CN204089824U - A kind of wide-band high sensitivity is without the light launch-box of spuious great dynamic range - Google Patents
A kind of wide-band high sensitivity is without the light launch-box of spuious great dynamic range Download PDFInfo
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- CN204089824U CN204089824U CN201420563660.6U CN201420563660U CN204089824U CN 204089824 U CN204089824 U CN 204089824U CN 201420563660 U CN201420563660 U CN 201420563660U CN 204089824 U CN204089824 U CN 204089824U
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Abstract
The utility model discloses the light launch-box of a kind of wide-band high sensitivity without spuious great dynamic range, it comprises RF selection switch, radio frequency pretreatment unit, bank of filters and optical modulator, the input of described RF selection switch is connected with radio-frequency input signals, the output of RF selection switch is connected with the input of radio frequency pretreatment unit, the output of radio frequency pretreatment unit is connected with the input of bank of filters, the output of bank of filters is connected with the input of optical modulator, RF selection switch from multi-channel rf signal behavior one tunnel as input, the radiofrequency signal of radio frequency pretreatment unit to input carries out preliminary treatment, the interference signal of bank of filters filtering radiofrequency signal after pretreatment, optical modulator converts rf signal to light signal, the light signal that optical modulator exports is connected with optical transmission medium.The utility model signal transmission attenuation is low, signal receiving sensitivity is high, signal transmission dynamic range large, and light modulation process medium frequency does not offset, do not produce interference signal.
Description
Technical field
The utility model relates to radio signal transmission field, particularly relates to the light launch-box of a kind of wide-band high sensitivity without spuious great dynamic range.
Background technology
Present radio communication technology all be unable to do without the transmission of radiofrequency signal, no matter broadcasting station, mobile communication base station, satellite communication base station etc.Usually, in order to reach better communication efficiency, the transmitting of communication base station or reception antenna are erected on higher steel tower, and communication station or receiving equipment are arranged on machine room, need to be connected by radio frequency cable with transmitting radio frequency signal between equipment and antenna.
(1) radio frequency cable loss is unfavorable for long-distance transmissions greatly
The signal frequency of transmit by RF cable is determined by system operating frequency scope, and the frequency range of general radio monitoring system is 1MHz ~ 3000MHz.Radio frequency cable is generally made up of center conductor, insulator, screen, oversheath etc.Radio frequency cable itself has certain insertion loss, and the higher loss of frequency is larger, and the longer loss of cable is larger, and the thinner loss of cable is larger.When transmitting radio frequency signal, the loss of cable can produce decay to signal, and the effect that impact receives.
So, require that when engineering design radio frequency cable loss is the smaller the better.When needing, the signal frequency of transmission is certain, wants the loss that radio frequency cable brings little, just needs to select thicker radio frequency cable.
(2) radio frequency cable is expensive
When needing, the signal frequency of transmission is certain, wants the loss that radio frequency cable brings little, just needs to select thicker radio frequency cable.But the cable of same model, the thicker price of cable is more expensive.Scout and radio guard for large-scale technique for fixing, need the eight secondary logarithm periodic antennas being erected at the high steel tower top of 100 meters, roof to draw to receive machine room, this needs eight cables more than 100 meter long, and its cost is quite expensive.
(3) radio frequency cable draw connect very inconvenient
In order to reduce the loss that radio frequency cable brings, the cable generally selected is not only thick but also hard.This brings inconvenience to erection again.Also scout and radio guard for large-scale technique for fixing, need eight 100 meters long not only thick but also hard cable leadings to receive machine room, this is quite difficult.
(4) radio frequency cable receives/draws and connects thunder and lightning and directly threaten calculator room equipment safety
Because the center conductor of radio frequency cable and screen all adopt metallic conductor.When experience thunderstorm hour, these conductors may receive and very strong thunder and lightning is introduced machine room and damage expensive equipment.
(5) radio frequency cable receives/draws and connects ELECTROMAGNETIC BOMB signal threat receiving equipment safety
Also because the center conductor of radio frequency cable and screen all adopt metallic conductor.When meeting with hostile electromagnetic bomb attacks, these conductors may receive and very strong ELECTROMAGNETIC BOMB energy is introduced machine room and damage expensive equipment.Transmit the transmitter and receiver of the signal of telecommunication and all equipment being connected to electric wire, the damage that the impact and causing that all will be subject to electromagnetic pulse cannot be repaired.
Utility model content
The purpose of this utility model is to overcome the deficiencies in the prior art, there is provided a kind of wide-band high sensitivity without the light launch-box of spuious great dynamic range, overcome the problem of signal attenuation of radiofrequency signal remote transmission, realize Signal transmissions by sending analog optical signal, and solve the Lightning Protection of radio signal transmission and the problem of poor anti jamming capability.
The purpose of this utility model is achieved through the following technical solutions: a kind of wide-band high sensitivity is without the light launch-box of spuious great dynamic range, it comprises RF selection switch, radio frequency pretreatment unit, bank of filters and optical modulator, the input of described RF selection switch is connected with radio-frequency input signals, the output of RF selection switch is connected with the input of radio frequency pretreatment unit, the output of radio frequency pretreatment unit is connected with the input of bank of filters, the output of bank of filters is connected with the input of optical modulator, RF selection switch from multi-channel rf signal behavior one tunnel as input, the radiofrequency signal of radio frequency pretreatment unit to input carries out preliminary treatment, the interference signal of bank of filters filtering radiofrequency signal after pretreatment, optical modulator converts rf signal to light signal, the light signal that optical modulator exports is connected with optical transmission medium.
Described RF selection switch is multiselect one variable connector, and its multiple not moved end is connected with the multiple radio-frequency input signals in outside, and its moved end and output are connected with follow-up radio frequency pretreatment unit.
Described radio frequency pretreatment unit comprises low noise amplifier, straight-through filter, input switch A and output switch A, input switch A and output switch A is multiselect one variable connector, the moved end of input switch and input are connected with the output of preceding radio frequency selector switch, the not moved end of input switch A is connected with the input of low noise amplifier and straight-through filter respectively, low noise amplifier is connected with the not moved end of output switch A respectively with the output of straight-through filter, and the moved end of output switch A and output are connected with follow-up bank of filters.
Described bank of filters comprises one or more filter, input switch B and output switch B, input switch B and output switch B is multiselect one variable connector, the moved end of input switch B and input are connected with the output of preceding radio frequency pretreatment unit, the not moved end of input switch B is connected with the input of one or more filter respectively, the output of one or more filter is connected with the not moved end of output switch B respectively, and the moved end of output switch and output are connected with follow-up optical modulator.
The quantity of described filter is decided by the quantity of radiofrequency signal input interface, and the quantity of filter is identical with the quantity of radiofrequency signal input interface.
It also comprises signal processing unit, logarithmic amplifier and optica l decode, the moved end of the constrained input switch B of described logarithmic amplifier and output connect, the output of logarithmic amplifier is connected with the input of signal processing unit signal, signal processing unit is also connected with the output of optica l decode, the light signal that optica l decode is responsible for being received by optical transmission medium converts rf signal to, and send rf signal to signal processing unit, the control of signal processing unit export respectively with RF selection switch, input switch A, output switch A, input switch B is connected with the control end of output switch B.
It also comprises power interface, and described power interface is powered for RF selection switch, radio frequency pretreatment unit, bank of filters, optical modulator, signal processing unit, logarithmic amplifier and optica l decode by being connected with DC power supply.
Described optical modulator is optical analog modulator, and optica l decode is light digital decoder, and optical modulator exports analog optical signal by optical transmission medium, and optical encoder receives digital optical signal by optical transmission medium.
Described optical transmission medium is optical fiber or optical cable etc.
The beneficial effects of the utility model are: a kind of wide-band of the utility model high sensitivity is without the light launch-box of spuious great dynamic range, intensity modulated is carried out by the signal of telecommunication of analog optical modulator to input, realize opto-electronic conversion, and effectively analog optical signal is sent into optical transmission medium; The utility model signal transmission attenuation is low, signal receiving sensitivity is high, signal transmission dynamic range is large, in light modulation process can not occurrence frequency shift phenomenon, other interference signal can not be produced.
Accompanying drawing explanation
Fig. 1 is the utility model schematic block circuit diagram;
Fig. 2 is the utility model optical modulator electro-optic conversion schematic diagram;
Fig. 3 is the utility model optical modulator electro-optic conversion schematic diagram.
Embodiment
Below in conjunction with accompanying drawing, the technical solution of the utility model is described in further detail, but protection range of the present utility model is not limited to the following stated.
As shown in Figure 1, a kind of wide-band high sensitivity is without the light launch-box of spuious great dynamic range, it comprises RF selection switch, radio frequency pretreatment unit, bank of filters and optical modulator, the input of described RF selection switch is connected with radio-frequency input signals, the output of RF selection switch is connected with the input of radio frequency pretreatment unit, the output of radio frequency pretreatment unit is connected with the input of bank of filters, the output of bank of filters is connected with the input of optical modulator, RF selection switch from multi-channel rf signal behavior one tunnel as input, the radiofrequency signal of radio frequency pretreatment unit to input carries out preliminary treatment, the interference signal of bank of filters filtering radiofrequency signal after pretreatment, optical modulator converts rf signal to light signal, the light signal that optical modulator exports is connected with optical transmission medium.
Described RF selection switch is multiselect one variable connector, and its multiple not moved end is connected with the multiple radio-frequency input signals in outside, and its moved end and output are connected with follow-up radio frequency pretreatment unit.
Described radio frequency pretreatment unit comprises low noise amplifier, straight-through filter, input switch A and output switch A, input switch A and output switch A is multiselect one variable connector, the moved end of input switch and input are connected with the output of preceding radio frequency selector switch, the not moved end of input switch A is connected with the input of low noise amplifier and straight-through filter respectively, low noise amplifier is connected with the not moved end of output switch A respectively with the output of straight-through filter, and the moved end of output switch A and output are connected with follow-up bank of filters.
Low noise amplifier radio frequency signal amplifies, and reduces system noise factor, increases signal receiving sensitivity.
Described bank of filters comprises one or more filter, input switch B and output switch B, input switch B and output switch B is multiselect one variable connector, the moved end of input switch B and input are connected with the output of preceding radio frequency pretreatment unit, the not moved end of input switch B is connected with the input of one or more filter respectively, the output of one or more filter is connected with the not moved end of output switch B respectively, and the moved end of output switch and output are connected with follow-up optical modulator.
The passband frequency range of each filter is different, for the interference signal outside Received signal strength band needed for filtering.The concrete bandwidth of each filter need design according to actual requirement.
The quantity of described filter is decided by the quantity of radiofrequency signal input interface, and the quantity of filter is identical with the quantity of radiofrequency signal input interface.
It also comprises signal processing unit, logarithmic amplifier and optica l decode, the moved end of the constrained input switch B of described logarithmic amplifier and output connect, the output of logarithmic amplifier is connected with the input of signal processing unit signal, signal processing unit is also connected with the output of optica l decode, the light signal that optica l decode is responsible for being received by optical transmission medium converts rf signal to, and send rf signal to signal processing unit, the control of signal processing unit export respectively with RF selection switch, input switch A, output switch A, input switch B is connected with the control end of output switch B.
Described signal processor is the signal processor of band AD sampling, can adopt MCU, DSP or FPGA.
It also comprises power interface, and described power interface is powered for RF selection switch, radio frequency pretreatment unit, bank of filters, optical modulator, signal processing unit, logarithmic amplifier and optica l decode by being connected with DC power supply.
Power interface can also be powered by being connected with AC power source adapter, solar panel or batteries.
It also has two optical fiber interfaces, and the first optical fiber interface is connected with optical modulator, and the second optical fiber interface is connected with optica l decode.
Described optical modulator is optical analog modulator, and optica l decode is light digital decoder, and optical modulator exports analog optical signal by optical transmission medium, and optical encoder receives digital optical signal by optical transmission medium.Digital electric signal both can be encoded to digital optical signal by this optica l decode, can be digital electric signal by the digital optical signal decoded back received again.
Realize mainly through two aspects without spuious light launch-box, be on the one hand rf signal without spuious, mainly filtered out the interference signal realization outside required Received signal strength band by the bandpass filtering of input filter group; On the other hand for light conversion is without spuious, mainly need to guarantee that the electric current (or voltage) of input electrical signal is operated in the linear working range of electrooptical device, avoid producing spurious signal because of the distortion of signal.
The light launch-box overcoming frequency shift (FS) realizes mainly through two aspects, is the frequency range consistency guaranteeing to transmit and receive light signal as much as possible on the one hand, avoids the distorted signals caused because transmitting-receiving frequency is inconsistent; On the other hand by calibrating the frequency of receiving and transmitting signal, eliminate because transmitting the frequency drift brought.
A kind of wide-band of the utility model high sensitivity is without the light launch-box of spuious great dynamic range, and its operation principle is as follows:
Step 1: the power interface of light launch-box and DC power supply or AC power source adapter or solar panel or batteries are connected, start powers on, the rf inputs of light launch-box exports with the radio frequency of antenna and is connected, the radio frequency signal received by reception antenna;
Step 2: the annexation that RF selection switch has occurred according to current moved end and not moved end, by this road radio-frequency terminals by this road radiofrequency signal access optical sender, and is sent to radio frequency pretreatment unit by this radiofrequency signal;
Step 3: the annexation that radio frequency pretreatment unit has occurred according to input switch A and output switch A, radio frequency signal carries out straight-through filtering or amplification, and pretreated radiofrequency signal is sent to bank of filters;
Step 4: the annexation that bank of filters has occurred according to input switch B and output switch B, carries out filtering to this radiofrequency signal, filtering interference signals by the filter on this road, and filtered radiofrequency signal is sent to optical modulator;
Step 5: optical modulator is converted to analog quantity light signal the radiofrequency signal received, and is exported by optical transmission medium;
Step 6: rf signal is after the bank of filters of light launch-box, also filtered rf signal is sent to logarithmic amplifier, filtered radiofrequency signal is carried out logarithmic amplification by logarithmic amplifier, and the radiofrequency signal after amplifying is sent to signal processing unit;
Step 7: after signal processing unit radio frequency signal carries out AD sampling, carry out signal power detection again, and judge according to the signal power size that detection obtains and control radio frequency pretreatment unit, control radio frequency pretreatment unit radio frequency signal carry out straight-through filtering or amplify process, detection information, signal gain and operating state are also sent to optica l decode by signal processing unit, result is converted to digital optical signal by optica l decode, and by optical transmission medium, this digital optical signal is outputted to host computer;
Step 8: the control figure light signal that optica l decode reception host computer is sent also is decoded, after decoding, this control signal is sent to signal processing unit, signal processing unit controls the moved end of RF selection switch according to the control signal of host computer, control the input switch A of radio frequency pretreatment unit and the moved end of output switch A, control the input switch B of bank of filters and the moved end of output switch B.
Smooth launch-box of the present utility model, its RF selection switch, for selecting the input channel of radiofrequency signal, can select the antenna radio-frequency signal inputting different frequency range.
Radio frequency pretreatment unit, for regulating the gain size of the radiofrequency signal of reception, improves the receiving sensitivity of signal.Meanwhile, also there is signal limiter defencive function, prevent the excessive signal of unexpected input and damage equipment.
Bank of filters and RF selection switch with the use of, for the out of band signal of the radiofrequency signal that filtering receives, reduce the interference of the radiofrequency signal received.
The rf signal of optical modulator to input carries out intensity modulated, realizes electro-optic conversion, and effectively light signal is sent into optical transmission medium.
Signal processor is the signal processor of band AD sampling, can adopt MCU, DSP or FPGA.Signal processor is used for signal demodulator, gain control, radio-frequency (RF) switch selects and filter is selected.
Logarithmic amplifier is used for RF signal power detection and measures.
The light signal that optica l decode is responsible for being received by optical transmission medium converts rf signal to, and sends rf signal to signal processing unit.
As shown in Figure 2, optical modulator carries out the electro-optic conversion of the signal of telecommunication to light signal, carries out intensity modulated to the rf signal of input, exports analog optical signal.Fig. 2 is optical modulator photoelectricity transformation principle figure, and optical modulator makes the power of carrier wave light wave change with the curent change of rf signal, thus carrys out transmission of information according to the power of light signal.
As shown in Figure 3, Fig. 3 is electro-optic conversion optical signal launch schematic diagram.
The utility model optical sender has multiple rf input interface, can input multi-channel rf signal.
Have a power interface, provide DC power supply to input, power interface can connect DC power supply, AC power source adapter, solar panel or batteries.
There are two optical fiber interfaces, an interface is for exporting modulated radio frequency light signal (i.e. analog quantity light signal), another interface inputs or outputs encoded digital optical signal, for sending the control signal of RF signal gain and work state information and reception host computer to host computer.
The function of the utility model light launch-box carries out intensity modulated by the signal of telecommunication of optical modulator to input, realizes opto-electronic conversion, and effectively light signal is sent into optical fiber.
Thunder energy be responded to/be transmitted to optical fiber containing any metallic conductor, can not.So, utilize Optical Fiber Transmission wide-band analog radio-frequency signal, namely reach the object of radio signal transmission, isolate again the harm that thunder and lightning brings.
Also because optical fiber is not containing any metallic conductor, can not respond to/transmit ELECTROMAGNETIC BOMB energy.So, utilize Optical Fiber Transmission wide-band analog radio-frequency signal, namely reach the object of radio signal transmission, isolate again the harm that ELECTROMAGNETIC BOMB brings.When being subject to ELECTROMAGNETIC BOMB and attacking, damage optical transmitter module at most.It is more cheap that this damages the equipment such as receiver than use radio frequency cable, more easily backs up and repair.
A kind of wide-band of the utility model high sensitivity, without the light launch-box of spuious great dynamic range, is carried out intensity modulated by the signal of telecommunication of analog optical modulator to input, is realized opto-electronic conversion, and effectively analog optical signal is sent into optical transmission medium; The utility model signal transmission attenuation is low, signal receiving sensitivity is high, signal transmission dynamic range is large, in light modulation process can not occurrence frequency shift phenomenon, other interference signal can not be produced.
Claims (8)
1. a wide-band high sensitivity is without the light launch-box of spuious great dynamic range, it is characterized in that: it comprises RF selection switch, radio frequency pretreatment unit, bank of filters and optical modulator, the input of described RF selection switch is connected with radio-frequency input signals, the output of RF selection switch is connected with the input of radio frequency pretreatment unit, the output of radio frequency pretreatment unit is connected with the input of bank of filters, the output of bank of filters is connected with the input of optical modulator, RF selection switch from multi-channel rf signal behavior one tunnel as input, the radiofrequency signal of radio frequency pretreatment unit to input carries out preliminary treatment, the interference signal of bank of filters filtering radiofrequency signal after pretreatment, optical modulator converts rf signal to light signal, the light signal that optical modulator exports is connected with optical transmission medium.
2. a kind of wide-band high sensitivity according to claim 1 is without the light launch-box of spuious great dynamic range, it is characterized in that: described RF selection switch is multiselect one variable connector, its multiple not moved end is connected with the multiple radio-frequency input signals in outside, and its moved end and output are connected with follow-up radio frequency pretreatment unit.
3. a kind of wide-band high sensitivity according to claim 1 is without the light launch-box of spuious great dynamic range, it is characterized in that: described radio frequency pretreatment unit comprises low noise amplifier, straight-through filter, input switch A and output switch A, input switch A and output switch A is multiselect one variable connector, the moved end of input switch and input are connected with the output of preceding radio frequency selector switch, the not moved end of input switch A is connected with the input of low noise amplifier and straight-through filter respectively, low noise amplifier is connected with the not moved end of output switch A respectively with the output of straight-through filter, the moved end of output switch A and output are connected with follow-up bank of filters.
4. a kind of wide-band high sensitivity according to claim 1 is without the light launch-box of spuious great dynamic range, it is characterized in that: described bank of filters comprises one or more filter, input switch B and output switch B, input switch B and output switch B is multiselect one variable connector, the moved end of input switch B and input are connected with the output of preceding radio frequency pretreatment unit, the not moved end of input switch B is connected with the input of one or more filter respectively, the output of one or more filter is connected with the not moved end of output switch B respectively, the moved end of output switch and output are connected with follow-up optical modulator.
5. a kind of wide-band high sensitivity according to claim 4 is without the light launch-box of spuious great dynamic range, it is characterized in that: the quantity of described filter is decided by the quantity of radiofrequency signal input interface, the quantity of filter is identical with the quantity of radiofrequency signal input interface.
6. a kind of wide-band high sensitivity according to claim 1 is without the light launch-box of spuious great dynamic range, it is characterized in that: it also comprises signal processing unit, logarithmic amplifier and optica l decode, the moved end of the constrained input switch B of described logarithmic amplifier and output connect, the output of logarithmic amplifier is connected with the input of signal processing unit signal, signal processing unit is also connected with the output of optica l decode, the light signal that optica l decode is responsible for being received by optical transmission medium converts rf signal to, and send rf signal to signal processing unit, the control of signal processing unit export respectively with RF selection switch, input switch A, output switch A, input switch B is connected with the control end of output switch B.
7. a kind of wide-band high sensitivity according to claim 1 is without the light launch-box of spuious great dynamic range, it is characterized in that: it also comprises power interface, described power interface is powered for RF selection switch, radio frequency pretreatment unit, bank of filters, optical modulator, signal processing unit, logarithmic amplifier and optica l decode by being connected with DC power supply.
8. a kind of wide-band high sensitivity according to claim 1 or 6 is without the light launch-box of spuious great dynamic range, it is characterized in that: described optical modulator is optical analog modulator, optica l decode is light digital decoder, optical modulator exports analog optical signal by optical transmission medium, and optical encoder receives digital optical signal by optical transmission medium.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420563660.6U CN204089824U (en) | 2014-09-28 | 2014-09-28 | A kind of wide-band high sensitivity is without the light launch-box of spuious great dynamic range |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201420563660.6U CN204089824U (en) | 2014-09-28 | 2014-09-28 | A kind of wide-band high sensitivity is without the light launch-box of spuious great dynamic range |
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| CN204089824U true CN204089824U (en) | 2015-01-07 |
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| CN201420563660.6U Active CN204089824U (en) | 2014-09-28 | 2014-09-28 | A kind of wide-band high sensitivity is without the light launch-box of spuious great dynamic range |
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