CN205354044U - Radiofrequency signal audiomonitor - Google Patents
Radiofrequency signal audiomonitor Download PDFInfo
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- CN205354044U CN205354044U CN201521112642.7U CN201521112642U CN205354044U CN 205354044 U CN205354044 U CN 205354044U CN 201521112642 U CN201521112642 U CN 201521112642U CN 205354044 U CN205354044 U CN 205354044U
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Abstract
The utility model provides a radiofrequency signal audiomonitor, include: antenna, radio frequency front end module and control module, it acquires radiofrequency signal through the antenna, then is intermediate frequency signal by the radio frequency front end module with the radiofrequency signal down coversion to be baseband signal with the intermediate frequency signal demodulation, handle baseband signal decode by processing module again, and the baseband signal after will decoding sends for the host computer, thereby realized the monitor to radiofrequency signal in the RFID system. The radiofrequency signal audiomonitor that this embodiment provided is small, with low costs, can satisfy RFID field research staff, the on -the -spot personnel of the application demand to portable agreement test equipment.
Description
Technical field
This utility model relates to communication technical field, particularly relates to a kind of radiofrequency signal audiomonitor.
Background technology
Superfrequency (UltraHighFrequency, UHF) RF identification (RadioFrequencyIdentification, RFID) system is generally made up of read write line, label and application layer software.Its basic functional principle is: after label enters read write line radiation areas, receive the radiofrequency signal that read write line sends, rely on radio frequency signal demodulator energy supply and send out the information (passive label) being stored in chip, or, storage information (active label) in the chips is actively sent by label, after read write line receives label information, valid data are given application layer software and processes.
When exploitation test or on-the-spot application problem process, it is often necessary to analyze the interaction data between read write line and label.For the data that label sends, generally can resolve via read write line and show again through man-machine interface.And label is owing to encapsulation integrated level is higher and does not have external interface, generally cannot be used for monitoring the data that read write line end sends.
Signal analyzer RFID protocol of arranging in pairs or groups is used to resolve option, it is possible to the RFID radiofrequency signal in Direct Acquisition space.But, the general volume weight of signal analyzer is unsuitable for more greatly on-the-spot application testing, and involves great expense and cannot allot in a large number to on-the-spot test personnel.
Utility model content
For the drawbacks described above of prior art, this utility model provides the radiofrequency signal audiomonitor that a kind of volume is little, cost is low.
This utility model provides a kind of radiofrequency signal audiomonitor, including: antenna, RF front-end module and processing module, RF front-end module is connected with antenna and processing module respectively；Wherein,
Antenna, is used for obtaining radiofrequency signal；
RF front-end module, for radiofrequency signal down-converts to intermediate-freuqncy signal, and is demodulated into baseband signal by intermediate-freuqncy signal；
Processing module, for being decoded baseband signal processing, and is sent to host computer by decoded baseband signal.
In an embodiment of the present utility model, antenna specifically includes: medium substrate, radiating element, feeder line and earth plate；
Radiating element and feeder line are positioned at the upper surface of medium substrate, and earth plate is positioned at the lower surface of medium substrate；
Radiating element includes multiple parallel microstrip line and multiple vertical microstrip line, and parallel microstrip line is arranged alternately formation S shape foldable structure with vertical microstrip line；Radiating element end is electrically connected with feeder line by vertical microstrip line, and the vertical microstrip line of radiating element end is positioned at the middle part of medium substrate.
In an embodiment of the present utility model, RF front-end module specifically includes: local oscillator, frequency mixer and cymoscope, and the input of frequency mixer is connected with local oscillator and antenna respectively, and the outfan of frequency mixer is connected with cymoscope；
Local oscillator, is used for producing local oscillated signal；
Frequency mixer, for being mixed radiofrequency signal and local oscillated signal, to produce intermediate-freuqncy signal；
Cymoscope, for being demodulated into baseband signal by intermediate-freuqncy signal.
In an embodiment of the present utility model, RF front-end module also includes: radio frequency band filter and low-noise amplifier, and antenna, radio frequency band filter, low-noise amplifier and frequency mixer are sequentially connected with；
Radio frequency band filter, for being filtered radiofrequency signal；
Low-noise amplifier, is used for amplifying filtered radiofrequency signal.
In an embodiment of the present utility model, RF front-end module also includes: intermediate-frequency filter and baseband processing circuitry；
Intermediate-frequency filter is connected between local oscillator and cymoscope, for intermediate-freuqncy signal is filtered；
Baseband processing circuitry is connected with cymoscope, for baseband signal being filtered and threshold judgement process.
In an embodiment of the present utility model, cymoscope is logarithmic detector.
In an embodiment of the present utility model, RF front-end module is provided with intermediate-freuqncy signal interface and baseband signal interface；Intermediate-freuqncy signal interface is connected with intermediate-frequency filter, and baseband signal interface is connected with baseband processing circuitry.
In an embodiment of the present utility model, processing module is connected with local oscillator, and processing module is additionally operable to control the frequency of the local oscillated signal that local oscillator produces.
The radiofrequency signal audiomonitor that this utility model embodiment provides, radiofrequency signal is obtained by antenna, then by RF front-end module, radiofrequency signal is down-converted to intermediate-freuqncy signal, and intermediate-freuqncy signal is demodulated into baseband signal, it is decoded processing to baseband signal by processing module again, and decoded baseband signal is sent to host computer, it is achieved thereby that to the monitoring of radiofrequency signal in RFID system.The radiofrequency signal audiomonitor volume that the present embodiment provides is little, cost is low, it is possible to meets RFID field research staff, on-the-spot application personnel and portable protocol is tested to the demand of equipment.
Accompanying drawing explanation
The structural representation of the radiofrequency signal audiomonitor embodiment one that Fig. 1 provides for this utility model；
Fig. 2 is the structural representation of antenna in Fig. 1；
The structural representation of the radiofrequency signal audiomonitor embodiment two that Fig. 3 provides for this utility model,
The structural representation of the radiofrequency signal audiomonitor embodiment three that Fig. 4 provides for this utility model.
Description of reference numerals:
10-antenna；20-RF front-end module；
30-processing module；
11-medium substrate；12-radiating element；
13-feeder line；14-earth plate；
15-match circuit；
The parallel microstrip line of 121-；The vertical microstrip line of 122-；
21-local oscillator；22-frequency mixer；
23-cymoscope；24-radio frequency band filter；
25-low-noise amplifier；26-intermediate-frequency filter；
27-baseband processing circuitry.
Detailed description of the invention
For making the purpose of this utility model embodiment, technical scheme and advantage clearly, below in conjunction with the accompanying drawing in this utility model embodiment, technical scheme in this utility model embodiment is clearly and completely described, obviously, described embodiment is a part of embodiment of this utility model, rather than whole embodiments.Based on the embodiment in this utility model, the every other embodiment that those of ordinary skill in the art obtain under not making creative work premise, broadly fall into the scope of this utility model protection.
The structural representation of the radiofrequency signal audiomonitor embodiment one that Fig. 1 provides for this utility model, as shown in Figure 1, the radiofrequency signal audiomonitor that the present embodiment provides includes: antenna 10, RF front-end module 20 and processing module 30, RF front-end module 20 is connected with antenna 10 and processing module 30 respectively；Wherein, antenna 10, it is used for obtaining radiofrequency signal；RF front-end module 20, for radiofrequency signal down-converts to intermediate-freuqncy signal, and is demodulated into baseband signal by intermediate-freuqncy signal；Processing module 30, for being decoded baseband signal processing, and is sent to host computer by decoded baseband signal.
Concrete, antenna 10 has the function of guided electromagnetic wave and radiated electromagnetic wave conversion, and the electromagnetic wave signal (i.e. radiofrequency signal) being responsible for catching in space sends RF front-end module 20 again to.The present embodiment uses the monopole antenna 10 being tuned to 845MHz to 950MHz, to reduce equipment volume.
RF front-end module 20 can be specifically the superhet of a single-conversion, is responsible for downconverting to radiofrequency signal intermediate frequency, and is demodulated into baseband signal further.
Processing module 30 can be specifically a micro-control unit (MicrocontrollerUnit, MCU) or other micro-chip processors, is responsible for carrying out baseband signal spacing (Bi-PhaseSpaceCoding, FM0) decoding process between two-phase；If the base band data comprised in decoded baseband signal meets the data form that RFID communication protocol specifies, then decoded baseband signal being sent to host computer, wherein, host computer is provided with man machine interface, it is possible to the baseband signal received is analyzed.In the present embodiment, processing module 30 preferably employs the MCU of STM32 series, to save power consumption and cost.It addition, processing module 30 can also provide power supply to RF front-end module 20；Processing module 30 can be provided with LAN (LocalAreaNetwork, LAN) interface, RS232 serial line interface etc., to realize being connected with host computer.
The radiofrequency signal audiomonitor that the present embodiment provides is concrete in use, is placed in by this equipment within rfid interrogator radiation scope, is connected with host computer by RS232 serial line interface or LAN interface etc..Antenna 10 then can continue to monitor the radio signal (i.e. radiofrequency signal) catching in uhf band and be then sent to RF front-end module 20；Radiofrequency signal down coversion that antenna 10 is caught by RF front-end module 20 is also demodulated into baseband signal, and send processing module 30 to；Baseband signal is decoded processing by processing module 30, if the base band data comprised in decoded baseband signal meets RFID communication protocol form, then decoded baseband signal is sent to upper computer software, it is achieved thereby that to the monitoring of radiofrequency signal in RFID system.In the present embodiment, the volume of antenna 10, RF front-end module 20 and processing module 30 is all smaller, cost is also relatively low, compare existing signal analyzer, the radiofrequency signal audiomonitor volume being made up of antenna 10, RF front-end module 20 and processing module 30 in the present embodiment is little, cost is low, it is possible to meets RFID field research staff, on-the-spot application personnel and portable protocol is tested to the demand of equipment.
The radiofrequency signal audiomonitor that the present embodiment provides, radiofrequency signal is obtained by antenna, then by RF front-end module, radiofrequency signal is down-converted to intermediate-freuqncy signal, and intermediate-freuqncy signal is demodulated into baseband signal, it is decoded processing to baseband signal by processing module again, and decoded baseband signal is sent to host computer, it is achieved thereby that to the monitoring of radiofrequency signal in RFID system.The radiofrequency signal audiomonitor volume that the present embodiment provides is little, cost is low, it is possible to meets RFID field research staff, on-the-spot application personnel and portable protocol is tested to the demand of equipment.
Fig. 2 is the structural representation of antenna in Fig. 1, as in figure 2 it is shown, in the present embodiment, antenna 10 specifically includes: medium substrate 11, radiating element 12, feeder line 13 and earth plate 14；Radiating element 12 and feeder line 13 are positioned at the upper surface of medium substrate 11, and earth plate 14 is positioned at the lower surface of medium substrate 11；Radiating element 12 includes multiple parallel microstrip line 121 and multiple vertical microstrip line 122, and parallel microstrip line 121 is arranged alternately formation S shape foldable structure with vertical microstrip line 122；Radiating element 12 end is electrically connected with feeder line 13 by vertical microstrip line 122, and the vertical microstrip line 122 of radiating element 12 end is positioned at the middle part of medium substrate 11.
Concrete, in the present embodiment, antenna 10 is the deformation micro-strip plane single pole sub antenna being tuned to 845MHz to 950MHz, and this antenna has the advantages that directivity is low, volume is little, is conducive to the miniaturization of equipment.In antenna 10, the size of each parts can be arranged according to actual needs, it is preferred that the thickness of medium substrate 11 is 0.8mm, and dielectric constant is 4.3；The length of radiating element 12 is 150mm, and width is 2mm；The width of feeder line 13 is 1mm, and the gap between feeder line 13 and earth plate 14 is 0.3mm.
In radiating element 12, parallel microstrip line 121 is arranged alternately formation S shape foldable structure with vertical microstrip line 122, to save space, reduces antenna volume；Parallel microstrip line 121 and the number of vertical microstrip line 122 that radiating element 12 specifically comprises can according to circumstances be arranged.In the present embodiment, it is preferred that parallel microstrip line 121 and vertical microstrip line 122 are 4, each parallel microstrip line 121 and the length that vertical microstrip line 122 overall length is radiating element 12, i.e. 150mm；Equal near the length of 3 parallel microstrip lines 121 of radiating element 12 head end；Length near the parallel microstrip line of the last item 121 of radiating element 12 end is in the half of the length of the parallel microstrip line 121 of Article 1 of radiating element 12 head end；The vertical microstrip line 122 one end microstrip line 121 parallel with the last item being positioned at radiating element 12 end connects, and the other end electrically connects with feeder line 13, and is positioned at the middle part of medium substrate 11.
It addition, match circuit 15 can be connected between radiating element 12 and feeder line 13, this match circuit 15 by resistance, inductively or capacitively form, to realize the impedance matching between radiating element 12 and feeder line 13.
The structural representation of the radiofrequency signal audiomonitor embodiment two that Fig. 3 provides for this utility model, the present embodiment is a kind of concrete circuit structure of RF front-end module 20 in above-mentioned embodiment illustrated in fig. 1.As it is shown on figure 3, RF front-end module 20 specifically includes: local oscillator 21, frequency mixer 22 and cymoscope 23, the input of frequency mixer 22 is connected with local oscillator 21 and antenna 10 respectively, and the outfan of frequency mixer 22 is connected with cymoscope 23；Local oscillator 21, is used for producing local oscillated signal；Frequency mixer 22, for being mixed radiofrequency signal and local oscillated signal, to produce intermediate-freuqncy signal；Cymoscope 23, for being demodulated into baseband signal by intermediate-freuqncy signal.
Concrete, local oscillator 21 is the core component of superhet, is used for producing local oscillated signal, it is possible to adopt the monolithic integrated optical circuit being integrated with phaselocked loop with voltage controlled oscillator.In the present embodiment, local oscillator 21 can pass through Serial Peripheral Interface (SPI) (SerialPeripheralInterface, SPI) it is connected with processing module 30, to be controlled the frequency of change local oscillated signal by processing module 30, ensure when different radio frequency signal frequency, keep IF signal frequency constant.
Frequency mixer 22 can adopt the structure such as double balanced mixer or single balance mixer, is responsible for mixing radiofrequency signal with local oscillator signal, obtains intermediate-freuqncy signal.In the present embodiment, it is preferred that frequency mixer 22 adopts double balanced mixer 22, to improve equipment performance.
Cymoscope 23 can adopt logarithmic detector or RMS rectifier etc..In the present embodiment, preferably, cymoscope adopts logarithmic detector, also referred to as logafier, it is made up of the amplifier of a series of cascades, and output signal is logarithmic function relation with input signal, it is ensured that when the changed power of input signal is very big, remain to detect desired signal accurately at outfan, namely can detect the input signal of Larger Dynamic scope.Amplitude shift keying ASK signal demodulating circuit it is used as, so that intermediate-freuqncy signal is demodulated into baseband signal at this.
The structural representation of the radiofrequency signal audiomonitor embodiment three that Fig. 4 provides for this utility model, the present embodiment is to the further optimization of RF front-end module 20 in above-mentioned embodiment illustrated in fig. 3.On the basis of above-mentioned embodiment illustrated in fig. 3, as shown in Figure 4, in the present embodiment, RF front-end module 20 also includes: radio frequency band filter 24 and low-noise amplifier 25, and antenna 10, radio frequency band filter 24, low-noise amplifier 25 and frequency mixer 22 are sequentially connected with；Radio frequency band filter 24, for being filtered radiofrequency signal；Low-noise amplifier 25, is used for amplifying filtered radiofrequency signal.
Concrete, radio frequency band filter 24 can adopt LTCC (LowTemperatureCo-firedCeramic, LTCC) wave filter, passband is at 845MHz to 950MHz, this wave filter has the advantages that Insertion Loss is little, volume is little, useful signal frequency out-of-band interference signal can be effectively filtered out, it is prevented that low-noise amplifier 25 is saturated.
Low-noise amplifier 25 specifically can adopt existing various noise amplifier, and it is responsible for amplifying radiofrequency signal.Low-noise amplifier 25 has extremely low noise coefficient and suitable gain amplifier, is to ensure that the critical component of whole receiver system signal to noise ratio.
Further, RF front-end module 20 can also include: intermediate-frequency filter 26 and baseband processing circuitry 27；Intermediate-frequency filter 26 is connected between local oscillator 21 and cymoscope 23, for intermediate-freuqncy signal is filtered；Baseband processing circuitry 27 is connected with cymoscope 23, for baseband signal being filtered and threshold judgement process.
Concrete, the SAW filter that intermediate-frequency filter 26 can adopt mid frequency to be 70MHz, this wave filter has that intermediate zone is precipitous, the great feature of stopband attenuation, and other garbage signals produced in the local frequency revealed after effectively filtering out mixing and mixing keep the pure of intermediate-freuqncy signal.
Baseband processing circuitry 27 is made up of a series of operation amplifier circuit, has the function such as baseband filtering, threshold judgement, it is possible to realize the filtering to baseband signal, and by analogue signal, baseband signal is converted to digital signal.
Optionally, in the present embodiment, RF front-end module 20 can be provided with intermediate-freuqncy signal interface and baseband signal interface；Intermediate-freuqncy signal interface is connected with intermediate-frequency filter 26, and baseband signal interface is connected with baseband processing circuitry 27.By the intermediate-freuqncy signal interface arranged on RF front-end module 20 and baseband signal interface, those skilled in the art can be convenient to use external instrument and test.
Last it is noted that various embodiments above is only in order to illustrate the technical solution of the utility model, it is not intended to limit；Although this utility model being described in detail with reference to foregoing embodiments, it will be understood by those within the art that: the technical scheme described in foregoing embodiments still can be modified by it, or wherein some or all of technical characteristic is carried out equivalent replacement；And these amendments or replacement, do not make the essence of appropriate technical solution depart from the scope of each embodiment technical scheme of this utility model.
Claims (8)
1. a radiofrequency signal audiomonitor, it is characterised in that including: antenna, RF front-end module and processing module, described RF front-end module is connected with described antenna and described processing module respectively；Wherein,
Described antenna, is used for obtaining radiofrequency signal；
Described RF front-end module, for described radiofrequency signal down-converts to intermediate-freuqncy signal, and is demodulated into baseband signal by described intermediate-freuqncy signal；
Described processing module, for being decoded described baseband signal processing, and is sent to host computer by decoded baseband signal.
2. radiofrequency signal audiomonitor according to claim 1, it is characterised in that described antenna specifically includes: medium substrate, radiating element, feeder line and earth plate；
Described radiating element and described feeder line are positioned at the upper surface of described medium substrate, and described earth plate is positioned at the lower surface of described medium substrate；
Described radiating element includes multiple parallel microstrip line and multiple vertical microstrip line, and described parallel microstrip line is arranged alternately formation S shape foldable structure with described vertical microstrip line；Described radiating element end is electrically connected with described feeder line by vertical microstrip line, and the vertical microstrip line of described radiating element end is positioned at the middle part of described medium substrate.
3. radiofrequency signal audiomonitor according to claim 1, it is characterized in that, described RF front-end module specifically includes: local oscillator, frequency mixer and cymoscope, the input of described frequency mixer is connected with described local oscillator and described antenna respectively, and the outfan of described frequency mixer is connected with described cymoscope；
Described local oscillator, is used for producing local oscillated signal；
Described frequency mixer, for being mixed described radiofrequency signal and described local oscillated signal, to produce intermediate-freuqncy signal；
Described cymoscope, for being demodulated into described baseband signal by described intermediate-freuqncy signal.
4. radiofrequency signal audiomonitor according to claim 3, it is characterized in that, described RF front-end module also includes: radio frequency band filter and low-noise amplifier, and described antenna, described radio frequency band filter, described low-noise amplifier and described frequency mixer are sequentially connected with；
Described radio frequency band filter, for being filtered described radiofrequency signal；
Described low-noise amplifier, is used for amplifying filtered radiofrequency signal.
5. radiofrequency signal audiomonitor according to claim 4, it is characterised in that described RF front-end module also includes: intermediate-frequency filter and baseband processing circuitry；
Described intermediate-frequency filter is connected between described local oscillator and described cymoscope, for described intermediate-freuqncy signal is filtered；
Described baseband processing circuitry is connected with described cymoscope, for described baseband signal being filtered and threshold judgement process.
6. radiofrequency signal audiomonitor according to claim 3, it is characterised in that described cymoscope is logarithmic detector.
7. radiofrequency signal audiomonitor according to claim 5, it is characterised in that be provided with intermediate-freuqncy signal interface and baseband signal interface on described RF front-end module；Described intermediate-freuqncy signal interface is connected with described intermediate-frequency filter, and described baseband signal interface is connected with described baseband processing circuitry.
8. radiofrequency signal audiomonitor according to claim 3, it is characterised in that described processing module is connected with described local oscillator, described processing module is additionally operable to control the frequency of the local oscillated signal that described local oscillator produces.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201521112642.7U CN205354044U (en) | 2015-12-28 | 2015-12-28 | Radiofrequency signal audiomonitor |
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| CN201521112642.7U CN205354044U (en) | 2015-12-28 | 2015-12-28 | Radiofrequency signal audiomonitor |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106919880A (en) * | 2015-12-28 | 2017-07-04 | 北京聚利科技股份有限公司 | Radiofrequency signal audiomonitor |
| CN107632217A (en) * | 2017-09-03 | 2018-01-26 | 电子科技大学 | A kind of device for detecting and tracking at a distance for electromagnetic interference source |
-
2015
- 2015-12-28 CN CN201521112642.7U patent/CN205354044U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106919880A (en) * | 2015-12-28 | 2017-07-04 | 北京聚利科技股份有限公司 | Radiofrequency signal audiomonitor |
| CN107632217A (en) * | 2017-09-03 | 2018-01-26 | 电子科技大学 | A kind of device for detecting and tracking at a distance for electromagnetic interference source |
| CN107632217B (en) * | 2017-09-03 | 2020-03-31 | 电子科技大学 | Device for electromagnetic interference source detection and remote tracking |
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Address after: 101300 room 015, building 8, No. 1, Linkong Second Road, Shunyi Park, Zhongguancun Science and Technology Park, Shunyi District, Beijing Patentee after: BEIJING JULI TECHNOLOGY Co.,Ltd. Address before: 102206, B, 504, Xinyuan Science Park, 97 Changping Road, Shahe Town, Beijing, Changping District Patentee before: BEIJING JULI SCIENCE & TECHNOLOGY Co.,Ltd. |
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