CN202395783U - Wideband optical fiber FM (frequency modulation) broadcasting amplifier and signal transmission system thereof - Google Patents
Wideband optical fiber FM (frequency modulation) broadcasting amplifier and signal transmission system thereof Download PDFInfo
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- CN202395783U CN202395783U CN2011205299609U CN201120529960U CN202395783U CN 202395783 U CN202395783 U CN 202395783U CN 2011205299609 U CN2011205299609 U CN 2011205299609U CN 201120529960 U CN201120529960 U CN 201120529960U CN 202395783 U CN202395783 U CN 202395783U
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Abstract
The utility model discloses a wideband optical fiber FM (frequency modulation) broadcasting amplifier, comprising a photoelectric conversion device, a first filter, a low-noise amplification module, a middle-frequency processing module, an amplification module and a second filter, all of which are sequentially connected through circuits, wherein the input of the photoelectric conversion device is an FM broadcasting optical signal, the FM broadcasting optical signal is converted to be a radio frequency signal through the photoelectric conversion device, the filters select required frequency bands, the low-noise amplification module is used for performing low-noise amplification to the radio frequency signal and transmitting the radio frequency signal to the middle-frequency processing module, the middle-frequency processing module changes the frequency of a signal to be middle frequency, performs middle-frequency filtering to filter a non-required signal, and then transmits the signal to the wideband amplification module after changing the frequency of the signal to an original frequency so as to output the signal after amplification and re-filtering. The utility model further discloses a signal transmission system of the wideband optical fiber FM broadcasting amplifier. According to the utility model, FM broadcasting signals of a plurality of frequency points can be synchronously transmitted and amplified and then the FM broadcasting signals are transmitted, thereby having the advantages of simple construction, low cost, good signal coverage rate and no interference on aviation radio.
Description
Technical field
The utility model relates to the technical field of wireless frequency modulation broadcasting, is the emission system of a kind of band optical fiber FM broadcasting amplifier and signal thereof specifically.
Background technology
Radio broadcasting promptly is FM broadcasting, and FM broadcasting is the equipment that a kind of mode with wireless transmit is transmitted broadcasting.Have the vertical rod of need not stringing, wide coverage, unlimited dilatation, convenient for installation and maintenance, reduced investment, the tonequality grace is characteristics clearly.Thoroughly solved traditional wired broadcasting difficult wiring, complicated, problems such as dilatancy is poor, damage metope have been installed.
The main mode that adopts the high-power covering in cell site of existing wireless frequency modulation broadcasting through building machine room and iron tower in higher geographical position, is installed transmitter, covers on a large scale through the antenna on the iron tower.Audio signal is modulated into the fm broadcast signal of single frequency point through frequency interleaved modulation modulator; Sending into optical sender changes into light signal and inserts optical cable; Be transferred to the machine room in higher geographical position such as mountain top through optical cable after; Convert the radio frequency fm broadcast signal to by optical receiver, the antenna by the iron tower top after transmitter amplifies emits.
The main mode that adopts the high-power covering in cell site of existing this wireless frequency modulation broadcasting, its major defect is:
1) technical sophistication, investment is big.The high-power coverage mode in cell site need be on the mountain top or other higher geographical position build machine room and iron tower, and solve problems such as corresponding power supply, lightning protection, ground connection.Therefore its technology is complicated, and the project construction cycle is long, and investment is big.
2) can only the single frequency point emission.The frequency-modulated broadcast transmitter of general employing several thousand of the high-power covering in cell site at present even last myriawatt power; It can only carry out amplifying emission to a frequency, and the program of launching a plurality of frequencies if desired simultaneously then will be prepared the transmitter of respective numbers and through multiplexer signal closed the road and send into antenna-feedback system again and launch.Therefore the cost increase is bigger when the program that will carry out a plurality of frequencies sends.
3) signal covers inhomogeneous.Because transmitter power is big, coverage distance is far away, so just causes the ground square signal near from the cell site very strong, the ground square signal of distance just very a little less than, simultaneously owing to receive the influence of barriers such as massif, be prone to form much signal blind zones among a small circle.
4) be prone to aviation radio is caused interference.Because on frequency partition, broadcast band and aviation frequency range are intersected each other to be had overlappingly mutually, and particularly FM broadcasting frequency range is close with aviation frequency range groundwork frequency range, and therefore, the aviation frequency range is easy to receive the influence of broadcast band inter-modulated signal.And geographical position of living in, FM broadcasting cell site itself is high, and transmitting power is disturbed normal aviation radio communication again up to several thousand even go up myriawatt so FM broadcasting takes place repeatedly.
The utility model content
The purpose of the utility model provides a kind ofly can be simultaneously to be transmitted and amplifies the fm broadcast signal of a plurality of frequencies, and cost is low, and signal covers, to the glitch-free band optical fiber FM broadcasting of aviation radio amplifier.
The utility model is realized through following technical proposals.
A kind of band optical fiber FM broadcasting amplifier is characterized in that: said band optical fiber FM broadcasting amplifier comprises light-electrical switching device, first filter, low noise amplification module, IF process module, power amplifier module and second filter of circuit connection in order, and wherein light-electrical switching device is used for converting light signal to radiofrequency signal; Said two filter is used for the noise signal filtering of not wanting, and said low noise amplification module is used for that signal is carried out low noise and amplifies, and said IF process module is used for fm broadcast signal is converted to intermediate frequency; Behind intermediate frequency filtering, be converted to primary frequency again; After the main effect of IF process module is to be converted to the intermediate frequency frequency range, utilize the intermediate-frequency filter of IF process module to carry out filtering, said power amplifier module is used for signal is carried out power amplification; Said light-electrical switching device be input as the light signal that contains FM broadcasting; Light signal converts radiofrequency signal into through light-electrical switching device, selects the frequency range that needs through filter, is undertaken after low noise amplifies by the low noise amplification module; Send into the IF process module; The IF process module to intermediate frequency, and is carried out intermediate frequency filtering, the filtering unwanted signal with signal frequency conversion; Send into the broadband power amplifier module after being converted to original frequency again, through amplifying also through exporting after the filtering once more.
Said low noise amplification module comprises low noise amplifying unit, ALC control unit, gain adjustment unit and the second level amplifying unit of circuit connection in order; The ALC control unit is provided with external control interface, and wherein the low noise amplifying unit is used to satisfy the amplification of FM broadcasting 87-108M full frequency band, and good inband flatness and low-noise factor is provided; Said ALC control unit is controlled by external control interface; When the power detection of power amplifier module and control unit detect power output when excessive, then can send control signal corresponding, be conveyed to the ALC control unit through external control interface; It is had an effect; Power output to keep power amplifier module is invariable, and said gain adjustment unit is used for gain-adjusted, is suitable scope to guarantee the complete machine gain; Said second level amplifying unit provides the bandwidth of broad and good inband flatness for the gain amplifying unit.
Said IF process module comprises the first mixing unit, first order amplifying unit, intermediate frequency filtering unit, second level amplifying unit and the second mixing unit and the first local oscillator unit and the second local oscillator unit; The first local oscillator unit is connected with the first mixing element circuit; The second local oscillator unit is connected with the second mixing element circuit; The first mixing unit is connected with first order amplifying unit circuit, and first order amplifying unit is connected with the intermediate frequency filtering element circuit, and the intermediate frequency filtering unit is connected with second level amplifying unit circuit; Second level amplifying unit is connected with the second mixing element circuit; Wherein the first mixing unit carries out mixing by local oscillation signal and the fm broadcast signal that the first local oscillator unit produces, and is the IF-FRE signal with the fm broadcast signal frequency conversion, and said first order amplifying unit amplifies intermediate-freuqncy signal; Remedy the gain loss that the intermediate frequency filtering unit brings; Said intermediate frequency filtering unit carries out thorough, clean Filtering Processing with intermediate-freuqncy signal, and said second level amplifying unit amplifies intermediate-freuqncy signal, remedies the gain loss that the intermediate frequency filtering unit brings; The said second mixing unit carries out mixing by local oscillation signal and intermediate-freuqncy signal that the second local oscillator unit produces, is the primary frequency signal with FM broadcasting intermediate-freuqncy signal frequency conversion again.
Said power amplifier module comprises promotion amplifying unit, power amplifier unit and power detection and control unit; Said promotion amplifying unit gains fm broadcast signal and power amplification; Said power amplifier unit is amplified to desired value with signal power; And finally send into antenna-feedback system and export; Said power detection and control unit:, send control signal corresponding according to the real output situation simultaneously, to reach the purpose of constant output through the mode of coupled power and through the computed in software output power value.
Said input optical signal>=-10dBm, optical wavelength is 1.55um or 1.31um, output standing-wave ratio≤1.5.
The utility model also provides a kind of emission system of launching aforementioned band optical fiber FM broadcasting amplifier signal; It is characterized in that: said emission system is made up of optical branching device or coupler, band optical fiber FM broadcasting amplifier and transmitting antenna; Optical branching device or coupler take out a part of light signal; Send into band optical fiber FM broadcasting amplifier, after handling by its completion light-electric conversion, intermediate frequency filtering, amplification etc., go out by transmission antennas transmit.
The utility model compared with prior art has the following advantages.
The utility model adopts the broadband power amplifier, can carry out amplifying emission to a plurality of frequencies simultaneously, need not build machine room and iron tower etc., because power is little, also can not cause interference to aviation radio.
The utility model band optical fiber FM broadcasting amplifier is to convert the FM broadcasting light signal to radiofrequency signal, and selects wherein useful frequency range, exports through filtering and after amplifying again.It is input as the FM broadcasting light signal, is output as the FM broadcasting radiofrequency signal.
More particularly, the utility model band optical fiber FM broadcasting amplifier possesses the Frequency Band Selection function, can utilize the frequency range that filter is selected from cable TV optical-fiber network or FM broadcasting optical-fiber network to be needed; Adopt the broadband power amplifier, can amplify the fm broadcast signal of a plurality of frequencies simultaneously, its information source can be the FM broadcasting optical-fiber network, also can be the cable TV optical-fiber network that is mixed with FM broadcasting.
The utility model band optical fiber FM broadcasting amplifier signal emission system can be built up the indoor or outdoors cell site; Outdoor cell site does not need machine room, adopts simple pole erection unit and antenna, all can set up website in the place that optical node is arranged; Environmental requirement is low to external world, uses flexibly.
In a word, the utlity model has following advantage:
1) construction period weak point, cost of investment is low.Band optical fiber FM broadcasting amplifier emission system need not built machine room and iron tower, all can build a station in the place that optical node is arranged, so its construction period is short, and cost of investment is low.
2) wideband transmit and amplification.The cable TV optical-fiber network that available FM broadcasting optical-fiber network perhaps is mixed with FM broadcasting is as information source.Can be simultaneously the fm broadcast signal of a plurality of frequencies be transmitted and amplifies and launch.
3) power is low, and signal covers evenly.Band optical fiber FM broadcasting amplifier emission system generally adopts the small-power emission, because booster output is low, the antenna setting height(from bottom) is also limited, so the signal covering evenly, and the blind area is less in the effective coverage range.
4) can not cause interference to other radio signal.As stated, because the FM broadcasting booster output is low, the antenna setting height(from bottom) is also limited, therefore can not cause interference such as aviation radio to other radio signal.
Description of drawings
Fig. 1 is the utility model band optical fiber FM broadcasting amplifier functional-block diagram;
Fig. 2 is the utility model band optical fiber FM broadcasting amplifier signal emission system functional-block diagram;
Fig. 3 is the low noise amplification module functional-block diagram of the utility model band optical fiber FM broadcasting amplifier;
Fig. 4 is a frequency processing module functional-block diagram among the utility model band optical fiber FM broadcasting amplifier;
Fig. 5 is the power amplifier module functional-block diagram of the utility model band optical fiber FM broadcasting amplifier.
Embodiment
Describe in further detail in the face of the utility model band optical fiber FM broadcasting amplifier down.
Like Fig. 1, the utility model band optical fiber FM broadcasting amplifier comprises light-electrical switching device, filter (i.e. first filter), low noise amplification module, IF process module, power amplifier module and filter (i.e. second filter) that circuit in order connects; Wherein light-electrical switching device is used for converting light signal to radiofrequency signal, and said two filters are used for the noise signal filtering of not wanting, and said low noise amplification module is used for that signal is carried out low noise and amplifies; Said IF process module is used for fm broadcast signal is converted to intermediate frequency, behind intermediate frequency filtering, is converted to primary frequency again, after the main effect of IF process module is to be converted to the intermediate frequency frequency range; Utilize the intermediate-frequency filter of IF process module to carry out thorough, clean filtering; Said power amplifier module is used for signal is carried out power amplification, said light-electrical switching device be input as the FM broadcasting light signal, the FM broadcasting light signal converts radiofrequency signal into through light-electrical switching device; Select the frequency range that needs through filter; Undertaken sending into the IF process module after low noise amplifies by the low noise amplification module, the IF process module with signal frequency conversion to intermediate frequency; And carry out intermediate frequency filtering; The filtering unwanted signal is sent into the broadband power amplifier module after being converted to original frequency again, through amplifying and through exporting after the filtering once more.Wherein input optical signal>=-10dBm, optical wavelength is 1.55um or 1.31um, output standing-wave ratio≤1.5.
Like Fig. 3, the low noise amplification module comprises low noise amplifying unit, ALC control unit, gain adjustment unit and the second level amplifying unit of circuit connection in order, and the ALC control unit is provided with external control interface; Wherein the low noise amplifying unit is used to satisfy the amplification of FM broadcasting 87-108M full frequency band; Good inband flatness and low-noise factor is provided, and said ALC control unit is controlled by external control interface, when the power detection of power amplifier module and control unit detect power output when excessive; Then can send control signal corresponding; Be conveyed to the ALC control unit through external control interface, it is had an effect, invariable with the power output that keeps power amplifier module; Said gain adjustment unit is used for gain-adjusted; To guarantee that the complete machine gain is suitable scope, said second level amplifying unit provides the bandwidth of broad and good inband flatness for the gain amplifying unit.
Comprise the first mixing unit, first order amplifying unit, intermediate frequency filtering unit, second level amplifying unit and the second mixing unit and the first local oscillator unit and the second local oscillator unit like Fig. 4 IF process module; The first local oscillator unit is connected with the first mixing element circuit; The second local oscillator unit is connected with the second mixing element circuit; The first mixing unit is connected with first order amplifying unit circuit, and first order amplifying unit is connected with the intermediate frequency filtering element circuit, and the intermediate frequency filtering unit is connected with second level amplifying unit circuit; Second level amplifying unit is connected with the second mixing element circuit; Wherein the first mixing unit carries out mixing by local oscillation signal and the fm broadcast signal that the first local oscillator unit produces, and is the IF-FRE signal with the fm broadcast signal frequency conversion, and said first order amplifying unit amplifies intermediate-freuqncy signal; Remedy the gain loss that the intermediate frequency filtering unit brings; Said intermediate frequency filtering unit carries out thorough, clean Filtering Processing with intermediate-freuqncy signal, and said second level amplifying unit amplifies intermediate-freuqncy signal, remedies the gain loss that the intermediate frequency filtering unit brings; The said second mixing unit carries out mixing by local oscillation signal and intermediate-freuqncy signal that the second local oscillator unit produces, is the primary frequency signal with FM broadcasting intermediate-freuqncy signal frequency conversion again.
Like Fig. 5; Power amplifier module comprises promotion amplifying unit, power amplifier unit and power detection and control unit; Said promotion amplifying unit gains fm broadcast signal and power amplification; Said power amplifier unit is amplified to desired value with signal power, and finally sends into antenna-feedback system output, said power detection and control unit: through the mode of coupled power and through the computed in software output power value; Simultaneously send control signal corresponding, to reach the purpose of constant output according to the real output situation.
Like Fig. 2; The utility model is launched the emission system of aforementioned band optical fiber FM broadcasting amplifier signal and is made up of optical branching device or coupler, band optical fiber FM broadcasting amplifier and transmitting antenna; Optical branching device or coupler take out a part of light signal; Send into band optical fiber FM broadcasting amplifier, after handling by its completion light-electric conversion, filtering, amplification etc., go out by transmission antennas transmit.The utility model band optical fiber FM broadcasting amplifier signal emission system can be built up the indoor or outdoors cell site; Outdoor cell site does not need machine room, adopts simple pole erection unit and antenna, all can set up website in the place that optical node is arranged; Environmental requirement is low to external world, uses flexibly.
Claims (6)
1. band optical fiber FM broadcasting amplifier; It is characterized in that: said band optical fiber FM broadcasting amplifier comprises light-electrical switching device, first filter, low noise amplification module, IF process module, power amplifier module and second filter of circuit connection in order
Wherein light-electrical switching device is used for converting light signal to radiofrequency signal; Said first, second filter is used for the noise signal filtering of not wanting; Said low noise amplification module is used for that signal is carried out low noise and amplifies, and said IF process module is used for fm broadcast signal is converted to intermediate frequency, behind intermediate frequency filtering, is converted to primary frequency again; After the main effect of IF process module is to be converted to the intermediate frequency frequency range; Utilize the intermediate-frequency filter of IF process module to carry out filtering more completely, said power amplifier module is used for signal is carried out power amplification
Said light-electrical switching device be input as the light signal that contains FM broadcasting, light signal converts radiofrequency signal into through light-electrical switching device, selects the frequency range that needs through filter; Undertaken sending into the IF process module after low noise amplifies by the low noise amplification module, the IF process module with signal frequency conversion to intermediate frequency; And carry out intermediate frequency filtering; The filtering unwanted signal is sent into the broadband power amplifier module after being converted to original frequency again, through amplifying and through exporting after the filtering once more.
2. band optical fiber FM broadcasting amplifier according to claim 1 is characterized in that: said low noise amplification module comprises low noise amplifying unit, ALC control unit, gain adjustment unit and the second level amplifying unit of circuit connection in order, and the ALC control unit is provided with external control interface; Wherein the low noise amplifying unit is used to satisfy the amplification of FM broadcasting 87-108M full frequency band; Good inband flatness and low-noise factor is provided, and said ALC control unit is controlled by external control interface, when the power detection of power amplifier module and control unit detect power output when excessive; Then can send control signal corresponding; Be conveyed to the ALC control unit through external control interface, it is had an effect, invariable with the power output that keeps power amplifier module; Said gain adjustment unit is used for gain-adjusted; To guarantee that the complete machine gain is suitable scope, said second level amplifying unit provides the bandwidth of broad and good inband flatness for the gain amplifying unit.
3. band optical fiber FM broadcasting amplifier according to claim 1; It is characterized in that: said IF process module comprises the first mixing unit, first order amplifying unit, intermediate frequency filtering unit, second level amplifying unit and the second mixing unit and the first local oscillator unit and the second local oscillator unit; The first local oscillator unit is connected with the first mixing element circuit, and the second local oscillator unit is connected with the second mixing element circuit, and the first mixing unit is connected with first order amplifying unit circuit; First order amplifying unit is connected with the intermediate frequency filtering element circuit; The intermediate frequency filtering unit is connected with second level amplifying unit circuit, and second level amplifying unit is connected with the second mixing element circuit, and wherein the first mixing unit carries out mixing by local oscillation signal and the fm broadcast signal that the first local oscillator unit produces; With the fm broadcast signal frequency conversion is the IF-FRE signal; Said first order amplifying unit amplifies intermediate-freuqncy signal, remedies the gain loss that the intermediate frequency filtering unit brings, and said intermediate frequency filtering unit carries out thorough, clean Filtering Processing with intermediate-freuqncy signal; Said second level amplifying unit amplifies intermediate-freuqncy signal; Remedy the gain loss that the intermediate frequency filtering unit brings, the said second mixing unit carries out mixing by local oscillation signal and intermediate-freuqncy signal that the second local oscillator unit produces, is the primary frequency signal with FM broadcasting intermediate-freuqncy signal frequency conversion again.
4. band optical fiber FM broadcasting amplifier according to claim 1; It is characterized in that: said power amplifier module comprises promotion amplifying unit, power amplifier unit and power detection and control unit; Said promotion amplifying unit gains fm broadcast signal and power amplification; Said power amplifier unit is amplified to desired value with signal power, and finally sends into antenna-feedback system output, said power detection and control unit: through the mode of coupled power and through the computed in software output power value; Simultaneously send control signal corresponding, to reach the purpose of constant output according to the real output situation.
5. band optical fiber FM broadcasting amplifier according to claim 1 is characterized in that: said input optical signal>=-10dBm, optical wavelength is 1.55um or 1.31um, output standing-wave ratio≤1.5.
6. emission system of launching the said band optical fiber FM broadcasting of the arbitrary claim of claim 1-5 amplifier signal; It is characterized in that: said emission system is made up of optical branching device or coupler, band optical fiber FM broadcasting amplifier and transmitting antenna; Optical branching device or coupler take out a part of light signal; Send into band optical fiber FM broadcasting amplifier, after handling by its completion light-electric conversion, intermediate frequency filtering, amplification etc., go out by transmission antennas transmit.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011205299609U CN202395783U (en) | 2011-12-16 | 2011-12-16 | Wideband optical fiber FM (frequency modulation) broadcasting amplifier and signal transmission system thereof |
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| CN2011205299609U CN202395783U (en) | 2011-12-16 | 2011-12-16 | Wideband optical fiber FM (frequency modulation) broadcasting amplifier and signal transmission system thereof |
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| CN202395783U true CN202395783U (en) | 2012-08-22 |
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| CN2011205299609U Expired - Lifetime CN202395783U (en) | 2011-12-16 | 2011-12-16 | Wideband optical fiber FM (frequency modulation) broadcasting amplifier and signal transmission system thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102571246A (en) * | 2011-12-16 | 2012-07-11 | 广州双友电子技术有限公司 | Broadband optical fiber frequency modulation broadcast amplifier and signal transmission system thereof |
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2011
- 2011-12-16 CN CN2011205299609U patent/CN202395783U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102571246A (en) * | 2011-12-16 | 2012-07-11 | 广州双友电子技术有限公司 | Broadband optical fiber frequency modulation broadcast amplifier and signal transmission system thereof |
| CN102571246B (en) * | 2011-12-16 | 2015-02-18 | 广州双友电子技术有限公司 | Broadband optical fiber frequency modulation broadcast amplifier and signal transmission system thereof |
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| CX01 | Expiry of patent term |
Granted publication date: 20120822 |
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| CX01 | Expiry of patent term |