A transponder center point detection device and detection method

Abstract

A transponder center point detection device and method are disclosed. An "O"-type receiving antenna and an "8"-type receiving antenna in an antenna module simultaneously receive the uplink signal from the transponder. An XOR processing module performs a logical XOR operation on the output signals of the "O"-type and "8"-type receiving antennas. When the output of the XOR processing module is 1, an FM0 code generation module generates a "0x881D" codeword to modulate and encode the output signal of the XOR processing module. A digital circuit demodulation module performs code pattern determination on the received signal. The time corresponding to the "0x881D" codeword is the time when the transponder's center point is reached. This invention has low dependence on software algorithms, high reliability, strong anti-interference capability, and high credibility.

Description

Technical Field

[0001] This invention relates to a device and method for detecting the center point of a transponder. Background Technology

[0002] Transponder center point detection is a core function of the vehicle-mounted speed measurement and positioning control system in a BTM (balise transmission module) system. Currently, the following methods are commonly used to detect the center point position of the ground transponder:

[0003] The first method involves detecting the strength of the feedback signal from the activated transponder. The signal strength is highest at the center, representing the main lobe of the frequency domain signal. The peak value of the main lobe is then taken as the location of the center point. This method requires high-quality received transponder signals. Firstly, in practical applications, the shape of the main lobe may be irregular, making it difficult to distinguish from the side lobes. Secondly, the data processing algorithm is complex and requires adaptive adjustments based on the specific application.

[0004] The second method involves setting a specific threshold to determine the arrival and departure times of the received signal, and then using the center time of the arrival and departure as the center time point. This method is highly dependent on the selection of the threshold. If the threshold is set too high, the signal may not be recognized; if the threshold is set too low, interference signals may be collected, leading to misjudgment of the center position.

[0005] The third method addresses the challenge of measuring latency on the transmission link. Obtaining the center point location is a post-processing step. The detected signal is transmitted through the transmission path (e.g., coaxial cable) to filtering, amplification, signal conditioning modules, and finally to the algorithm. Path latency must be considered, typically through algorithmic compensation. This approach requires adjustments based on actual usage and demands sophisticated software algorithms.

[0006] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art. Summary of the Invention

[0007] The purpose of this invention is to provide a device and method for detecting the center point of a transponder, which has low dependence on software algorithms, high reliability, strong anti-interference ability.

[0008] To achieve the above objectives, the present invention provides a transponder center point detection device, comprising:

[0009] The antenna module includes an "O"-type receiving antenna and an "8"-type receiving antenna, wherein the "O"-type receiving antenna and the "8"-type receiving antenna respectively receive the uplink signal of the transponder;

[0010] The XOR processing module has its input terminal connected to the output terminal of the "O" type receiving antenna and the output terminal of the "8" type receiving antenna, and is used to perform a logical XOR operation on the output signal of the "O" type receiving antenna and the output signal of the "8" type receiving antenna.

[0011] An FM0 code generation module, whose input is connected to the output of the XOR processing module, is used to generate a specific code to modulate and encode the output signal of the XOR processing module.

[0012] The digital circuit demodulation module is used to determine the code pattern of the output signal of the FMO code generation module in order to identify the time when it passes the center point of the transponder.

[0013] The detection device also includes a differential processing module, whose input is connected to the output of the FMO code generation module, and whose output is connected to the digital circuit demodulation module via a differential cable. The differential processing module converts the output signal of the FMO code generation module into a differential signal and transmits it to the digital circuit demodulation module in a differential form.

[0014] The detection device also includes two filtering modules. The input of the filtering module is connected to the output of the "O" type receiving antenna or the "8" type receiving antenna, and its output is connected to the input of the XOR processing module. The filtering module is used to filter out signals.

[0015] The FMO code generation module uses a logic gate circuit shift register. A 70kHz clock is used as the input of the logic gate circuit shift register. The data input terminal of the logic gate circuit shift register is fixed by using pull-up and pull-down resistors.

[0016] The differential processing module uses a 485 interface chip to convert between single-ended and differential formats.

[0017] The present invention also provides a method for detecting the center point of a transponder, comprising:

[0018] The “O” type receiving antenna and the “8” type receiving antenna in the antenna module simultaneously receive the uplink signal from the transponder.

[0019] The XOR processing module performs a logical XOR operation on the output signals of the "O" type receiving antenna and the "8" type receiving antenna. When the signal has not passed the center point of the transponder, the phases of the "O" type receiving antenna and the "8" type receiving antenna are in phase, and the output of the XOR processing module is 0. When the signal has passed the center point of the transponder, the phases of the "O" type receiving antenna and the "8" type receiving antenna become out of phase, and the output of the XOR processing module is 1.

[0020] When the output of the XOR processing module is 0, the FM0 code generation module generates a normal clock pulse of 70KHz. When the output of the XOR processing module is 1, the FM0 code generation module generates the codeword "0x881D" to modulate and encode the output signal of the XOR processing module.

[0021] The digital circuit demodulation module performs code pattern judgment on the output signal of the FM0 code generation module, and the time corresponding to the code word "0x881D" is the time when it passes through the center point of the transponder.

[0022] The output signal of the FM0 code generation module is converted into a differential signal using a differential processing module, and then transmitted to the digital circuit demodulation module via a differential cable.

[0023] A filtering module was used to filter out the 27.095MHz signal frequency and its harmonics, leaving a 4.2MHz FSK signal.

[0024] This invention moves the detection process forward, identifying the time of passing the transponder's center point by judging the phase transition of the magnetic flux of the receiving antenna. The detection process is directly close to the object being measured, resulting in more reliable data. This invention uses physical hardware to generate FM0 codewords to modulate and encode the detection signal, eliminating reliance on algorithms and software processing, thus improving the reliability of the FM0 codewords. FM0 code patterns are well-suited for long-distance signal transmission. Encoding the center point time using a specific FM0 code pattern, while simultaneously employing differential transmission, effectively reduces interference in the transmission link, improves the anti-interference capability of the signal transmission link, lowers the performance requirements of the transmission cable, enhances the field adaptability of the transmission cable, and improves the reliability of the center point information. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the module structure of a transponder center point detection device provided by the present invention.

[0026] Figure 2 This is a schematic diagram of the receiving antenna in the antenna module receiving energy.

[0027] Figure 3 This is a schematic diagram of the FM0 code generation module. Detailed Implementation

[0028] The following is based on Figures 1-3 The preferred embodiments of the present invention will be described in detail below.

[0029] like Figure 1 As shown, the present invention provides a transponder center point detection device, which is installed on a train and includes:

[0030] Antenna module 1 obtains the time of passing through the transponder's center point by monitoring the phase transition of the magnetic flux of the receiving antenna. Antenna module 1 includes an "O"-type receiving antenna 101 and an "8"-type receiving antenna 102, which respectively receive the uplink signal from the transponder, such as... Figure 2 As shown, the horizontal axis represents time and the vertical axis represents power. When the "O" type receiving antenna 101 and "8" type receiving antenna 102 in the antenna module 1 have not passed the center point of the transponder, the coupling energy of the "O" type receiving antenna 101 shows an upward trend, and the magnetic flux of the "8" type receiving antenna 102 first increases and then decreases. When the center point of the transponder is reached, the coupling energy of the "O" type receiving antenna 101 reaches its peak, and the coupling energy of the "8" type receiving antenna 102 is 0. At this time, the phases of the two receiving antennas are the same. After passing the center point of the transponder, the coupling energy of the "O" type receiving antenna 101 shows a downward trend, and the coupling energy of the "8" type receiving antenna 102 will still first increase and then decrease. At this time, the phases of the magnetic fluxes coupled by the two receiving antennas are opposite.

[0031] Filtering module 2 is used to filter the output signals of the "O"-type receiving antenna 101 and the "8"-type receiving antenna 102. Filtering module 2 includes two identical filtering modules: the input of the first filtering module 201 is connected to the "O"-type receiving antenna 101, and the input of the second filtering module 202 is connected to the "8"-type receiving antenna 102. The first filtering module 201 and the second filtering module 202 use filters to remove the transmitted 27.095MHz signal frequency and its harmonics, leaving a 4.2MHz FSK signal. Then, signal conditioning is performed on the phase comparison output signals of the "O"-type receiving antenna 101 and the "8"-type receiving antenna 102.

[0032] The XOR processing module 3, whose input is connected to the output of the first filtering module 201 and the output of the second filtering module 202, is used to determine the time when the center point of the transponder is passed based on the phase change of the "O"-type receiving antenna 101 and the "8"-type receiving antenna 102. The XOR processing module 3 performs a logical XOR operation on the output signals of the "O"-type receiving antenna 101 and the "8"-type receiving antenna 102, and outputs the result through the XOR gate: when the antenna module 1 has not passed the center point of the transponder, the phases of the "O"-type receiving antenna 101 and the "8"-type receiving antenna 102 are in phase, and the output of the XOR processing module 3 is 0; when the antenna module 1 passes the center point of the transponder, the phases of the "O"-type receiving antenna 101 and the "8"-type receiving antenna 102 become out of phase, and the output of the XOR processing module 3 is 1. The moment when the output of the XOR processing module 3 changes from "0" to "1" is the time when the center point of the transponder is passed.

[0033] The FM0 code generation module 4, whose input is connected to the output of the XOR processing module 3, is used to modulate and encode the output signal of the XOR processing module 3. Figure 3 As shown, the FM0 code generation module 4 uses a logic gate circuit shift register. A 70KHz clock is used as the input of the logic gate circuit shift register. The data input terminal of the logic gate circuit shift register is fixed by pull-up and pull-down resistors. When the output of the XOR processing module 3 is 0, the FM0 code generation module 4 generates a normal 70KHz clock pulse. When the output of the XOR processing module 3 is 1, the FM0 code generation module 4 generates the codeword "0x881D". FM0 encoding is a specific codeword for long-distance transmission anti-interference.

[0034] The differential processing module 5, whose input is connected to the output of the FMO code generation module 4, converts the output signal of the FMO code generation module 4 into a differential signal, which is then transmitted to the digital circuit demodulation module 6 via a differential cable. In this embodiment, the differential processing module 5 uses a 485 interface chip for single-ended and differential conversion.

[0035] The digital circuit demodulation module 6, connected to the differential processing module 5 via a differential cable, is used to perform code pattern determination on the received signal to identify the time when it passes the center point of the transponder. In this embodiment, the digital circuit demodulation module 6 performs code pattern determination on the received signal through the corresponding 485 interface signal, and the time corresponding to the codeword "0x881D" is the time when it passes the center point of the transponder.

[0036] This invention moves the detection process forward, identifying the time of passing the transponder's center point by judging the phase transition of the magnetic flux of the receiving antenna. The detection process is directly close to the object being measured, resulting in more reliable data. This invention uses physical hardware to generate FM0 codewords to modulate and encode the detection signal, eliminating reliance on algorithms and software processing, thus improving the reliability of the FM0 codewords. FM0 code patterns are well-suited for long-distance signal transmission. Encoding the center point time using a specific FM0 code pattern, while simultaneously employing differential transmission, effectively reduces interference in the transmission link, improves the anti-interference capability of the signal transmission link, lowers the performance requirements of the transmission cable, enhances the field adaptability of the transmission cable, and improves the reliability of the center point information.

[0037] It should be noted that, in the embodiments of the present invention, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "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 the embodiments. They do not 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 the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0038] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," 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. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] It should be understood that, when used in this specification and the appended claims, the term "comprising" indicates the presence of the described feature, integral, step, operation, element and / or component, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0040] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0041] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0042] As used in this specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrases "if determined" or "if [described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [described condition or event] is detected," or "in response to detection of [described condition or event]."

[0043] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention. After reading the above content, various modifications and substitutions to the present invention will be obvious to those skilled in the art. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A transponder center point detection device, characterized in that, Include: The antenna module includes an "O"-type receiving antenna and an "8"-type receiving antenna, wherein the "O"-type receiving antenna and the "8"-type receiving antenna respectively receive the uplink signal of the transponder; The XOR processing module has its input terminal connected to the output terminal of the "O" type receiving antenna and the output terminal of the "8" type receiving antenna, and is used to perform a logical XOR operation on the output signal of the "O" type receiving antenna and the output signal of the "8" type receiving antenna; An FM0 code generation module, whose input is connected to the output of the XOR processing module, is used to generate a code that modulates and encodes the output signal of the XOR processing module. A digital circuit demodulation module is used to determine the code pattern of the output signal of the FMO code generation module in order to identify the time when the transponder's center point is passed. The differential processing module has its input connected to the output of the FMO code generation module and its output connected to the digital circuit demodulation module via a differential cable. The differential processing module converts the output signal of the FMO code generation module into a differential signal and transmits it to the digital circuit demodulation module in a differential form.

2. The transponder center point detection device as described in claim 1, characterized in that, The detection device also includes two filtering modules. The input of the filtering module is connected to the output of the "O" type receiving antenna or the "8" type receiving antenna, and its output is connected to the input of the XOR processing module. The filtering module is used to filter out signals.

3. The transponder center point detection device as described in claim 1, characterized in that, The FMO code generation module uses a logic gate circuit shift register. A 70kHz clock is used as the input of the logic gate circuit shift register. The data input terminal of the logic gate circuit shift register is fixed by using pull-up and pull-down resistors.

4. The transponder center point detection device as described in claim 1, characterized in that, The differential processing module uses a 485 interface chip to convert between single-ended and differential formats.

5. A method for detecting the center point of a transponder using the transponder center point detection device as described in any one of claims 1-4, characterized in that, Include: The "O" type receiving antenna and the "8" type receiving antenna in the antenna module simultaneously receive the uplink signal from the transponder. The XOR processing module performs a logical XOR operation on the output signals of the "O" type receiving antenna and the "8" type receiving antenna. When the signal has not passed the center point of the transponder, the phases of the "O" type receiving antenna and the "8" type receiving antenna are in phase, and the output of the XOR processing module is 0. When the signal has passed the center point of the transponder, the phases of the "O" type receiving antenna and the "8" type receiving antenna become out of phase, and the output of the XOR processing module is 1. When the output of the XOR processing module is 0, the FM0 code generation module generates a normal clock pulse of 70KHz. When the output of the XOR processing module is 1, the FM0 code generation module generates the codeword "0x881D" to modulate and encode the output signal of the XOR processing module. The digital circuit demodulation module performs code pattern judgment on the output signal of the FM0 code generation module, and the time corresponding to the code word "0x881D" is the time when it passes through the center point of the transponder.

6. The transponder center point detection method as described in claim 5, characterized in that, The output signal of the FM0 code generation module is converted into a differential signal using a differential processing module, and then transmitted to the digital circuit demodulation module via a differential cable.

7. The transponder center point detection method as described in claim 5, characterized in that, A filtering module was used to filter out the 27.095MHz signal frequency and its harmonics, leaving a 4.2MHz FSK signal.

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