CN109374150B

CN109374150B - Swallowing type capsule monitoring device

Info

Publication number: CN109374150B
Application number: CN201811491660.9A
Authority: CN
Inventors: 刘昌荣; 张钰狄; 刘学观
Original assignee: Suzhou University
Current assignee: Suzhou University
Priority date: 2018-12-07
Filing date: 2018-12-07
Publication date: 2023-09-22
Anticipated expiration: 2038-12-07
Also published as: CN109374150A

Abstract

The invention provides a swallow type capsule monitoring device, which comprises a shell, wherein an antenna assembly, a control module, a sampling module and a power supply module are arranged in the shell, the antenna assembly comprises a first layer and a second layer which is arranged in parallel with the first layer; the system comprises a sampling module, a control module, an antenna assembly and a receiving device, wherein the sampling module is used for sampling an object (temperature) to be monitored at intervals and feeding back sampling information to the connected control module, the control module is used for receiving the sampling information and converting the sampling information and then outputting the sampling information to the antenna assembly, and the antenna assembly is used for receiving the information transmitted by the control module and transmitting the information to the receiving device. The swallow type capsule monitoring device is small in size, a miniaturized antenna is arranged in the swallow type capsule monitoring device, a control module, a power supply module, an antenna assembly and the like comprising a chip are integrated into the capsule, and the temperature of an object to be detected is monitored and transmitted outwards in real time during operation. The device is low in data transmission loss during operation, and in addition, the antenna component uses FR4 boards to reduce the total cost of the antenna.

Description

Swallowing type capsule monitoring device

Technical Field

The invention relates to a monitoring device, in particular to a swallow type capsule body temperature monitoring device.

Background

The rapid development of wireless information technology brings about several changes to human life style and information acquisition means. Currently, wireless information technology occupies a very important position in national economy. Similarly, in the biomedical field, new technologies based on mobile interconnection, wireless medical devices, big data and the like are rapidly subverting the current situation of the medical field, and in the medical field which is rapidly developed, the combination of these technologies and business models is comprehensively subverting the current situation and development of the prior art of the cognitive architecture of medical treatment, documents [ Xie Xiang, zhang Chun, wang Zhihua. Implantable electronic systems in biomedicine. Electronic journal, vol.32, no.3, pp.462-467,2004].

In biomedical, wireless data transmission refers to implanting an antenna into a monitored object, transmitting acquired data by using the implanted antenna, and receiving the data through an external antenna to monitor the health condition (such as body temperature, heart rate, etc.) of the monitored object. The implanted antenna is therefore wireless dataOne of the key components of transmission is that the size, operating efficiency, frequency, polarization, etc. of the implanted antenna have a great influence on the transceiving link, thereby affecting the transmission distance and operating time limit of the implanted device. Because the implanted antenna has compact structure, complex internal tissue structure of the monitored object, high dielectric constant, non-uniformity, high loss and other characteristics, and factors such as the size, the working bandwidth, the radiation efficiency, the system compatibility, the safety of the monitored object and the like of the antenna need to be considered in the design process, how to design the high-performance miniaturized implanted antenna is the current research difficulty and the hot spot document [1, chen Weigong Yang Yimin She Shuming ], the research of an implanted low-power wireless system for monitoring small animals, a sensor and a microsystem, vol.31, no.4, pp.60-62,2012; 2, wu, implanted micro antenna design, university of chinese academy of sciences's university of s treatises, 2013.]. Duan, literature [ Z.Duan, Y.X.Guo, R.F.Xue, M.Je, and D.L. Kwong, "differential-fed Dual-band implantable antenna for biomedical applications," IEEE Trans. Antenna s Propag, vol.60, no.12, pp.5587-5595, dec.2012.]The team studied a differential dual-band implantable antenna with operating frequencies 433.9MHz and 542.4MHz, close to the MICS (medical implant communication service) frequency band of 402-405MHz, implementing a dual-band operating mode by generating two current paths. The antenna dimensions are 27mm x 14mm x 1.27mm, and the background size of the implant application is obviously too large for the monitored object. This team improved implantable antennas, literature [ Z.Duan, Y.X.Guo, M.Je, and D.L. Kwong, "Design and in Vitro Test of a Differentially Fed Dual-Band Implantable Antenna Operating at MICS and ISM Bands," IEEE Trans. Antenna s production, vol.62, no.5, pp.2430-2439, may 2015.]By loading the short-circuit nails, miniaturization is realized in a mode of slotting on the ground in a large area, miniaturization is realized as well, and performance test after antenna conformal is performed. However, this method has disadvantages, and the manner of loading the shorting pin not only increases the processing cost, but also affects the front end rf circuit. And the ground slotting can cause energy leakage, and the influence of a circuit is large, so that the performance is unstable. Merli, literature [ F.Merli, L.Bolomey, J. -F.Z urcher, G.Corradini,E.Meurville,and A.K.Skrivervik,“Design,realization and measurements of a miniature antenna for implantable wireless communication systems,”IEEE Trans.Antennas Propag.,vol.59,no.10,pp.3544-3555,Oct.2011.]The proposed conformal dual-band antenna operates in the Medradio (401-406 MHz) and ISM bands (2.4-2.5 GHz). The antenna is similar to a PIFA antenna, gains are-28.8 dBi and-18.5 dBi respectively, and the gains are less influenced by surrounding circuits, but the antenna is fused into a capsule, so that the specification of the capsule reaches 32.1mm multiplied by 10mm, and the size of the capsule is too large. Document [ Rupam Das, and Hyoungsuk Yoo, "A Wideband Circularly Polarized Conformal Endoscopic Antenna System for High-Speed Data Transfer", IEEE Trans. Antenna s Propag, vol.65, no.6, pp.2816-2826, apr.2017]The circularly polarized conformal antenna proposed by r.das, which operates at 915MHz, is miniaturized by slotting the radiating patch and the ground and using two long arms. The conformal back dimension of the antenna is only 66.7mm ³ The design specification is theoretically incorporated into a capsule of 26mm×11mm, but there is a need for further improvement in stability.

Disclosure of Invention

In order to solve the technical problems, the invention aims at: a swallow capsule monitoring device is provided. The capsule detection device monitors the temperature of a detected object and transmits sampled information (such as temperature information) to a matched receiving device in real time, and has small volume and low cost.

In order to achieve the above purpose, the invention adopts the following technical scheme:

the swallow type capsule monitoring device is characterized by comprising a shell, wherein the shell internally comprises an antenna assembly, a control module, a sampling module and a power supply module, and the antenna assembly comprises a first layer and a second layer which is arranged in parallel with the first layer; the system comprises a sampling module, a control module, an antenna assembly and a control module, wherein the sampling module is used for sampling information of a monitored object at intervals and feeding back the sampling information to the connected control module, the control module is used for receiving the sampling information fed back by the sampling module, converting the sampling information and outputting the converted sampling information to the antenna assembly, and the antenna assembly is used for receiving the information transmitted by the control module and transmitting the information outwards.

Preferably, the shell comprises a polyether-ether-ketone material or a sub-power material in a capsule shape, the impedance of the antenna component is conjugate matched with the output impedance of the chip of the control module, and the antenna component receives the information transmitted by the control module and transmits the information to a receiving device in matched connection. The size of the capsule is 11mm (diameter) multiplied by 16mm (length), and the size requirement of the monitored object is met.

Preferably, the first layer comprises a first dipole, said first dipole being bilaterally symmetric along a midline, said first layer comprising a first end and a second end; the second layer comprises a second dipole which is bilaterally symmetrical along a central line, the second layer comprises a third end part and a fourth end part, the third end part is electrically connected with the first end part, the fourth end part is electrically connected with the second end part, and the middle part of the second layer further comprises a strip-shaped parasitic strip.

Preferably, the width of the second dipole is greater than the width of the first dipole.

Preferably, the width of the parasitic stripe is greater than the width of the second dipole.

Preferably, the ratio of the width of the parasitic stripe to the width of the second dipole is between 1.2 and 5.0.

Preferably, the sampling module comprises a substrate, and a sensor mounted on one side of the substrate.

Preferably, a thermally conductive material is applied between the sensor and the housing.

Preferably, the sampling module is configured at one end of the monitoring device, and the antenna assembly is configured at the other end of the monitoring device; the power supply module comprises an energy storage battery.

Preferably, the substrate of the sampling module is parallel to the antenna assembly.

Compared with the prior art, the invention has the advantages that:

the swallow type capsule detection device provided by the invention is provided with the miniaturized antenna inside, and integrates a chip, a power supply module, an antenna module and the like into the capsule, so that the layout of components is ensured not to influence the performance of the whole circuit, and the capsule detection device monitors the temperature of an object to be detected and transmits the temperature in real time. The loss of data transmission is low. The size of the capsule detection device is small to meet the requirement of the detected object.

Drawings

The invention is further described below with reference to the accompanying drawings and examples:

FIG. 1 is a schematic diagram of functional modules of a monitoring device according to an embodiment of the present invention;

FIG. 2a is a schematic diagram of a first layer structure of an antenna of a monitoring device according to an embodiment of the present invention;

FIG. 2b is a schematic diagram of a second layer structure of an antenna of the monitoring device according to the embodiment of the present invention;

FIG. 3 is a topology of a transmit module of a monitoring device according to an embodiment of the present invention;

FIG. 4 is a topology diagram of a receiving module matching a monitoring device of an embodiment of the present invention;

FIG. 5 is a schematic diagram of an application of a monitoring device according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of an antenna of a monitoring device according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a simulation direction of an antenna of a monitoring device according to an embodiment of the present invention;

FIG. 8 is a schematic diagram illustrating an application of a monitoring device and an external receiving device according to an embodiment of the present invention;

fig. 9 is a schematic diagram of an internal structure of a monitoring device according to an embodiment of the present invention.

Detailed Description

The objects, technical solutions and advantages of the present invention will become more apparent by the following detailed description of the present invention with reference to the accompanying drawings. It should be understood that the description is only illustrative and is not intended to limit the scope of the invention. In addition, in the following description, descriptions of well-known structures and techniques are omitted so as not to unnecessarily obscure the present invention.

Examples:

fig. 1 shows a swallow capsule monitoring device according to an embodiment of the present invention, where the capsule monitoring device 100 includes an antenna assembly 101, a control module 102, a sampling module 103, and a power supply module 104, where the sampling module 103 samples an object to be monitored at intervals of time t (specific to an application scenario set, such as 100ms,200ms, etc.), and feeds back sampling information to a connected control module 102, the control module 102 receives the sampling information and converts the sampling information to output to the antenna assembly 101, and the antenna assembly 101 receives information transmitted by the control module 102 and transmits the information to a matched receiving device (not shown). In the embodiment, the monitoring device is designed into a capsule shape, the shell of the monitoring device is made of PEEK (polyether ether ketone) material, two symmetrical halves are formed by using a 3D printing technology, and then the monitoring device is in bayonet butt joint, so that the monitoring device is consistent with a processing method of actual capsule pills. The matched receiving device adopts a dipole antenna for receiving, and the chip is the same as that used by the transmitting device.

Fig. 2a and b show a schematic structure of the antenna assembly 101. Next, an antenna assembly 101 is described in connection with fig. 2a,2b, comprising a first layer 101a (also referred to as an upper layer) and a second layer 101b (also referred to as a lower layer). The first layer 101a includes a first dipole 101a1, the dipole 101a1 being bilaterally symmetrical along a center line (y direction), and a bottom portion of the first layer 101a having two end portions (first end portion, second end portion) 101a3,101a2. The second layer 101b includes a second dipole 101b1, and the dipole 101b1 is bilaterally symmetrical along a center line (y direction). The second layer 101b has two end portions (third end portion, fourth end portion) 101b3,101b4. The middle portion thereof further includes a parasitic stripe 101b2. In this embodiment, the dipole 101a1 of the first layer 101a is different from the width 101b1 of the dipole under the second layer 101 b. Preferably, the width of the dipole 101a1 of the first layer 101a is greater than the width of the dipole 101b1 under the second layer 101 b. The middle portion of the second layer 101b2 of this embodiment is further configured with a parasitic stripe for adjusting the real impedance of the antenna. Preferably, the ratio of the width of the parasitic strip 101b2 to the width of the second layer dipole 101b1 is 1.2-5.0 (e.g., 1.2,2,3,4,4.5,5), which is used to adjust the real impedance of the antenna. In the model simulation, the dielectric constant of the surrounding environment tissue is 55, the conductivity is 0.948, and the capsule model also needs to be co-designed to simulate the real environment so as to reduce the error of the antenna performance in practical application. In the design of the antenna component, the first layer and the second layer are disc-shaped, laminated dipoles are adopted to reduce the space occupied by the antenna in a capsule, the working frequency range of the antenna is 902-928MHz (ISM frequency range), the antenna component is composed of two layers of dielectric substrates, the dielectric constants of the two layers of dielectric substrates are 4.4, the loss tangent of the dielectric substrates is 0.02, and the thickness of the dielectric substrates is 0.8mm of FR4 board. The antenna component adopts a differential feed mode, and the antenna impedance is designed to be conjugate matched with the chip impedance, so that a matching circuit is omitted, and the miniaturization of the capsule system is realized.

Since the circuit portion employs a chip having a pair of differential rf outputs, its output impedance operating at 915MHz is (86.5+j43) Ω.

Fig. 3 is a schematic diagram of the topology of the transmitting modules in the control module 102. Wherein, C2021-C2017 are decoupling capacitors, 2030, 2032,2033 form 26MHz crystal oscillator, 2034,2035,2036 form 32.76KHz crystal oscillator, and the decoupling capacitors are connected between the power line and the ground of the CC1110 wireless transceiver circuit shown in FIG. 3, which has three functions: the first is an energy storage capacitor used as a circuit; filtering high-frequency noise generated by the device, and cutting off a path of the high-frequency noise propagating through a power supply loop; thirdly, noise carried by the power supply is prevented from interfering the circuit. High frequency switching noise generated by the active device when switching will propagate along the power line. In the design, in order to filter out low-frequency signals and high-frequency signals well, a large-capacitance and small-capacitance mode is adopted for design. The small capacitor adopts a capacitor combination of 100nF and 220pF, which is beneficial to filtering high-frequency signals. The filtering effect can be achieved by adding 1uF and 2.2uF of the high-frequency removing capacitor at the place where the power supply VCC enters the board.

The crystal oscillator of the CC1110 wireless receiving and transmitting circuit is as follows: 2030 2032,2033 is a 26MHz crystal oscillator, which provides a clock frequency for the system, 2034,2035,2036 is a 32.768kHz crystal oscillator, for a sleep timer. The CC1110 has four power management modes (PM 0-PM 3), with different crystal oscillators for different modes, allowing fast switching between the four power management modes to reduce the power consumption of the system. When the module is in the working state, the module is in a PM0 mode, the master clock 26MHz crystal oscillator works, and the current consumption values when receiving and transmitting data are respectively 22mA and 31mA under the condition that 10dbm is taken as the transmitting power. When the wireless module is in PM1 and PM2 states, the 32.768kHz crystal oscillator clock works. When the wireless module is in the idle state, the module is in PM3 mode and the internal clocks are all off. Table 1 lists the current consumption of the wireless module in various modes. Table 1 lists the current consumption of the wireless module in various modes.

Table 1.Cc1110 four modes of operation

Fig. 4 is a schematic topology diagram of a receiving module of the matching monitoring device. The receiving module further comprises a radio frequency front end comprising a balun transformation and a low pass filter. The transceiver circuit based on the CC1110 comprises a transmitting module, a bottom plate module and a small-size antenna, wherein the core of the transmitting module is a low-power-consumption radio frequency chip CC1110 of TI company, an enhanced 8051MCU IP core is embedded in the chip, and the operation processing capacity is more than 8 times of that of 8051. Since the output ports of the CC1110F32 chip are two differential output, i.e. two output ports with opposite phases and equal amplitude, the two ports must be converted into a matching port with 50 ohms by using a Balun circuit, and the matching port is output to the antenna end for transmission. And combining factors such as plates, sizes, frequencies and the like, carrying out overall hardware design by using three-dimensional electromagnetic simulation software such as HFSS, CST and the like, and finally carrying out ADS overall simulation verification to ensure that radio frequency loss is the lowest and realize efficient emission.

The Balun circuit, i.e., the Balun circuit (Balance to Unbalance Transfer), functions to transform the balanced output (differential output) of the chip to a single-ended matched load. Because the output differential ports have the characteristics of equal amplitude and opposite phases, the Balun transformation circuit not only needs to provide 180-degree inversion, but also needs to reduce loss as much as possible and improve the output power of a single port. Likewise, balun acts as an input port for the receiver, as well as a certain impedance matching and improves the receiver sensitivity. The Balun transformation circuit has the characteristics of excellent performance and compact structure, and is particularly suitable for a radio frequency transceiver system with higher integration level. The lumped element Balun transformation circuit adopts a design method of combining a low-pass filter and a high-pass filter, so that the phase shift of +/-90 degrees of each circuit is overlapped to form two 180-degree phase differences.

Because the CC1110F32 chip is internally integrated with the power amplifier, through automatic gain control AGC, the internal power amplifier can output radio frequency signals with different powers according to the requirements of users, however, the efficient operation of the power amplifier often accompanies the nonlinear effect, thereby generating higher harmonic components, and returning to the crystal oscillator to deteriorate the modulation of the transceiver. The low-pass filter is used for filtering out electromagnetic waves in a specific frequency band, filtering out noise interference signals returned to the receiving and transmitting system and improving the performance of radio frequency receiving and transmitting.

In the above embodiment, the singlechip control chip of the transmitting module/receiving module adopts the CC1110 chip of TI, and the chip is a low-power-consumption system-on-chip with 8-12 bit analog-to-digital conversion module and working below 1 GHz. In operation, only 20mA of current is consumed at a transmit power of-6 dBm, the chip having a pair of differential RF ports. The package size (6 mm×6 mm) meets the size requirement to be tested.

Sampling module 103 preferably employs a temperature sensor. In the embodiment, the model LMT70 of TI is adopted, and the precision can reach +/-0.05 ℃ within the temperature range of 20-42 ℃. The current consumption is low in operation, and is only 9.2 mu A in normal operation. The small package size (0.88 mm x 0.88 mm) thus facilitates optimization of the capsule volume. In one embodiment, the sampling module is disposed at the top end of the capsule, such that the sampling module (temperature sensor) collects information (e.g., temperature) around the outside, and feeds the sampled information back to the control module, such that the processor (analog-to-digital conversion of the single-chip microcomputer) of the control module processes and transmits the information wirelessly. The information received by the receiving module of the matched receiving side is displayed by a connected display device (such as an LCD display screen). In other embodiments, the sampling module is an RTD (resistance temperature detector), an NTC/PTC thermistor, or the like, as long as the temperature information of the monitored object can be accurately sampled.

As shown in FIG. 5, the antenna simulation diagram of the monitoring device adopts a single-layer muscle tissue model to simulate the external human body environment, and the size of the model is 100×100×130mm ³ . As shown in fig. 5, at the 915MHz frequency point, the electrical parameter characteristic of the muscle is er=56.87, σ=0.8S/m, and the implantation depth thereof is 50mm. In this embodiment, the capsule has a specification of 11mm (diameter) ×16mm (length). Through simulation optimization, the specific dimensions of the antenna assembly are as follows: l, l ₁ ＝0.6mm，l ₂ ＝8.37mm，l ₃ ＝6.17mm，l ₄ ＝0.8mm，l ₅ ＝8.3mm,l ₆ ＝10.8mm w ₁ ＝0.5mm，w ₂ ＝0.3mm，R ₁ ＝0.3mm，x _f ＝-0.5mm，y _f -4.55mm, α=170°, β=164°. The working principle is as follows: in the simulation model of the differential feed mode, the two ports are equal in amplitude and 180 ° out of phase. The reflection coefficient of a differential antenna is typically measured as a differential reflection coefficient. Due to the complex impedance of the antenna, the differential reflection coefficient is redefined as:

za=ra+j×xa is the input impedance of the antenna, and zc=rc+j×xc is the chip input impedance. If conjugate matches are available, ra should equal Rc and Xa should equal Xc. The antenna is miniaturized mainly by effectively prolonging a current path through a laminated dipole, in the implementation process, the antenna impedance and the chip output impedance are subjected to conjugate matching by adopting a conjugate matching technology, so that the miniaturization of the capsule volume is realized, and in the antenna, the required complex impedance is realized by adjusting the line width of the dipole and the width of a lower middle parasitic strip: (86.5-j 43) Ω, in this embodiment α and β mainly affect the resonant frequency of the antenna. In the xoy plane, the antenna has omnidirectional radiation characteristics, so that the antenna is more favorable for radiation to the periphery without being limited by different positions of a monitored object (sometimes called a detected object) of a capsule, and the gain is-27.8 dBi.

Fig. 6 shows a simulation of the reflection coefficient and impedance of the antenna of the monitoring device. As can be seen from the graph, the simulated-10 dB impedance bandwidth reaches 16MHz, and the simulated impedance is (86.28-j.42.3) omega.

Fig. 7 is a schematic diagram showing the simulation directions of the antennas of the monitoring device, i.e., the main polarization and cross polarization patterns of the E-plane and the H-plane. It can be seen from the figure that the cross polarization of the differential antenna is weak. The antenna is omni-directional and can radiate well no matter what direction or position the capsule is in the monitored object (human body).

The schematic diagram of the connection between the external receiving device and the monitoring device in different directions, which is matched with the schematic diagram shown in fig. 8, is that the external receiving device is placed in a distance with the monitored object as the center and the radius of 2m, so that the temperature in the monitored object can be received.

FIG. 9 is an interface schematic of a monitoring device according to an embodiment of the present invention. The swallow type capsule monitoring device 1000 comprises a housing 1005, an antenna assembly 1001, a control module 1002, a sampling module 1003 and a power supply module 1004, wherein the antenna assembly 1001 comprises a first layer 1001a and a second layer 1001b, the first layer 1001a and the second layer 1001b are arranged in parallel, the connection ends of the antenna assembly 1001a and the second layer 1001b are respectively and electrically connected to the control module 1002 (connected to a preset end of the control module 1002) through connection parts 1001c1 and 1001c2, and the control module 1002 is electrically connected to the power supply module 1004; the sampling module 1003 includes a substrate 1003b, a sensor 1003a, and the sensor 1003a is mounted on one side of the substrate 1003 b. Preferably, the sensor 1003a is mounted to one side of the substrate 1003b by a Surface Mount (SMT) format. In this way, the sampling modules 1003 sample the monitored object at intervals (time t, and feed the sampling information back to the connected control module 1002, the control module 1002 receives the sampling information and outputs the converted information to the antenna assembly 1001, and the antenna assembly 1001 receives the information transmitted by the control module 1002 and transmits the information to a matched receiving device.

In the present embodiment, the sampling module 1003 is disposed at one end of the monitoring device, and the antenna assembly 1001 is disposed at the other end of the monitoring device, that is, the sampling module is not disposed on the same side as the antenna assembly, so that the detection accuracy of the sampling module is improved. In this embodiment, the power supply module includes an energy storage battery, such as a button battery.

In one embodiment, the substrate of the sampling module is substantially parallel to the antenna assembly (or the substrate is substantially at an angle of less than 10 ° to the antenna assembly, such that it appears that the substrate of the sampling module is parallel to the antenna assembly), which improves sampling accuracy.

In one embodiment, the ends of the first layer 1001a are soldered to the ends of the second layer 1001b, i.e. the feeding points of the antenna assembly, which are connected to the rf ends of the circuit board with coaxial wires, respectively.

In one embodiment, the device housing is a PEEK material.

In one embodiment, the internal temperature sensor of the device is responsible for collecting the external ambient temperature of the monitored object, processing the data by the micro-control processor and sending the data, and the receiving module matched with the device sends the received temperature data to a connected display (such as an LCD display screen) through a serial port. Preferably, in the receiving module, a dipole with a half wavelength is used as the receiving antenna.

In one embodiment, a thermally conductive material is coated between the sensor and the housing.

The antenna assembly in the above embodiments is sometimes referred to as an antenna.

It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explanation of the principles of the present invention and are in no way limiting of the invention. Accordingly, any modification, equivalent replacement, improvement, etc. made without departing from the spirit and scope of the present invention should be included in the scope of the present invention. Furthermore, the appended claims are intended to cover all such changes and modifications that fall within the scope and boundary of the appended claims, or equivalents of such scope and boundary.

Claims

1. The swallow type capsule monitoring device is characterized by comprising a shell, wherein the shell internally comprises an antenna assembly, a control module, a sampling module and a power supply module, and the antenna assembly comprises a first layer and a second layer which is arranged in parallel with the first layer; the sampling module samples the information of the monitored object at intervals and feeds the sampled information back to the connected control module, the control module receives the sampled information fed back by the sampling module and outputs the sampled information to the antenna assembly after converting the sampled information, the antenna assembly receives the information transmitted by the control module and transmits the information outwards, the impedance of the antenna assembly is conjugate matched with the output impedance of the chip of the control module,

the first layer comprises a first dipole, the first dipole is symmetrical left and right along a central line,

the first layer includes a first end and a second end;

the second layer comprises a second dipole which is symmetric left and right along a central line, the second layer comprises a third end part and a fourth end part, the third end part is electrically connected with the first end part, the fourth end part is electrically connected with the second end part, the middle part of the second layer also comprises a strip-shaped parasitic strip, the width of the second dipole is larger than that of the first dipole,

the width of the parasitic strip is larger than the width of the second dipole, the ratio of the width of the parasitic strip to the width of the second dipole is 1.2-5.0,

the first layer and the second layer are respectively disc-shaped, and the laminated dipoles are adopted to reduce the space occupied by the antenna in the capsule, the working frequency range of the laminated dipole antenna is 902-928MHz ISM frequency range, and the laminated dipole antenna is composed of two layers of medium substrates.

2. The monitoring device of claim 1, wherein the housing comprises a capsule of polyetheretherketone material or a sub-dak material, and the antenna assembly receives the information transmitted by the control module and transmits to a mating connection receiving device.

3. The monitoring device of claim 1, wherein the sampling module comprises a substrate, and a sensor mounted to one side of the substrate.

4. A monitoring device according to claim 3, wherein a thermally conductive material is applied between the sensor and the housing.

5. The monitoring device of claim 3, wherein the sampling module is disposed at one end of the monitoring device and the antenna assembly is disposed at the other end of the monitoring device; the power supply module comprises an energy storage battery.

6. The monitoring device of claim 1, wherein the substrate of the sampling module is parallel to the antenna assembly.