Network cable analog circuit and network testing device

Abstract

The utility model discloses a network cable simulation circuit and a network testing device, and the network cable simulation circuit comprises a first interface impedance equivalent unit, a second interface impedance equivalent unit, a transmission impedance equivalent unit, a third interface impedance equivalent unit, and a fourth interface impedance equivalent unit. And the transmission impedance equivalent unit is connected with the four third interface impedance equivalent units so as to simulate the equivalent impedance of the network cable per unit length. And the transmission impedance equivalent unit and the four third interface impedance equivalent units are used for equivalence of the overall impedance characteristics of the twisted pair in unit length during signal transmission. Therefore, the network cable simulation circuit can accurately simulate the overall impedance characteristics of the twisted pair with equivalent unit length during testing. When the network cable simulation circuit is used for replacing a twisted pair of unit length for network testing, a testing result can be close to a network testing value of an actual twisted pair with high precision, the testing is more convenient, and the efficiency of the network testing can be greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of network cable simulation, in particular to a network cable simulation circuit and a network testing device. Background Art

[0002] In today's rapidly developing economy, competition is fierce in all industries, especially in the industrial sector. The products made by industries compete not only on performance and quality, but also on price and cost. Therefore, cost control is particularly important for industrial industries.

[0003] During the production test of conventional switch products, an actual 100M network cable handle is used to insert the product for testing. For the production system, a multi-port switch, such as a 48-port switch, requires 24 100M network cables, which takes up too much space and is inconvenient for employees to operate. Usually, 8 or 12 100M network cables are used for segmented testing. In this way, a 48-port switch needs to be tested multiple times, affecting production efficiency.

[0004] Taking the production of 48-port switches as an example, conventional testing uses 24 100M network cables or 8 (12) network cables for segmented testing. The space occupied makes the test station completely covered by network cables. In addition, the interface positions of the switch product under test are all network cables, which limits the operation. Summary of the invention

[0005] The utility model aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one purpose of the utility model is to provide a network cable simulation circuit and a network testing device.

[0006] On the one hand, in order to achieve the above-mentioned purpose, the network cable simulation circuit according to the embodiment of the utility model includes:

[0007] A first interface impedance equivalent unit, one end of which is used to be connected to the first signal end to simulate the equivalent impedance of one end of the first network cable;

[0008] A second interface impedance equivalent unit, wherein one end of the second interface impedance equivalent unit is used to be connected to the second signal end to simulate the equivalent impedance of one end of the second network cable;

[0009] A transmission impedance equivalent unit, wherein two ends of one side of the transmission impedance equivalent unit are respectively connected to the other end of the first interface impedance equivalent unit and the other end of the second interface impedance equivalent unit to simulate the transmission equivalent impedance of the first network cable and the second network cable;

[0010] a third interface impedance equivalent unit, wherein one end of the third interface impedance equivalent unit is connected to one end of the other side of the transmission impedance equivalent unit, and the other end of the third interface impedance equivalent unit is used to be connected to a third signal end to simulate the equivalent impedance of the other end of the first network cable;

[0011] A fourth interface impedance equivalent unit, one end of the fourth interface impedance equivalent unit is connected to the other end of the other side of the transmission impedance equivalent unit, and the other end of the fourth interface impedance equivalent unit is used to connect to the fourth signal end to simulate the equivalent impedance of the other end of the second network cable.

[0012] Further, according to an embodiment of the present utility model, the transmission impedance equivalent unit includes:

[0013] A first equivalent inductor L99, one end of the first equivalent inductor L99 is connected to the other end of the first interface impedance equivalent unit, and the other end of the first equivalent inductor L99 is connected to the one end of the third interface impedance equivalent unit;

[0014] a second equivalent inductor L100, one end of the second equivalent inductor L100 is connected to the other end of the second interface impedance equivalent unit, and the other end of the second equivalent inductor L100 is connected to the one end of the fourth interface impedance equivalent unit;

[0015] The inductance value of the first equivalent inductor L99 is the same as the inductance value of the second equivalent inductor L100.

[0016] Further, according to an embodiment of the present utility model, the transmission impedance equivalent unit also includes:

[0017] A first equivalent capacitor C2, one end of the first equivalent capacitor C2 is connected to the one end of the first equivalent inductor L99;

[0018] a first equivalent resistor R152, wherein one end of the first equivalent resistor R152 is connected to the other end of the first equivalent capacitor C2, and the other end of the first equivalent resistor R152 is connected to the one end of the second equivalent inductor L100;

[0019] a second equivalent capacitor C10, wherein one end of the second equivalent capacitor C10 is connected to the other end of the first equivalent inductor L99;

[0020] a second equivalent resistor R151, wherein one end of the second equivalent resistor R151 is connected to the other end of the second equivalent capacitor C10, and the other end of the second equivalent resistor R151 is connected to the other end of the second equivalent inductor L100;

[0021] The capacitance value of the first equivalent capacitor C2 is the same as the capacitance value of the second equivalent capacitor C10; the resistance value of the first equivalent resistor R152 is the same as the resistance value of the second equivalent resistor R151.

[0022] Further, according to an embodiment of the present utility model, the transmission impedance equivalent unit also includes:

[0023] a first equivalent resistor R7, one end of the first equivalent resistor R7 is connected to one end of the first equivalent inductor L99, and the other end of the first equivalent resistor R7 is connected to the other end of the first equivalent inductor L99;

[0024] a second equivalent resistor R228, one end of the second equivalent resistor R228 is connected to one end of the second equivalent inductor L100, and the other end of the second equivalent resistor R228 is connected to the other end of the second equivalent inductor L100;

[0025] The resistance value of the first equivalent resistor R7 is the same as the resistance value of the second equivalent resistor R228.

[0026] Further, according to an embodiment of the present utility model, the first interface impedance equivalent unit includes:

[0027] a third equivalent resistor R11, one end of the third equivalent resistor R11 being connected to the first signal end, and the other end of the third equivalent resistor R11 being connected to the one end of the first equivalent inductor L99;

[0028] a fourth equivalent resistor R9, one end of the fourth equivalent resistor R9 being connected to the one end of the third equivalent resistor R11;

[0029] A third equivalent capacitor C25, one end of the third equivalent capacitor C25 is connected to the other end of the fourth equivalent resistor R9, and the other end of the third equivalent capacitor C25 is connected to the reference ground.

[0030] Further, according to an embodiment of the present utility model, the second interface impedance equivalent unit includes:

[0031] a fifth equivalent resistor R152, one end of the fifth equivalent resistor R152 being connected to the second signal end, and the other end of the fifth equivalent resistor R152 being connected to the one end of the second equivalent inductor L100;

[0032] a sixth equivalent resistor R216, one end of the sixth equivalent resistor R216 being connected to the one end of the fifth equivalent resistor R152;

[0033] a fourth equivalent capacitor C29, one end of the fourth equivalent capacitor C29 being connected to the other end of the sixth equivalent resistor R216, and the other end of the fourth equivalent capacitor C29 being connected to a reference ground;

[0034] Among them, the resistance value of the third equivalent resistor R11 is the same as the resistance value of the fifth equivalent resistor R152; the resistance value of the fourth equivalent resistor R9 is the same as the resistance value of the sixth equivalent resistor R216; the capacitance value of the third equivalent capacitor C25 is the same as the fourth equivalent capacitor C29.

[0035] Further, according to an embodiment of the present utility model, the third interface impedance equivalent unit includes:

[0036] a seventh equivalent resistor R149, one end of the seventh equivalent resistor R149 being connected to the third signal end, and the other end of the seventh equivalent resistor R149 being connected to the other end of the first equivalent inductor L99;

[0037] an eighth equivalent resistor R10, one end of the eighth equivalent resistor R10 being connected to the one end of the seventh equivalent resistor R149;

[0038] A fifth equivalent capacitor C26, one end of the fifth equivalent capacitor C26 is connected to the other end of the eighth equivalent resistor R10, and the other end of the fifth equivalent capacitor C26 is connected to the reference ground.

[0039] Further, according to an embodiment of the present utility model, the fourth interface impedance equivalent unit includes:

[0040] a ninth equivalent resistor R213, one end of the ninth equivalent resistor R213 being connected to the fourth signal end, and the other end of the ninth equivalent resistor R213 being connected to the other end of the second equivalent inductor L100;

[0041] a tenth equivalent resistor R225, one end of the tenth equivalent resistor R225 being connected to the one end of the ninth equivalent resistor R213;

[0042] a sixth equivalent capacitor C30, one end of the sixth equivalent capacitor C30 is connected to the other end of the tenth equivalent resistor R225, and the other end of the sixth equivalent capacitor C30 is connected to a reference ground;

[0043] Among them, the resistance value of the ninth equivalent resistor R213 is respectively the same as the resistance value of the seventh equivalent resistor R149 and the third equivalent resistor R11; the tenth equivalent resistor R225 is respectively the same as the resistance value of the eighth equivalent resistor R10 and the fourth equivalent resistor R9; the capacitance value of the sixth equivalent capacitor C30 is respectively the same as the fifth equivalent capacitor C26 and the fourth equivalent capacitor C29.

[0044] On the other hand, the embodiment of the utility model further provides a network testing device, including:

[0045] Four of the above-mentioned network cable simulation circuits; wherein the four network cable simulation circuits are respectively a first network cable simulation circuit, a second network cable simulation circuit, a third network cable simulation circuit and a fourth network cable simulation circuit;

[0046] A first signal connector J2, wherein the first signal connector J2 is respectively connected to a first interface impedance equivalent unit and a second interface impedance equivalent unit of the first network cable simulation circuit, and the first signal connector J2 is also respectively connected to a first interface impedance equivalent unit and a second interface impedance equivalent unit of the second network cable simulation circuit;

[0047] A second signal connector J1, wherein the second signal connector J1 is respectively connected to the first interface impedance equivalent unit and the second interface impedance equivalent unit of the third network cable simulation circuit, and the second signal connector J1 is also respectively connected to the first interface impedance equivalent unit and the second interface impedance equivalent unit of the fourth network cable simulation circuit;

[0048] A third signal connector J4, wherein the third signal connector J4 is respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the first network cable simulation circuit, and the third signal connector J4 is also respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the second network cable simulation circuit;

[0049] A fourth signal connector J3, wherein the fourth signal connector J3 is respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the third network cable simulation circuit, and the fourth signal connector J3 is also respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the fourth network cable simulation circuit;

[0050] The second signal connector J1 and the fourth signal connector J3 are also connected to each other via a connecting line.

[0051] Further, according to an embodiment of the present invention, the first signal connector J2 and the third signal connector J4 are RJ45 connectors respectively.

[0052] The network testing device provided by the embodiment of the utility model is connected with four third interface impedance equivalent units through a transmission impedance equivalent unit to simulate the equivalent impedance of a network cable per unit length. The overall impedance characteristics of a twisted pair per unit length during signal transmission are equivalent through the transmission impedance equivalent unit and the four third interface impedance equivalent units. In this way, the network cable simulation circuit can accurately simulate and equivalent the overall impedance characteristics of a twisted pair per unit length during testing. Using the network cable simulation circuit to replace a twisted pair per unit length for network testing can make the test results close to the network test value of the actual twisted pair with high accuracy, and the test is also more convenient, which can greatly improve the efficiency of network testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 This is a structural block diagram of the network cable simulation circuit provided by the utility model;

[0054] Figure 2 A schematic diagram of the structure of a first network cable simulation circuit and a second network cable simulation circuit provided on board A provided by the utility model;

[0055] Figure 3 A schematic diagram of the structure of the third network cable simulation circuit and the fourth network cable simulation circuit provided on the B board provided by the utility model;

[0056] Figure 4 The first signal connector and the second signal connector provided by the utility model are intended;

[0057] Figure 5 This is an intention of the third signal connector and the fourth signal connector provided by the utility model.

[0058] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0059] In order to make the technical personnel in the technical field better understand the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described in combination with the drawings in the embodiment of the present invention. Unless otherwise defined, all technical and scientific terms used in this article have the same meaning as those commonly understood by the technical personnel in the technical field of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0060] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0061] On the one hand, see Figure 1 The utility model provides a network cable simulation circuit, including: a first interface impedance equivalent unit, a second interface impedance equivalent unit, a transmission impedance equivalent unit, a third interface impedance equivalent unit and a fourth interface impedance equivalent unit, wherein one end of the first interface impedance equivalent unit is used to be connected to the first signal end to simulate the equivalent impedance of one end of the first network cable; one end of the second interface impedance equivalent unit is used to be connected to the second signal end to simulate the equivalent impedance of one end of the second network cable; two ends of one side of the transmission impedance equivalent unit are respectively connected to the other end of the first interface impedance equivalent unit and the other end of the second interface impedance equivalent unit to simulate the transmission equivalent impedance of the first network cable and the second network cable; one end of the third interface impedance equivalent unit is connected to one end of the other side of the transmission impedance equivalent unit, and the other end of the third interface impedance equivalent unit is used to be connected to the third signal end to simulate the equivalent impedance of the other end of the first network cable; one end of the fourth interface impedance equivalent unit is connected to the other end of the other side of the transmission impedance equivalent unit, and the other end of the fourth interface impedance equivalent unit is used to be connected to the fourth signal end to simulate the equivalent impedance of the other end of the second network cable.

[0062] Specifically, Figure 1As shown in , the network cable simulation circuit is an equivalent circuit of a unit length network cable to simulate the impedance of the unit length network cable. In one embodiment of the utility model, the simulated network cable can be a twisted pair. In this way, the network cable simulation circuit can replace the unit length twisted pair to test the network device. In this way, the test of the network device is more convenient. In which, the external signal ends (P1, SP1A) of the first interface impedance equivalent unit and the third interface impedance equivalent unit correspond to the two signal ends of a unit length twisted pair. And the external signal ends (P2, SP2A) of the second interface impedance equivalent unit and the fourth interface impedance equivalent unit correspond to the two signal ends of another unit length twisted pair. And the overall impedance characteristics of the unit length twisted pair during signal transmission are equivalent through five impedance equivalent units (the first interface impedance equivalent unit, the second interface impedance equivalent unit, the transmission impedance equivalent unit, the third interface impedance equivalent unit and the fourth interface impedance equivalent unit). In this way, the network cable simulation circuit can accurately simulate and equivalent the overall impedance characteristics of the unit length twisted pair during testing. In this way, using the network cable simulation circuit to replace the unit length of twisted pair for network testing can make the test results close to the network test value of the actual twisted pair with high accuracy, and the test is also more convenient, which can greatly improve the efficiency of network testing.

[0063] See also Figure 1 , the transmission impedance equivalent unit includes: a first equivalent inductor L99 and a second equivalent inductor L100, one end of the first equivalent inductor L99 is connected to the other end of the first interface impedance equivalent unit, and the other end of the first equivalent inductor L99 is connected to the one end of the third interface impedance equivalent unit; one end of the second equivalent inductor L100 is connected to the other end of the second interface impedance equivalent unit, and the other end of the second equivalent inductor L100 is connected to the one end of the fourth interface impedance equivalent unit; wherein the inductance value of the first equivalent inductor L99 is the same as the inductance value of the second equivalent inductor L100.

[0064] Specifically, the first equivalent inductor L99 and the second equivalent inductor L100 are used to simulate and equalize the self-inductance and mutual inductance of the actual unit length during network testing. Since the self-inductance and mutual inductance generated by the two signal lines in the twisted pair of equal length are the same. Therefore, the first equivalent inductor L99 and the second equivalent inductor L100 are usually in a strictly symmetrical relationship. Therefore, in the transmission impedance equivalent unit, the first equivalent inductor L99 and the second equivalent inductor L100 are respectively connected in series to the ideal transmission conductor to simulate and equalize the self-inductance and mutual inductance of the actual unit length during network testing.

[0065] See also Figure 1, the transmission impedance equivalent unit further includes: a first equivalent capacitor C2, a first equivalent resistor R152, a second equivalent capacitor C10 and a second equivalent resistor R151, one end of the first equivalent capacitor C2 is connected to the one end of the first equivalent inductor L99; one end of the first equivalent resistor R152 is connected to the other end of the first equivalent capacitor C2, and the other end of the first equivalent resistor R152 is connected to the one end of the second equivalent inductor L100; one end of the second equivalent capacitor C10 is connected to the other end of the first equivalent inductor L99;

[0066] One end of the second equivalent resistor R151 is connected to the other end of the second equivalent capacitor C10, and the other end of the second equivalent resistor R15 is connected to the other end of the second equivalent inductor L100; wherein, the capacitance value of the first equivalent capacitor C2 is the same as the capacitance value of the second equivalent capacitor C10; and the resistance value of the first equivalent resistor R152 is the same as the resistance value of the second equivalent resistor R151.

[0067] Specifically, the first equivalent capacitor C2 and the first equivalent resistor R152 form a group, and the second equivalent capacitor C10 and the second equivalent resistor R151 form another group. Two groups of capacitor and resistor equivalent circuits are respectively connected in series at both ends of the equivalent inductor (L99, L100) to simulate and equate the equivalent capacitance and insertion resistance of the actual unit length during network testing. Since the equivalent capacitance generated by the two signal lines in the twisted pair of equal length is the same. Therefore, the first equivalent capacitor C2, the first equivalent resistor R152 and the second equivalent capacitor C10, the second equivalent resistor R151 are usually in a strictly symmetrical relationship. Therefore, in the transmission impedance equivalent unit, the first equivalent capacitor C2 and the first equivalent resistor R152 are connected in parallel at one end of the equivalent inductor, and the second equivalent capacitor C10 and the second equivalent resistor R151 are connected in parallel at the other end of the equivalent inductor to simulate and equate the equivalent capacitance and resistance of the twisted pair of actual unit length during network testing.

[0068] See also Figure 1, the transmission impedance equivalent unit also includes: a first equivalent resistor R7 and a second equivalent resistor R228, one end of the first equivalent resistor R7 is connected to one end of the first equivalent inductor L99, and the other end of the first equivalent resistor R7 is connected to the other end of the first equivalent inductor L99; one end of the second equivalent resistor R228 is connected to one end of the second equivalent inductor L100, and the other end of the second equivalent resistor R228 is connected to the other end of the second equivalent inductor L100; wherein the resistance value of the first equivalent resistor R7 is the same as the resistance value of the second equivalent resistor R228. Specifically, the first equivalent resistor R7 is connected in parallel with the first equivalent inductor L99, and the second equivalent resistor R228 is connected in parallel with the second equivalent inductor L100. Further simulate and equate the self-inductance, mutual inductance and static resistance value of the actual unit length during network testing. Since the transmission characteristics of twisted pairs of equal length are the same, the first equivalent resistor R7 and the second equivalent resistor R228 are equivalent using the same resistance value.

[0069] See also Figure 1 The first interface impedance equivalent unit includes: a third equivalent resistor R11, a fourth equivalent resistor R9 and a third equivalent capacitor C25, one end of the third equivalent resistor R11 is used to connect to the first signal end, and the other end of the third equivalent resistor R11 is connected to the one end of the first equivalent inductor L99; one end of the fourth equivalent resistor R9 is connected to the one end of the third equivalent resistor R11; one end of the third equivalent capacitor C25 is connected to the other end of the fourth equivalent resistor R9, and the other end of the third equivalent capacitor C25 is connected to the reference ground.

[0070] The second interface impedance equivalent unit includes: a fifth equivalent resistor R152, a sixth equivalent resistor R216 and a fourth equivalent capacitor C29, one end of the fifth equivalent resistor R152 is used to connect to the second signal end, and the other end of the fifth equivalent resistor R152 is connected to the one end of the second equivalent inductor L100; one end of the sixth equivalent resistor R216 is connected to the one end of the fifth equivalent resistor R152; one end of the fourth equivalent capacitor C29 is connected to the other end of the sixth equivalent resistor R216, and the other end of the fourth equivalent capacitor C29 is connected to the reference ground; wherein the resistance value of the third equivalent resistor R11 is the same as the resistance value of the fifth equivalent resistor R152; the resistance value of the fourth equivalent resistor R9 is the same as the resistance value of the sixth equivalent resistor R216;

[0071] The capacitance value of the third equivalent capacitor C25 is the same as that of the fourth equivalent capacitor C29. The third interface impedance equivalent unit includes: a seventh equivalent resistor R149, an eighth equivalent resistor R10 and a fifth equivalent capacitor C26, one end of the seventh equivalent resistor R149 is used to connect to the third signal terminal, and the other end of the seventh equivalent resistor R149 is connected to the other end of the first equivalent inductor L99; one end of the eighth equivalent resistor R10 is connected to the one end of the seventh equivalent resistor R149; one end of the fifth equivalent capacitor C26 is connected to the other end of the eighth equivalent resistor R10, and the other end of the fifth equivalent capacitor C26 is connected to the reference ground.

[0072] The fourth interface impedance equivalent unit includes: a ninth equivalent resistor R213, a tenth equivalent resistor R225 and a sixth equivalent capacitor C30, one end of the ninth equivalent resistor R213 is used to be connected to the fourth signal end, and the other end of the ninth equivalent resistor R213 is connected to the other end of the second equivalent inductor L100;

[0073] One end of the tenth equivalent resistor R225 is connected to the one end of the ninth equivalent resistor R213; one end of the sixth equivalent capacitor C30 is connected to the other end of the tenth equivalent resistor R225, and the other end of the sixth equivalent capacitor C30 is connected to the reference ground; wherein, the resistance value of the ninth equivalent resistor R213 is respectively the same as the resistance value of the seventh equivalent resistor R149 and the third equivalent resistor R11; the tenth equivalent resistor R225 is respectively the same as the resistance value of the eighth equivalent resistor R10 and the fourth equivalent resistor R9; the capacitance value of the sixth equivalent capacitor C30 is respectively the same as the fifth equivalent capacitor C26 and the fourth equivalent capacitor C29.

[0074] like Figure 1As shown in , the impedance characteristics at the interface of the twisted pair per unit length are simulated by using the first interface impedance equivalent unit, the third interface impedance equivalent unit, the second interface impedance equivalent unit and the fourth interface impedance equivalent unit. Since the equivalent impedance at the input and output interfaces of the twisted pair of equal length is the same. Therefore, the four interface equivalent units are in a strict mirror relationship, and the mirror image is a resistor or capacitor with the same resistance value. The four interface equivalent units use the same circuit structure. Among them, taking the first interface impedance equivalent unit as an example, by connecting the series resistor R11 between the equivalent inductance and the first signal terminal (P1), the static resistance of the first wire interface end of the twisted pair can be equivalent. After the fourth equivalent resistor R9 and the third equivalent capacitor C25 are connected in series, they are connected in parallel at the first signal terminal (P1) as the equivalent capacitance and resistance at a connecting line port of the twisted pair per unit length during the network test. The circuit structure and equivalent value of the remaining third interface impedance equivalent unit, the second interface impedance equivalent unit and the fourth interface impedance equivalent unit are the same as those of the first interface impedance equivalent unit. Therefore, the equivalent simulation effect is the same and will not be repeated here.

[0075] On the other hand, see Figures 2 to 5 The utility model embodiment also provides a network testing device, comprising: four groups of the above-mentioned network cable simulation circuits, a first signal connector J2, a second signal connector J1, a third signal connector J4 and a fourth signal connector J3; wherein the four network cable simulation circuits are respectively a first network cable simulation circuit, a second network cable simulation circuit, a third network cable simulation circuit and a fourth network cable simulation circuit; the first signal connector J2 is respectively connected to the first interface impedance equivalent unit and the second interface impedance equivalent unit of the first network cable simulation circuit, and the first signal connector J2 is also respectively connected to the first interface impedance equivalent unit and the second interface impedance equivalent unit of the second network cable simulation circuit; the second signal connector J1 is respectively connected to the first interface impedance equivalent unit and the second interface impedance equivalent unit of the third network cable simulation circuit, and the first signal connector J2 is also respectively connected to the first interface impedance equivalent unit and the second interface impedance equivalent unit of the second network cable simulation circuit. The second signal connector J1 is also respectively connected to the first interface impedance equivalent unit and the second interface impedance equivalent unit of the fourth network cable simulation circuit; the third signal connector J4 is respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the first network cable simulation circuit, and the third signal connector J4 is also respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the second network cable simulation circuit; the fourth signal connector J3 is respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the third network cable simulation circuit, and the fourth signal connector J3 is also respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the fourth network cable simulation circuit; wherein, the second signal connector J1 and the fourth signal connector J3 are also interconnected through a connecting line.

[0076] like Figures 3 to 5As shown in, the utility model embodiment adopts four of the network cable simulation circuits and four connectors to form a network testing device. In order to realize the simulation of a 100-meter twisted pair cable, the network testing device can replace the 100-meter twisted pair cable to perform data reception and transmission tests on network equipment. Among them, the first network cable simulation circuit, the second network cable simulation circuit, the first signal connector J2 and the second signal connector J1 can be arranged on the first circuit board A. The second network cable simulation circuit, the third network cable simulation circuit, the third signal connector J4, and the fourth signal connector J3 can be arranged on the second circuit board B. The first circuit board A and the second circuit board B can be connected by a connecting line, that is, after the second signal connector J1 and the fourth signal connector J3 are connected by the connecting line, the signals of the first circuit board A and the second circuit board B can be connected (such as Figure 5 In this way, two parallel unit network cable simulation circuits can be connected to another two parallel unit network cable simulation circuits, thereby simulating a twisted pair of 8 wires. The unit length can be 100 meters.

[0077] Further, in one embodiment of the utility model, the first signal connector J2 and the third signal connector J4 are respectively RJ45 connectors, and the two RJ45 connectors can be connected to network devices through network cables to realize data transmission and reception, so that a 100-meter network cable can be simulated to perform data transmission and reception test on the network device. The RJ45 connector is convenient for connection.

[0078] The above are only embodiments of the utility model, but they do not limit the patent scope of the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above specific implementations, or replace some of the technical features therein with equivalents. Any equivalent structure made by using the contents of the utility model specification and drawings, directly or indirectly used in other related technical fields, is also within the scope of protection of the utility model patent.

[0079] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0080] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations on the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention, all of which are within the scope of protection of the present invention.

Claims

1. A network cable simulation circuit, characterized in that: include: A first interface impedance equivalent unit, one end of which is used to be connected to the first signal end to simulate an equivalent impedance of one end of the first network cable; A second interface impedance equivalent unit, wherein one end of the second interface impedance equivalent unit is used to be connected to the second signal end to simulate the equivalent impedance of one end of the second network cable; A transmission impedance equivalent unit, wherein two ends of one side of the transmission impedance equivalent unit are respectively connected to the other end of the first interface impedance equivalent unit and the other end of the second interface impedance equivalent unit to simulate the transmission equivalent impedance of the first network cable and the second network cable; a third interface impedance equivalent unit, wherein one end of the third interface impedance equivalent unit is connected to one end of the other side of the transmission impedance equivalent unit, and the other end of the third interface impedance equivalent unit is used to be connected to a third signal end to simulate the equivalent impedance of the other end of the first network cable; A fourth interface impedance equivalent unit, one end of the fourth interface impedance equivalent unit is connected to the other end of the other side of the transmission impedance equivalent unit, and the other end of the fourth interface impedance equivalent unit is used to connect to the fourth signal end to simulate the equivalent impedance of the other end of the second network cable.

2. The network cable simulation circuit according to claim 1, characterized in that: The transmission impedance equivalent unit comprises: a first equivalent inductor (L99), one end of the first equivalent inductor (L99) being connected to the other end of the first interface impedance equivalent unit, and the other end of the first equivalent inductor (L99) being connected to the one end of the third interface impedance equivalent unit; a second equivalent inductor (L100), one end of the second equivalent inductor (L100) being connected to the other end of the second interface impedance equivalent unit, and the other end of the second equivalent inductor (L100) being connected to the one end of the fourth interface impedance equivalent unit; The inductance value of the first equivalent inductor (L99) is the same as the inductance value of the second equivalent inductor (L100).

3. The network cable simulation circuit according to claim 2, characterized in that: The transmission impedance equivalent unit also includes: a first equivalent capacitor (C2), one end of the first equivalent capacitor (C2) being connected to the one end of the first equivalent inductor (L99); a first equivalent resistor (R152), one end of the first equivalent resistor (R152) being connected to the other end of the first equivalent capacitor (C2), and the other end of the first equivalent resistor (R152) being connected to the one end of the second equivalent inductor (L100); a second equivalent capacitor (C10), one end of the second equivalent capacitor (C10) being connected to the other end of the first equivalent inductor (L99); a second equivalent resistor (R151), one end of the second equivalent resistor (R151) being connected to the other end of the second equivalent capacitor (C10), and the other end of the second equivalent resistor (R151) being connected to the other end of the second equivalent inductor (L100); Among them, the capacitance value of the first equivalent capacitor (C2) is the same as the capacitance value of the second equivalent capacitor (C10); the resistance value of the first equivalent resistor (R152) is the same as the resistance value of the second equivalent resistor (R151).

4. The network cable simulation circuit according to claim 3, characterized in that: The transmission impedance equivalent unit also includes: a first equivalent resistor (R7), one end of the first equivalent resistor (R7) being connected to one end of the first equivalent inductor (L99), and the other end of the first equivalent resistor (R7) being connected to the other end of the first equivalent inductor (L99); a second equivalent resistor (R228), one end of the second equivalent resistor (R228) being connected to one end of the second equivalent inductor (L100), and the other end of the second equivalent resistor (R228) being connected to the other end of the second equivalent inductor (L100); The resistance value of the first equivalent resistor (R7) is the same as the resistance value of the second equivalent resistor (R228).

5. The network cable simulation circuit according to any one of claims 2 to 4, characterized in that: The first interface impedance equivalent unit comprises: a third equivalent resistor (R11), one end of the third equivalent resistor (R11) being connected to the first signal end, and the other end of the third equivalent resistor (R11) being connected to the one end of the first equivalent inductor (L99); a fourth equivalent resistor (R9), one end of the fourth equivalent resistor (R9) being connected to the one end of the third equivalent resistor (R11); A third equivalent capacitor (C25), one end of the third equivalent capacitor (C25) is connected to the other end of the fourth equivalent resistor (R9), and the other end of the third equivalent capacitor (C25) is connected to a reference ground.

6. The network cable simulation circuit according to claim 5, characterized in that: The second interface impedance equivalent unit includes: a fifth equivalent resistor (R152), one end of the fifth equivalent resistor (R152) being connected to the second signal end, and the other end of the fifth equivalent resistor (R152) being connected to the one end of the second equivalent inductor (L100); a sixth equivalent resistor (R216), one end of the sixth equivalent resistor (R216) being connected to the one end of the fifth equivalent resistor (R152); a fourth equivalent capacitor (C29), one end of the fourth equivalent capacitor (C29) being connected to the other end of the sixth equivalent resistor (R216), and the other end of the fourth equivalent capacitor (C29) being connected to a reference ground; Among them, the resistance value of the third equivalent resistor (R11) is the same as the resistance value of the fifth equivalent resistor (R152); the resistance value of the fourth equivalent resistor (R9) is the same as the resistance value of the sixth equivalent resistor (R216); and the capacitance value of the third equivalent capacitor (C25) is the same as the capacitance value of the fourth equivalent capacitor (C29).

7. The network cable simulation circuit according to claim 6, characterized in that: The third interface impedance equivalent unit comprises: a seventh equivalent resistor (R149), one end of the seventh equivalent resistor (R149) being connected to the third signal end, and the other end of the seventh equivalent resistor (R149) being connected to the other end of the first equivalent inductor (L99); an eighth equivalent resistor (R10), one end of the eighth equivalent resistor (R10) being connected to the one end of the seventh equivalent resistor (R149); A fifth equivalent capacitor (C26), one end of the fifth equivalent capacitor (C26) is connected to the other end of the eighth equivalent resistor (R10), and the other end of the fifth equivalent capacitor (C26) is connected to a reference ground.

8. The network cable simulation circuit according to claim 7, characterized in that: The fourth interface impedance equivalent unit comprises: a ninth equivalent resistor (R213), one end of the ninth equivalent resistor (R213) being connected to the fourth signal end, and the other end of the ninth equivalent resistor (R213) being connected to the other end of the second equivalent inductor (L100); a tenth equivalent resistor (R225), one end of the tenth equivalent resistor (R225) being connected to the one end of the ninth equivalent resistor (R213); a sixth equivalent capacitor (C30), one end of the sixth equivalent capacitor (C30) being connected to the other end of the tenth equivalent resistor (R225), and the other end of the sixth equivalent capacitor (C30) being connected to a reference ground; Among them, the resistance value of the ninth equivalent resistor (R213) is respectively the same as the resistance value of the seventh equivalent resistor (R149) and the third equivalent resistor (R11); the tenth equivalent resistor (R225) is respectively the same as the resistance value of the eighth equivalent resistor (R10) and the fourth equivalent resistor (R9); the capacitance value of the sixth equivalent capacitor (C30) is respectively the same as the fifth equivalent capacitor (C26) and the fourth equivalent capacitor (C29).

9. A network testing device, characterized in that: include: Four network cable simulation circuits as described in any one of claims 1 to 8; wherein the four network cable simulation circuits are respectively a first network cable simulation circuit, a second network cable simulation circuit, a third network cable simulation circuit and a fourth network cable simulation circuit; A first signal connector (J2), the first signal connector (J2) being connected to a first interface impedance equivalent unit and a second interface impedance equivalent unit of the first network cable simulation circuit respectively, and the first signal connector (J2) being also connected to a first interface impedance equivalent unit and a second interface impedance equivalent unit of the second network cable simulation circuit respectively; A second signal connector (J1), wherein the second signal connector (J1) is respectively connected to the first interface impedance equivalent unit and the second interface impedance equivalent unit of the third network cable simulation circuit, and the second signal connector (J1) is also respectively connected to the first interface impedance equivalent unit and the second interface impedance equivalent unit of the fourth network cable simulation circuit; A third signal connector (J4), the third signal connector (J4) being respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the first network cable simulation circuit, and the third signal connector (J4) being also respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the second network cable simulation circuit; A fourth signal connector (J3), the fourth signal connector (J3) being respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the third network cable simulation circuit, and the fourth signal connector (J3) being also respectively connected to the third interface impedance equivalent unit and the fourth interface impedance equivalent unit of the fourth network cable simulation circuit; The second signal connector (J1) and the fourth signal connector (J3) are also connected to each other via a connecting line.

10. The network testing device according to claim 9, characterized in that: The first signal connector (J2) and the third signal connector (J4) are respectively RJ45 connectors.

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