CN207884609U - Radio circuit and radio frequency system - Google Patents
Radio circuit and radio frequency system Download PDFInfo
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- CN207884609U CN207884609U CN201820179087.7U CN201820179087U CN207884609U CN 207884609 U CN207884609 U CN 207884609U CN 201820179087 U CN201820179087 U CN 201820179087U CN 207884609 U CN207884609 U CN 207884609U
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- radio
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- gps
- circuit
- impedance matching
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Abstract
The utility model discloses radio circuit and radio frequency system.The circuit includes pcb board and the impedance matching circuit and radio frequency chip that are arranged on the pcb board, and one end of the impedance matching circuit is connect with the radio frequency chip；It further include the first shielding line, first shielding line has the characteristic impedance needed for transmitting radio frequency signal, one end of first shielding line connect to form the first tie point with the other end of the impedance matching circuit, and the other end of first shielding line draws the outside of the radio circuit for being connect with radio-frequency antenna.The radio frequency system includes the circuit.The utility model does not have to consider the problems of impedance matching, greatly simplifies the process of user's impedance matching, shortens the development cycle of product, to reduce cost.
Description
Technical field
The utility model is related to RF application, more particularly to a kind of radio circuit and the radio frequency system including the radio circuit
System.
Background technology
Radio frequency (RF, Radio Frequency) indicates can be radiated the electromagnetic frequency in space, radio frequency abbreviation RF radio frequencies,
Namely radio-frequency current, it is a kind of abbreviation of high-frequency ac variation electromagnetic wave.
Radio-frequency antenna receives radiofrequency signal, in order to obtain maximum signal power, it is necessary that load resistance is with signal
Source internal resistance is equal.Singal source resistance is equal in magnitude with the characteristic impedance of connect transmission line and phase is identical or the characteristic of transmission line
Impedance is identical as the equal in magnitude and phase of connect load impedance, be referred to as transmission line input terminal or output in impedance
Matching status, referred to as impedance matching.The intensity for receiving signal is directly affected whether the matching of impedance and receives stability.
Radio frequency has is widely applied field very much, for example, GPS real time clock circuits are calibrated using GPS signal, just makes
Use radio frequency.It makes or when relevant with the radio frequency module of use, needs the impedance matching for considering radio-frequency antenna, be that these modules are set
Count impedance matching circuit.The impedance matching of radio-frequency antenna is the problem of puzzled many Hardware Engineers, and impedance matching circuit is to electricity
The requirement of road plate is very high, causes cost also very high.Radio frequency have it is very strong professional, to Hardware Engineer profession require very
Height, and radio frequency testing instrument is expensive so that it makes or high using the cost with the relevant module of radio frequency.
GPS device generally all can be using active antenna, the signal wire of GPS active antennas while the again power cord as active antenna, such as
Fruit power supply, which handles the bad quality of reception for directly affecting GPS signal, leads to search that star is unstable, this also gives the impedance of radio-frequency antenna
With increasing difficulty.
In addition, for GPS real time clock circuits, GPS data needs the time when being written to RTC by MCU parsings, presses
According to 400K communication speed write-in the second, point, when, week, day, Month And Year, need the time of 20uS or so, wanted to clock system
It is also that can not be ignored to ask higher place, 20uS.
Utility model content
Purpose of the utility model is to solve the impedance matching for needing to consider the problems of radio-frequency antenna in the prior art,
It proposes a kind of radio circuit and includes the radio frequency system of the radio circuit.
In order to solve the above technical problems, the utility model uses following technical scheme：
Radio circuit, including pcb board and the impedance matching circuit and radio frequency chip that are arranged on the pcb board, it is described
One end of impedance matching circuit is connect with the radio frequency chip；Further include the first shielding line, first shielding line has transmission
One end of characteristic impedance needed for radiofrequency signal, first shielding line connect to be formed with the other end of the impedance matching circuit
The other end of first tie point, first shielding line draws the outside of the radio circuit for being connect with radio-frequency antenna.
In some preferred embodiments, further include antenna power and filter circuit, the antenna power is for being to penetrate
Frequency antenna is powered；The antenna power and the filter circuit are arranged on the pcb board, the antenna power and the filtering
One end of circuit connects, and the other end of the filter circuit is connect with first tie point.
In some preferred embodiments, the radio circuit is GPS real time clock circuits, and the radio frequency chip is
GPS chip；Further include the micro-control unit and clock chip being arranged on the pcb board, described in the micro-control unit connection
Clock chip and the GPS chip.
In further preferred embodiment, the GPS chip is also connect with the clock chip with to the clock
Chip sends 1PPS signals；The clock chip includes millisecond counter and second counter, and the millisecond counter is used for institute
It states second counter and sends second signal, the clock chip is used for the milli in the failing edge for the 1PPS signals for detecting GPS
Second counter O reset；The micro-control unit is used to extract GPS time information from GPS data and is detecting GPS's
When temporal information being written to the clock chip to realize school when the failing edge of 1PPS signals.
In some preferred embodiments, first shielding line is coaxial cable, and the coaxial cable is from the inside to the outside
Include center copper wire, insulator, reticulated conductive layer and wire outer skin successively.
In further preferred embodiment, the center copper wire is connect with the center of first tie point, described
Reticulated conductive layer is connected to ground.
In further preferred embodiment, the clock chip is provided with temperature-compensation circuit.
In further preferred embodiment, the clock chip can send the base for timing to the GPS chip
Quasi- pulse signal；The GPS chip can carry out timing according to the reference pulse signal.
Further include stand-by power supply in further preferred embodiment, the stand-by power supply is used to be the clock core
Piece is powered.
On the other hand, the utility model also provides a kind of radio frequency system, which includes any of the above-described radio circuit.
Compared with prior art, the beneficial effects of the utility model have：
Being drawn from the first tie point has the first shielding line and radio-frequency antenna of the characteristic impedance needed for transmitting radio frequency signal
Connection, the first shielding line and radio circuit are an entirety, in this way, directly by the first shielding line and radio-frequency antenna when use
Connection does not have to consider the problems of impedance matching, greatly simplifies the process of user's impedance matching, shortens the exploitation week of product
Phase, to reduce cost.
In a preferred embodiment, the utility model also has the advantages that：
Further, antenna power and filter circuit are arranged with other circuit units on pcb board, form an entirety,
The impedance matching of impedance matching circuit includes the impedance matching of antenna power and filter circuit and radio frequency chip, that is, considers
Influence of the power filter to radiofrequency signal, can enhance the stability of radio circuit, without considering further that antenna power and filtering
The impedance matching of circuit is further simplified the process of impedance matching.
Further, the 1PPS signals of GPS are whole second signals, failing edge indicate the end of current second, next second
Start, clock chip resets millisecond counter in the failing edge for the 1PPS signals for detecting GPS, and millisecond counter is opened again
Beginning timing, micro-control unit then also in the failing edge for the 1PPS signals for detecting GPS by when, the temporal informations such as minute, second are written
It,, can be with smart when high-ranking officers since the failing edge of 1PPS signals is up to nanosecond rank when thereby realizing school to clock chip
Degree accomplishes nanosecond rank, when to realize high-precision school.
Description of the drawings
Fig. 1 shows the circuit structure of the radio circuit of the utility model；
Fig. 2 shows the structures of the radio-frequency antenna of the utility model；
Fig. 3 shows a kind of circuit structure of variant of the radio circuit of the utility model；
Fig. 4 shows the internal structure of first shielding line of the utility model；
Fig. 5 shows the circuit structure of the GPS real time clock circuits of the utility model；
Fig. 6 shows the structure of the GPS antenna of the utility model；
Fig. 7 shows a kind of circuit structure of variant of the GPS real time clock circuits of the utility model；
Fig. 8 shows the circuit structure of another variant of the GPS real time clock circuits of the utility model；
Fig. 9 shows the internal structure of the clock chip of the utility model；
Figure 10 shows the circuit structure of the third variant of the GPS real time clock circuits of the utility model；
Figure 11 shows the circuit structure of the radio frequency system of the utility model.
Specific implementation mode
It elaborates below to the embodiment of the utility model.It is emphasized that following the description is only example
Property, rather than in order to limit the scope of the utility model and its application.
With reference to figure 1 and Fig. 2, radio circuit includes pcb board 1 and the impedance matching circuit being arranged on pcb board 1 11 and penetrates
One end of frequency chip 12, impedance matching circuit 11 is connect with radio frequency chip 12.Radio frequency chip 12 is for sending and receiving radio frequency letter
Number.Impedance matching circuit 11 is for the impedance matching between radio circuit and radio-frequency antenna 21.
Further include the first shielding line 17 with reference to figure 1 and Fig. 2, the first shielding line 17 has the spy needed for transmitting radio frequency signal
Property impedance, one end of the first shielding line 17 is connect with the other end of impedance matching circuit 11 to form the first tie point 101, the first screen
The other end for covering line 17 draws the outside of radio circuit for being connect with radio-frequency antenna 21.
With reference to figure 1 and Fig. 2, radio-frequency antenna 21 is passive antenna, and GPS real time clock circuits are penetrated by the reception of radio-frequency antenna 21
Frequency signal.Radio-frequency antenna 21 receives radiofrequency signal, and radiofrequency signal is transferred to radio frequency chip 12, radio frequency core through the first shielding line 17 again
Piece 12 handles radiofrequency signal.
As described above, being drawn from the first tie point 101 has first of the characteristic impedance needed for transmitting radio frequency signal
Shielding line 17 is connect with radio-frequency antenna 21, and the first shielding line 17 and radio circuit are an entirety, in this way, direct when use
First shielding line 17 is connect with radio-frequency antenna 21, centre eliminates the electricity by radio circuit to the impedance matching of radio-frequency antenna 21
The first shielding line 17 that road instead radio circuit carry, that is, without considering the problems of impedance matching, greatly
The process for simplifying user's impedance matching shortens the development cycle of product, to reduce cost.
Referring to figs. 2 and 3, when radio-frequency antenna 21 is active antenna, radio circuit further includes antenna power 15 and filtering
Circuit 16, antenna power 15 are used to power for radio-frequency antenna 21；Antenna power 15 and filter circuit 16 are arranged on pcb board 1, day
Line power supply 15 is connect with one end of filter circuit 16, and the other end of filter circuit 16 is connect with the first tie point 101.At this point, resistance
The impedance matching of anti-match circuit 11 includes the impedance matching of antenna power 15 and filter circuit 16 and radio frequency chip 12 and penetrates
The impedance matching of frequency chip 12 and radio-frequency antenna 21.
As described above, antenna power 15 and filter circuit 16 are arranged with other circuit units on pcb board, one is formed
A entirety, the impedance matching of impedance matching circuit 11 include the impedance of antenna power 15 and filter circuit 16 and radio frequency chip 12
Matching, that is, considers influence of the power filter to radiofrequency signal, can enhance the stability of radio circuit, without considering further that
The impedance matching of antenna power 15 and filter circuit 16 is further simplified the process of impedance matching.
The above content is described the utility model, but the utility model can also have some variants, such as：
First shielding line 17 is coaxial cable, which has 50 ohm characteristic impedances, for specially transmitting radio frequency
Signal can also select the coaxial cable of other characteristic impedances, such as 30 ohm characteristic impedances according to actual needs certainly.Ginseng
Fig. 4 is examined, the first shielding line 17 includes outside center copper wire 171, insulator 172, reticulated conductive layer 173 and electric wire successively from the inside to the outside
Skin 174.Preferably to shield interference, such as electrical Interference, center copper wire 171 is connect with the center of the first tie point 101, netted
Conductive layer 173 is connected to ground, for example, connect with the ground of antenna power 15 or with the power supplys of GPS real time clock circuits (in figure not
Show) ground connection.
Below by taking this radio circuit of GPS real time clock circuits as an example, the utility model is described in further detail.
With reference to figure 5, GPS real time clock circuits include pcb board 1 and the impedance matching circuit being arranged on pcb board 1 11,
GPS chip 12A, micro-control unit 13, clock chip 14, antenna power 15 and filter circuit 16, wherein GPS chip 12A are exactly
Radio frequency chip；Impedance matching circuit 11, GPS chip 12A, micro-control unit 13 and clock chip 14 are sequentially connected, antenna power
15 connect with one end of filter circuit 16, and the other end of filter circuit 16 is connect with impedance matching circuit 11 forms the first tie point
101.First tie point 101 is the pad on pcb board 1, the connection with pcb board 1.
With reference to figure 5 and Fig. 6, the impedance matching of impedance matching circuit 11 includes antenna power 15 and filter circuit 16 and GPS
The impedance matching of chip 12A, the impedance matching of GPS chip 12A and GPS antenna 21A, wherein GPS antenna 21A are exactly radio frequency day
Line.
Further include the first shielding line 17 with reference to figure 5, the first shielding line 17 has the characteristic resistance needed for transmitting radio frequency signal
Anti-, one end of the first shielding line 17 is connect with the first tie point 101, and the other end of the first shielding line 17 draws GPS real-time clocks
The outside of circuit with GPS antenna 21A for connecting.
With reference to figure 5 and Fig. 6, the operation principle of GPS real time clock circuits is such：GPS real time clock circuit uses have
Source antenna receives the radiofrequency signal from satellite, that is to say, that GPS antenna 21A is active antenna.The setting of filter circuit 16 exists
Between antenna power 15 and GPS antenna 21A, filter circuit 16 is used for the filtering of antenna power 15.Antenna power 15 is GPS antenna
21A powers, and GPS antenna 21A receives radiofrequency signal, and radiofrequency signal is transferred to GPS chip 12A, GPS core through the first shielding line 17 again
Piece 12A radiofrequency signal is handled after to micro-control unit 13 send include temporal information GPS data, micro-control unit
The GPS data that 13 couples of GPS chip 12A are sent is parsed to extract GPS time and geographical location information, and micro-control unit 13 is logical
Iic bus is crossed by temporal information write clock chip 14.
Certainly, if GPS antenna 21A is passive antenna, GPS real time clock circuits are without being arranged antenna power 15 and filter
Wave circuit 16.
As described above, when radio circuit is GPS real time clock circuits, it may have advantageous effect above-mentioned.
The above content is described the utility model, but the utility model can also have some variants, such as：
Clock chip 14 is provided with the clock chip of temperature-compensation circuit, by temperature-compensation circuit come compensation temperature pair
The influence of clock chip, to improve accuracy of timekeeping.
With reference to figure 7, stand-by power supply 18 can be also set, and stand-by power supply 18 is used to power for clock chip 14, to ensure GPS
Real time clock circuit continuously can reliably provide correct time information.
The utility model can also be achieved：
GPS chip 12A also connect with clock chip 14 with to clock chip 14 send 1PPS (pulse per second,
1PPS=1Hz=1 times/second) signal.With reference to figure 8, this connection can be connected by pin, for example set on GPS chip 12A
There is 1PPS to send pin 1201, being then equipped with 1PPS on clock chip 14 receives pin 1401, and 1PPS sends pin 1201 and 1PPS
Pin 1401 is received to connect；It can also be and wirelessly connect, such as bluetooth.
With reference to figure 9, clock chip 14 includes millisecond counter 141 and second counter 142.Certainly, for some clock cores
Piece also has minute counter, hour counter, day counter etc., and the utility model can be applicable in.Millisecond counter 141
Millisecond information is recorded, when reception 32768 (215) after pulse signal, millisecond counter 141 sends signal to second counter 142,
So that second counter 142 counts the second.
Clock chip 14 can reset millisecond counter 141 in the failing edge for the 1PPS signals for detecting GPS.
Micro-control unit 13 can be from extraction GPS time information in GPS data and in the case where detecting the 1PPS signals of GPS
Drop along when temporal information is written to clock chip 14 to realize school when.At this point, micro-control unit 13 by from GPS when, point,
It, certainly, can also be by temporal informations such as day, week, the moon, years according to actual conditions in second temporal information write clock chip 14
In write clock chip 14.Specifically, micro-control unit 13 is calibrated clock chip 14 by iic bus.
The 1PPS signals of GPS are whole second signals, and failing edge indicates the end of current second, beginning in next second, clock
Chip 14 resets millisecond counter 141 in the failing edge for the 1PPS signals for detecting GPS, and millisecond counter 141 is opened again
Beginning timing, micro-control unit 13 then also in the failing edge for the 1PPS signals for detecting GPS by when, the temporal informations such as minute, second write
Enter to clock chip 14, it, can be with high-ranking officers since the failing edge of 1PPS signals is up to nanosecond rank when thereby realizing school
Shi Jingdu accomplishes nanosecond rank, when to realize high-precision school.
Based on above explanation, the utility model also has other realization method：
With reference to figure 9, clock chip 14 is equipped with the crystal oscillator 143 for generating reference pulse signal, such as frequency
It is 32.768kHz without source crystal, the pulse signal of 32768Hz can be transmitted without source crystal for this, certainly, also may be used according to actual needs
With the other frequencies of use without source crystal.
Clock chip 14 can send the reference pulse signal for timing to GPS chip 12A.With reference to figure 10, the side of transmission
Formula can be sent by pin, for example clock chip 14 is equipped with reference signal and sends pin 1402, is then set on GPS chip 12A
There is reference signal to receive pin 1202, reference signal sends pin 1402 and connect with reference signal reception pin 1202, can also
Wirelessly send.
With reference to figure 10, GPS chip 12A is equipped with GPS timing units 121, and GPS timing units 121 are used for according to clock chip
14 reference pulse signals sent carry out timing.
It is such to be advantageous in that：Since GPS chip 12A itself is also required to timing, penetrated when GPS chip 12A can not be received
When frequency signal, that is, when can not receive the GPS signal of satellite, what GPS chip 12A can also be sent according to clock chip 14
Reference pulse signal carries out timing, it is ensured that GPS chip 12A under any circumstance can timing.Meanwhile GPS chip 12A is not necessarily to
External crystal oscillator, cost-saved and pcb board space.
The utility model also provides a kind of timing system, and with reference to figure 11, timing system includes above-mentioned radio circuit 100, penetrates
Frequency antenna 21 and the antenna socket 22 for connecting radio-frequency antenna 21 with radio circuit 100.
The above content is specific/preferred embodiment further detailed description of the utility model is combined, no
It can assert that the specific implementation of the utility model is confined to these explanations.For the common skill of the utility model technical field
For art personnel, without departing from the concept of the premise utility, the embodiment that these have been described can also be made
Some replacements or modification, and these are substituted or variant all shall be regarded as belonging to the scope of protection of the utility model.
Claims (10)
1. radio circuit, it is characterised in that：Including pcb board and the impedance matching circuit and radio frequency that are arranged on the pcb board
Chip, one end of the impedance matching circuit are connect with the radio frequency chip；Further include the first shielding line, first shielding line
With the characteristic impedance needed for transmitting radio frequency signal, the other end of one end and the impedance matching circuit of first shielding line
Connection forms the first tie point, and the outside that the other end of first shielding line draws the radio circuit is used for and radio-frequency antenna
Connection.
2. radio circuit according to claim 1, it is characterised in that：Further include antenna power and filter circuit, the day
Line power supply is used to power for radio-frequency antenna；The antenna power and the filter circuit are arranged on the pcb board, the antenna
Power supply is connect with one end of the filter circuit, and the other end of the filter circuit is connect with first tie point.
3. radio circuit according to claim 1 or 2, it is characterised in that：The radio circuit is GPS real-time clock electricity
Road, the radio frequency chip are GPS chip；Further include the micro-control unit and clock chip being arranged on the pcb board, it is described micro-
Control unit connects the clock chip and the GPS chip.
4. radio circuit according to claim 3, it is characterised in that：The GPS chip is also connect with the clock chip
To send 1PPS signals to the clock chip；The clock chip includes millisecond counter and second counter, the millisecond meter
Number device is used to send second signal to the second counter, and the clock chip is used for the decline in the 1PPS signals for detecting GPS
Along when the millisecond counter reset；The micro-control unit is used to extract GPS time information from GPS data and examine
When temporal information being written to the clock chip to realize school when the failing edge for measuring the 1PPS signals of GPS.
5. radio circuit according to claim 1, it is characterised in that：First shielding line is coaxial cable, described same
Shaft cable includes center copper wire, insulator, reticulated conductive layer and wire outer skin successively from the inside to the outside.
6. radio circuit according to claim 5, it is characterised in that：In the center copper wire and first tie point
The heart connects, and the reticulated conductive layer is connected to ground.
7. radio circuit according to claim 3, it is characterised in that：The clock chip is provided with temperature-compensation circuit.
8. radio circuit according to claim 3, it is characterised in that：The clock chip can be sent to the GPS chip
Reference pulse signal for timing；The GPS chip can carry out timing according to the reference pulse signal.
9. radio circuit according to claim 3, it is characterised in that：Further include stand-by power supply, the stand-by power supply is used for
It powers for the clock chip.
10. radio frequency system, including radio circuit as described in any one of claim 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820179087.7U CN207884609U (en) | 2018-02-01 | 2018-02-01 | Radio circuit and radio frequency system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820179087.7U CN207884609U (en) | 2018-02-01 | 2018-02-01 | Radio circuit and radio frequency system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207884609U true CN207884609U (en) | 2018-09-18 |
Family
ID=63510663
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201820179087.7U Active CN207884609U (en) | 2018-02-01 | 2018-02-01 | Radio circuit and radio frequency system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207884609U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108388107A (en) * | 2018-02-01 | 2018-08-10 | 深圳市兴威帆电子技术有限公司 | GPS real time clock circuits and timing system |
-
2018
- 2018-02-01 CN CN201820179087.7U patent/CN207884609U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108388107A (en) * | 2018-02-01 | 2018-08-10 | 深圳市兴威帆电子技术有限公司 | GPS real time clock circuits and timing system |
| CN108388107B (en) * | 2018-02-01 | 2023-11-21 | 深圳市兴威帆电子技术有限公司 | GPS real-time clock circuit and timing system |
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