Communication devices and communication systems

Abstract

This utility model discloses a communication device and a communication system, relating to the field of communication technology. The communication device includes: a first conversion unit, adapted to connect to a hub box of a logging system, configured to receive UART signals transmitted from the hub box and convert them into current signals; and a second conversion unit, connected to the first conversion unit via a twisted-pair shielded cable and adapted to connect to a host computer, configured to receive current signals transmitted from the twisted-pair shielded cable and convert them into USB signals, and transmit the USB signals to the host computer. Because current signals are very insensitive to voltage drops and electromagnetic noise on the line, even if induced noise occurs on the line due to long distance, the magnitude of the current will not change, thus ensuring a stable and reliable signal. Therefore, long-distance communication between the host computer and the hub box can be achieved with strong anti-interference capabilities.

Description

Technical Field

[0001] This utility model relates to the field of communication technology, and in particular to a communication device and a communication system. Background Technology

[0002] When the instrument is operating downhole, signals are transmitted to the surface via drilling mud. Mud sensors (such as riser pressure sensors) connected to a junction box collect these mud signals. The junction box processes the collected mud signals and uploads the processed data to a PC. However, because the mud sensors and junction box are located near the derrick, while the operators are in the instrument room, the distance between the two locations is considerable. Furthermore, various interferences exist at the well site, which can affect data communication. Utility Model Content

[0003] The purpose of this invention is to provide a communication device and system that enables long-distance communication and has strong anti-interference capabilities.

[0004] In a first aspect, this utility model proposes a communication device, the device comprising: a first conversion unit adapted to connect to a hub box of a logging system, configured to receive UART signals transmitted by the hub box and convert them into current signals; and a second conversion unit connected to the first conversion unit via a twisted-pair shielded cable and adapted to connect to a host computer, configured to receive current signals transmitted by the twisted-pair shielded cable and convert them into USB signals, and to transmit the USB signals to the host computer.

[0005] In some examples, the first conversion unit includes: a first microcontroller adapted to connect to the hub and configured to receive UART signals transmitted by the hub and convert them into voltage signals; a digital-to-analog converter connected to the first microcontroller and configured to convert the voltage signals from digital form to analog form; and a voltage-to-current conversion circuit connected to the first microcontroller and configured to convert the analog voltage signals into current signals.

[0006] In some examples, the voltage-to-current conversion circuit includes a first resistor, a first operational amplifier, and a switching transistor. The non-inverting input of the first operational amplifier is connected to the digital-to-analog converter, the inverting input of the first operational amplifier is connected to one end of the first resistor and the first end of the switching transistor, the output of the first operational amplifier is connected to the control terminal of the switching transistor, the other end of the first resistor is grounded, and the second end of the switching transistor is connected to the twisted-pair shielded cable.

[0007] In some examples, the voltage-to-current conversion circuit further includes a second resistor and a third resistor, the second resistor being connected between the non-inverting input of the first operational amplifier and the output of the first microcontroller, and the third resistor being connected between the output of the operational amplifier and the control terminal of the switching transistor.

[0008] In some examples, the switching transistor is a P-type transistor.

[0009] In some examples, the second conversion unit includes: a current-to-voltage conversion circuit connected to the twisted-pair shielded cable and configured to convert a current signal transmitted through the twisted-pair shielded cable into a voltage signal; an analog-to-digital converter connected to the current-to-voltage conversion circuit and configured to convert the voltage signal from analog to digital form; a second microcontroller connected to the analog-to-digital converter and configured to convert the digital voltage signal into a UART signal; and a USB conversion chip adapted to connect to the host computer and configured to convert the UART signal into a USB signal and transmit it to the host computer.

[0010] In some examples, the current-to-voltage conversion circuit includes a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a second operational amplifier. One end of the fourth resistor is connected to the twisted-pair shielded cable and one end of the fifth resistor. The other end of the fourth resistor is connected to one end of the sixth resistor. The other end of the fifth resistor is connected to the inverting input of the second operational amplifier and one end of the seventh resistor. The other end of the sixth resistor is connected to the non-inverting input of the second operational amplifier and one end of the eighth resistor. The other end of the eighth resistor is grounded. The other end of the seventh resistor is connected to the output of the second operational amplifier and the input of the analog-to-digital converter.

[0011] In some examples, the digital-to-analog converter is integrated in the first microcontroller, and the analog-to-digital converter is integrated in the second microcontroller.

[0012] In some examples, the shielding layer of the twisted-pair shielded cable is grounded at the end connected to the second conversion unit and suspended at the end connected to the first conversion unit, and the length of the twisted-pair shielded cable is greater than 40 meters.

[0013] Secondly, this utility model proposes a communication system, including: a host computer, a hub box, and the communication device described in the first aspect.

[0014] The communication device and system of this utility model, by sequentially connecting a first conversion unit, a twisted-pair shielded cable, and a second conversion unit between the junction box of the logging system and the host computer in the instrument room, realizes the conversion of UART signals into current signals, the transmission of current signals, and the conversion of current signals into USB signals. Since current signals are very insensitive to voltage drops and electromagnetic noise on the line, even if induced noise occurs on the line due to long distance, it will not change the current magnitude, thus ensuring signal stability and reliability. Therefore, long-distance communication between the host computer and the junction box can be achieved with strong anti-interference capabilities. Attached Figure Description

[0015] Figure 1 This is a structural block diagram of the communication device according to an embodiment of the present utility model; Figure 2 This is a schematic diagram of the structure of the first conversion unit of an example of this utility model; Figure 3 This is a topology diagram of a voltage-to-current conversion circuit according to an example of this utility model; Figure 4 This is a topology diagram of a voltage-to-current conversion circuit, another example of this utility model; Figure 5 This is a schematic diagram of the second conversion unit of an example of this utility model; Figure 6 This is a topology diagram of an example current-to-voltage conversion circuit of this utility model; Figure 7 This is a structural block diagram of the communication system according to an embodiment of the present utility model. Detailed Implementation

[0016] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0017] The communication device and communication system of the present invention are described below with reference to the accompanying drawings.

[0018] Figure 1 This is a structural block diagram of the communication device according to an embodiment of the present utility model.

[0019] like Figure 1As shown, the communication device 10 includes: a first conversion unit 11, a twisted-pair shielded cable 1, and a second conversion unit 12. The first conversion unit 11 is adapted to connect to the junction box 20 of the logging system and is configured to receive UART signals transmitted from the junction box 20 and convert them into current signals. The second conversion unit 12 is connected to the first conversion unit 11 via the twisted-pair shielded cable 1 and is adapted to connect to a host computer 30. It is configured to receive the current signals transmitted from the twisted-pair shielded cable 1, convert them into USB signals, and transmit the USB signals to the host computer 30.

[0020] In this embodiment, the hub box 20 near the derrick processes the data as UART signal data. After passing through the first conversion unit 11 located near the hub box 20, it can be converted into a current signal. This current signal is transmitted through the twisted-pair shielded cable 1 to the second conversion unit 12 located in the instrument room, where it can be converted into a USB signal and transmitted to the host computer (30) in the instrument room for processing. The twisted-pair shielded cable 1 is longer than 40 meters, which is greater than the distance between the hub box 20 and the host computer 30, such as 100 meters. Since the current signal is very insensitive to voltage drop and electromagnetic noise on the line, even if induced noise is generated on the line due to the long distance, it will not change the magnitude of the current, so the signal is stable and reliable. Furthermore, within the specified power supply voltage and load range, the current value will not attenuate from the first conversion unit 11 to the second conversion unit 12, achieving lossless transmission and ensuring the consistency of the signals at both ends. Thus, long-distance signal transmission between the hub box 20 and the host computer 30 can be realized through the communication device 10, with stable communication and strong anti-interference capability.

[0021] For example, the shielding layer of the twisted pair shielded cable 1 is grounded at one end connected to the second conversion unit 12 and left suspended at the other end connected to the first conversion unit 11.

[0022] This avoids the formation of "ground loops," effectively suppressing low-frequency common-mode interference and improving communication reliability.

[0023] In some embodiments, the communication device 10 may further include a fault detection unit, which may be installed on the ground and connected to the twisted-pair shielded cable 1, for detecting whether there is a circuit fault.

[0024] For example, the current signal range can be 4mA-20mA. 4mA corresponds to the "zero" pressure pulse signal processed by junction box 20, and 20mA corresponds to the maximum pressure pulse signal processed by junction box 20. If the fault detection unit detects a current signal less than 4mA, such as 0mA, it indicates an open circuit (broken wire); if the fault detection unit detects a current signal exceeding 20mA, it indicates a line fault. After detecting a fault, the fault detection unit can issue an alarm signal, such as an audible or electrical alarm, so that staff can be notified and repairs can be carried out promptly.

[0025] In some examples of this utility model, such as Figure 2 As shown, the first conversion unit 11 includes: a first microcontroller 111, a digital-to-analog converter 112, and a voltage-to-current conversion circuit 113.

[0026] The first microcontroller 111 is adapted to be connected to the hub 20 and is configured to receive the UART signal transmitted by the hub 20 and convert it into a voltage signal; the digital-to-analog converter 112 is connected to the first microcontroller 111 and is configured to convert the voltage signal from digital form to analog form; the voltage-to-current conversion circuit 113 is connected to the first microcontroller 111 and is configured to convert the analog voltage signal into a current signal.

[0027] Specifically, the junction box 20 processes the raw pressure signal (such as filtering and decoding) to obtain a UART signal representing downhole data. This UART signal is first converted into a digital voltage signal by the first microcontroller 111, then converted into an analog voltage signal by the digital-to-analog converter 112, and finally output as a current signal by the voltage-to-current conversion circuit 113. For example, zero pressure corresponds to a 1V voltage signal and a 4mA current signal, while full-scale pressure corresponds to a 5V voltage signal and a 20mA current signal.

[0028] For example, the digital-to-analog converter 112 is integrated into the first microcontroller 111. Compared to an external digital-to-analog converter 112, integrating the digital-to-analog converter 112 into the first microcontroller 111 simplifies circuit design, reduces costs, and improves communication reliability.

[0029] As one implementation method, such as Figure 3 As shown, the voltage-to-current conversion circuit 113 includes a first resistor R1, a first operational amplifier OP1, and a switching transistor T. The non-inverting input of the first operational amplifier OP1 is connected to the digital-to-analog converter 112. The inverting input of the first operational amplifier OP1 is connected to one end of the first resistor R1 and the first end of the switching transistor T. The output of the first operational amplifier OP1 is connected to the control terminal of the switching transistor T. The other end of the first resistor R1 is grounded. The second end of the switching transistor T is connected to the twisted-pair shielded cable 1.

[0030] See Figure 3The first operational amplifier OP1 serves as a comparator and amplifier; the switching transistor T acts as a power output device, providing the current required by the circuit; the first resistor R1 acts as a sampling resistor, used to feed the current signal back to the operational amplifier. The voltage signal Vin output by the digital-to-analog converter 112 is transmitted to the non-inverting input of the first operational amplifier OP1, and the output current Iout flows through the first resistor R1, generating a feedback voltage Vf (with a value of Iout × R1) across the first resistor R1. The feedback voltage Vf is connected to the inverting input of the first operational amplifier OP1.

[0031] The core objective of the first operational amplifier OP1 is to equalize the voltages at its two input terminals. If the output current Iout decreases, causing Vf < Vin, the first operational amplifier OP1 will increase its output, driving the switch T to allow more current to flow, thus raising Vf until it equals Vin again. If the output current Iout increases, causing Vf > Vin, the first operational amplifier OP1 will decrease its output, driving the switch T to reduce the current, thus lowering Vf until it equals Vin again. Ultimately, the voltage-to-current conversion circuit 113 will stabilize in a state that satisfies Vin = Iout × R1. Therefore, the output current can be derived as: Iout = Vin / R1.

[0032] Since the first resistor R1 is a precision resistor with a fixed value, the output current Iout is linearly determined by the input voltage Vin. Even though the twisted-pair shielded cable 1 has resistance, which causes a voltage drop (line loss), the current is the same throughout the entire loop. Therefore, the current measured by the second conversion unit 12 is exactly the same as the current value output by the first conversion unit 11, thus avoiding signal attenuation problems.

[0033] For example, see Figure 3 The switching transistor T is a P-type transistor.

[0034] Furthermore, such as Figure 4 As shown, the voltage-to-current conversion circuit 113 may also include a second resistor R2 and a third resistor R3. The second resistor R2 is connected between the non-inverting input terminal of the first operational amplifier OP1 and the output terminal of the first microcontroller 111, and the third resistor R3 is connected between the output terminal of the first operational amplifier OP1 and the control terminal of the switching transistor T.

[0035] The second resistor R2 and the third resistor R3 can be selected according to needs, such as the second resistor R2 having a resistance of 10kΩ and the third resistor R3 having a resistance of 1kΩ. The second resistor R2 and the first resistor R1 together determine the voltage-to-current conversion coefficient, and the third resistor R3 can be used to limit the output current of the first operational amplifier OP1, thereby improving the stability of the circuit.

[0036] In some examples of this utility model, such as Figure 5 As shown, the second conversion unit 12 includes: a current-to-voltage conversion circuit 121, an analog-to-digital converter 122, a second microcontroller 123, and a USB conversion chip U.

[0037] The current-to-voltage conversion circuit 121 is connected to the twisted-pair shielded cable 1 and is configured to convert the current signal transmitted by the twisted-pair shielded cable 1 into a voltage signal; the analog-to-digital converter 122 is connected to the current-to-voltage conversion circuit 121 and is configured to convert the voltage signal from analog to digital form; the second microcontroller 123 is connected to the analog-to-digital converter 122 and is configured to convert the digital voltage signal into a UART signal; the USB conversion chip U is adapted to connect to the host computer 30 and is configured to convert the UART signal into a USB signal and transmit it to the host computer 30.

[0038] Specifically, the current-to-voltage conversion circuit 121 may include a sampling resistor (which can be a high-precision, low-temperature-drift resistor). According to Ohm's law, the current signal (e.g., 4mA-20mA) transmitted from the twisted-pair shielded cable 1 flows through a sampling resistor of known resistance (e.g., 250Ω), generating a voltage drop across the sampling resistor: e.g., 4mA × 250Ω = 1V, 20mA × 250Ω = 5V. Thus, the 4-20mA current signal can be linearly converted into a 1-5V voltage signal. Of course, the sampling resistor may also use a resistor of other resistance values, such as 500Ω.

[0039] The voltage signal converted by the current-to-voltage conversion circuit 121 is in analog form. To be understood by a host computer, it must be digitized. An analog-to-digital converter 122 can be used to sample and quantize the voltage signal at a certain sampling rate. For example, a 12-bit ADC divides the 0-5V voltage range into 4096 parts. This converts a continuous voltage value into a discrete digital value (e.g., 2.5V might be converted to a digital value of 2048).

[0040] After receiving the digital signal, the second microcontroller 123 (or a dedicated interface chip such as FTDI or CP2102) packages the digital signal, adding information such as channel number and timestamp, and converts it into a UART signal according to a specific communication protocol (such as Modbus or a custom ASCII protocol). The MCU then transmits the UART signal via the UART (serial port). Afterwards, a USB converter chip (such as CH340N or FT232RL) captures the UART signal, converts it into a USB signal, and connects it to the host computer 30 via a USB cable.

[0041] For example, the analog-to-digital converter 122 is integrated into the second microcontroller 123. Compared to an external analog-to-digital converter 122, integrating the analog-to-digital converter 122 into the second microcontroller 123 simplifies circuit design, reduces costs, and improves communication reliability.

[0042] As one implementation method, such as Figure 6 As shown, the current-to-voltage conversion circuit 121 includes a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a second operational amplifier OP2. One end of the fourth resistor R4 is connected to the twisted-pair shielded cable 1 and one end of the fifth resistor R5. The other end of the fourth resistor R4 is connected to one end of the sixth resistor R6. The other end of the fifth resistor R5 is connected to the inverting input terminal of the second operational amplifier OP2 and one end of the seventh resistor R7. The other end of the sixth resistor R6 is connected to the non-inverting input terminal of the second operational amplifier OP2 and one end of the eighth resistor R8. The other end of the eighth resistor R8 is grounded. The other end of the seventh resistor R7 is connected to the output terminal of the second operational amplifier OP2 and the input terminal of the analog-to-digital converter 122.

[0043] Among them, the fourth resistor R4, the fifth resistor R5, the sixth resistor R6, the seventh resistor R7, and the eighth resistor R8 can be selected according to needs. For example, the fourth resistor R4 can be 100Ω, the fifth resistor R5 and the sixth resistor R6 can both be 10kΩ, and the seventh resistor R7 and the eighth resistor R8 can both be 22kΩ. See also Figure 6 The output voltage Vout = -(V1-V2) × R4 / R2, where V1-V2 is the voltage across the fourth resistor R4.

[0044] Figure 7 This is a structural block diagram of the communication system according to an embodiment of the present utility model.

[0045] like Figure 7 As shown, the communication system 100 includes: a host computer 30, a hub box 20, and the communication device 10 described in the above embodiment.

[0046] The host computer 30 can be located in the instrument room, and the junction box 20 can be located near the derrick of the logging system, with a considerable distance between them, such as 100 meters. Long-distance stable communication between the host computer 30 and the junction box 20 can be achieved by connecting them via the communication device 10.

[0047] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0048] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0049] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0051] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0052] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A communication device (10), characterized in that, The communication device (10) includes: The first conversion unit (11), adapted to connect to the hub box (20) of the logging system, is configured to receive the UART signal transmitted by the hub box (20) and convert it into a current signal; The second conversion unit (12) is connected to the first conversion unit (11) via a twisted-pair shielded cable (1) and is adapted to connect to a host computer (30). It is configured to receive the current signal transmitted by the twisted-pair shielded cable (1) and convert it into a USB signal, and to transmit the USB signal to the host computer (30).

2. The communication device (10) according to claim 1, characterized in that, The first conversion unit (11) includes: A first microcontroller (111), adapted to be connected to the hub box (20), is configured to receive UART signals transmitted by the hub box (20) and convert them into voltage signals; A digital-to-analog converter (112), connected to the first microcontroller (111), is configured to convert a voltage signal from digital form to analog form; A voltage-to-current conversion circuit (113), connected to the first microcontroller (111), is configured to convert a voltage signal in analog form into a current signal.

3. The communication device (10) according to claim 2, characterized in that, The voltage-to-current conversion circuit (113) includes a first resistor (R1), a first operational amplifier (OP1), and a switching transistor (T). The non-inverting input of the first operational amplifier (OP1) is connected to the digital-to-analog converter (112). The inverting input of the first operational amplifier (OP1) is connected to one end of the first resistor (R1) and the first end of the switching transistor (T). The output of the first operational amplifier (OP1) is connected to the control terminal of the switching transistor (T). The other end of the first resistor (R1) is grounded. The second end of the switching transistor (T) is connected to the twisted-pair shielded cable (1).

4. The communication device (10) according to claim 3, characterized in that, The voltage-to-current conversion circuit (113) further includes a second resistor (R2) and a third resistor (R3). The second resistor (R2) is connected between the non-inverting input terminal of the first operational amplifier (OP1) and the output terminal of the first microcontroller (111). The third resistor (R3) is connected between the output terminal of the first operational amplifier (OP1) and the control terminal of the switching transistor (T).

5. The communication device (10) according to claim 3 or 4, characterized in that, The switching transistor (T) is a P-type transistor.

6. The communication device (10) according to claim 2, characterized in that, The second conversion unit (12) includes: A current-to-voltage conversion circuit (121), connected to the twisted-pair shielded cable (1), is configured to convert the current signal transmitted by the twisted-pair shielded cable (1) into a voltage signal; An analog-to-digital converter (122), connected to the current-to-voltage conversion circuit (121), is configured to convert voltage signals from analog to digital form; The second microcontroller (123), connected to the analog-to-digital converter (122), is configured to convert the digital voltage signal into a UART signal; USB conversion chip (U), adapted to connect to the host computer (30), is configured to convert UART signals into USB signals and transmit them to the host computer (30).

7. The communication device (10) according to claim 6, characterized in that, The current-to-voltage conversion circuit (121) includes a fourth resistor (R4), a fifth resistor (R5), a sixth resistor (R6), a seventh resistor (R7), an eighth resistor (R8), and a second operational amplifier (OP2). One end of the fourth resistor (R4) is connected to the twisted-pair shielded cable (1) and one end of the fifth resistor (R5). The other end of the fourth resistor (R4) is connected to one end of the sixth resistor (R6). The other end of the fifth resistor (R5) is connected to the inverting input terminal of the second operational amplifier (OP2) and one end of the seventh resistor (R7). The other end of the sixth resistor (R6) is connected to the non-inverting input terminal of the second operational amplifier (OP2) and one end of the eighth resistor (R8). The other end of the eighth resistor (R8) is grounded. The other end of the seventh resistor (R7) is connected to the output terminal of the second operational amplifier (OP2) and the input terminal of the analog-to-digital converter (122).

8. The communication device (10) according to claim 6, characterized in that, The digital-to-analog converter (112) is integrated in the first microcontroller (111), and the analog-to-digital converter (122) is integrated in the second microcontroller (123).

9. The communication device (10) according to claim 1, characterized in that, The shielding layer of the twisted pair shielded cable (1) is grounded at one end connected to the second conversion unit (12) and suspended at the other end connected to the first conversion unit (11), and the length of the twisted pair shielded cable is greater than 40 meters.

10. A communication system (100), characterized in that, include: The junction box (20), the host computer (30), and the communication device (10) as claimed in any one of claims 1-9.

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