficult to achieve when measuring with the frequency domain method, especially at low frequencies. If a point frequency method other than the swept frequency method is used, a suitably small frequency increment should be used. Unless the signal generator (usually automatically controlled) allows very small frequency increments, the point frequency method is not suitable as a method of error resolution. Commonly used equipment for measuring the reflection coefficient as a function of frequency are: radio frequency bridges, directional couplers and slotted measuring lines. When no special measures are taken to distinguish the errors caused by different defects, measurement systems using such equipment are generally only suitable for measuring reflection coefficients greater than 0.05 (taking into account that the measurement inaccuracy should not be greater than 10% of the measured value). When testing connectors with a specified reflection coefficient limit value below 0.05, it is usually necessary to use a test system that can distinguish the error components and thus calculate the relevant reflection coefficient. Some computer-controlled automatic measurement systems have additional programs with error correction modes that can reduce the inaccuracy of reflection coefficient measurements without other resolution methods.
9.2.1.2 Contents to be specified in the corresponding specifications: a) The limit values of the appropriate level of reflection coefficient as a function of frequency; b) The accuracy of the measurement;
c) Details of standard test connectors;
d) The necessary characteristics of the applicable cable;
e) Any deviation from the standard test method. 9.2.1.3 Normal measurement method
9.2.1.4 Common measurement systems
Figure 1 shows a simple measurement system using a bridge or directional coupler or slotted measuring line, which is usually unable to identify the errors caused by different error sources. In Figure 1, the main locations where reflections may occur are marked as BC and D, and the corresponding reflection coefficients are marked as rh, r. and rd. The reflection coefficient caused by the connector under test is marked as rx. The test port error not only represents the reflection at point B, but also includes the residual error of the bridge or directional coupler or slotted measuring line. Since the phase of the individual reflected waves depends on the electrical length between the reflection points and, therefore, also on the frequency, their influence on the apparent total reflection coefficient is also random. Therefore, the RMS value is: 262
GB/T 11313-1996
Vr + (r?+r?+r)
For example, typical values may be: r = 0.018, r. = ra = 0.01, assuming rx = 0.05, then re = 1.1
This means that the inaccuracy is 10%. Of course, the values of each frequency point may also be affected by errors of varying degrees. Although Figure 1 indicates the use of a swept frequency signal generator, this does not exclude the use of the point frequency method in view of the predictions stated in 9.2.1.1. Sweep signal source
Bridge or directional coupler or slotted measuring line calibrated variable attenuator G
Detector
Logarithmic amplifier or network analyzer
Oscilloscope or XY recorder
①Bridge test port connector
②Standard test adapter
③Standard test connector
④Connector under test
③Cable or cable simulation device
Figure 1 Bridge, coupler or slotted measuring line method without error identification 9.2.1.5 Double Connector Method
The double connector method is a special measurement method that uses a pre-selected cable with accurate and uniform characteristic impedance to connect two test samples (connectors under test) that are as similar as possible as a test device. Although this method cannot identify errors, it can identify with a high probability whether there is a significant reflection in the connector. This method is shown in Figure 2. The principle is that for two identical test samples, the reflection coefficient as a function of frequency is also equal. In the interconnection section, whenever the distance between the two connectors is equal to an odd multiple of 1/4 wavelength, the reflections from the two connectors cancel each other, and when the distance is equal to an even multiple of 1/4 wavelength, the reflections are superimposed on each other, and the value is twice the value of a single reflection. Complete cancellation is a fairly reliable criterion for the exact equality of the reflections of the two connectors and the absence of parasitic reflections in the system. In actual measurements, the loss in the cable section prevents the echoes generated by the two connectors with equal reflection coefficients from completely canceling at the node. When the connector assembly reverses direction, the unequal reflections show their unequal minimum value. In general, low maximum values (low reflection coefficients) are acceptable when the minimum value does not change with reversal of the connector assembly orientation. However, if the corresponding maximum value of the reflection coefficient exceeds the specified value, or the minimum value changes significantly when the connector assembly is reversed, the connector and cable should be checked before retesting. The interconnecting cable of the connector should be a specified cable with verified performance or a suitable cable simulator. The cable length should not be longer than that required for the lowest frequency of the reflection coefficient to be measured. For a wide frequency range and when results are required at frequencies not enveloped by a series of antinodes, it may be appropriate to have several lengths.
To check the accuracy of the system, it is recommended to repeat the measurements by interchanging the connector assembly between standard test connectors. The two-connector method can be used in conjunction with the bridge, directional coupler or slotted measurement line method. The latter method is described in some detail below.
GB/T 11313—1996
Standard test adapter, connector under test see note
Standard test adapter
Precision terminal load
Note: The standard test connector can be used directly between the signal generator port and the precision terminal instead of the standard test adapter. Figure 2 Measurement setup for dual connector procedure
Figure 3 shows an XY graph of the voltage on the slotted measurement line as a function of frequency with the probe position (simply moving the probe through the appropriate distance after each frequency sweep) as a parameter, the voltage preferably uses a logarithmic scale with decibels (dB) as the division. The displayed curve can be plotted as an envelope. Therefore, the minimum width of the displayed curve can be determined. The reflection coefficient at a specific frequency can be derived from the voltage standing wave ratio (VSWR) corresponding to the maximum width of the envelope. The value of the reflection coefficient for a single connector corresponding to the maximum width is calculated by the following formula: 1 VSWR 1
2VSWR+1
Maximum width = -VSWR (dB) m
Related to the calculation of
Minimum value of
c = wave velocity in cable segment p
Linear particle scale
Figure 3 Voltage value as a function of frequency on the slotted measurement line with the probe position as a parameter 9.2.1.6 Measurement method with error identification
9.2.1.6.1 Use of a bridge
In order to be able to identify errors, two changes are made to the conventional measurement system shown in Figure 1. These two changes consist in installing transmission lines of sufficient length between the bridge test terminal 1B and the test assembly C and between the test assembly C and the matched load D. In addition, at the base of the bridge 264
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.