CN1457195A - Digital television transmitter - Google Patents
Digital television transmitter Download PDFInfo
- Publication number
- CN1457195A CN1457195A CN 03118127 CN03118127A CN1457195A CN 1457195 A CN1457195 A CN 1457195A CN 03118127 CN03118127 CN 03118127 CN 03118127 A CN03118127 A CN 03118127A CN 1457195 A CN1457195 A CN 1457195A
- Authority
- CN
- China
- Prior art keywords
- pilot
- power amplifier
- signal
- digital
- canceller
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000002347 injection Methods 0.000 claims abstract description 17
- 239000007924 injection Substances 0.000 claims abstract description 17
- 230000005540 biological transmission Effects 0.000 claims abstract description 9
- 230000002457 bidirectional effect Effects 0.000 claims description 11
- 238000010897 surface acoustic wave method Methods 0.000 claims description 11
- 238000001914 filtration Methods 0.000 claims description 6
- 235000006508 Nelumbo nucifera Nutrition 0.000 claims description 3
- 240000002853 Nelumbo nucifera Species 0.000 claims description 3
- 239000012530 fluid Substances 0.000 claims description 3
- 238000005516 engineering process Methods 0.000 abstract description 8
- 238000000034 method Methods 0.000 description 12
- 230000000694 effects Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 238000001228 spectrum Methods 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000010355 oscillation Effects 0.000 description 4
- 238000006386 neutralization reaction Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 230000003321 amplification Effects 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 230000010363 phase shift Effects 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 230000018199 S phase Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000010606 normalization Methods 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
Images
Landscapes
- Transmitters (AREA)
Abstract
A digital television transmitter comprises a local oscillator L0, a three-balanced mixer, a cavity filter, an amplifier, a one-way device, a pilot injection circuit, an automatic power control circuit ALC, a local oscillator, a singlechip, a-90-degree splitter, a first pilot generator, a first canceller and power amplifier circuit, a second pilot generator, a second canceller and power amplifier circuit, a two-way coupler and a second one-way device; the requirements of digital television technology transmission are met, and compared with the current analog television transmitter, the digital television transmitter has the advantages of high linearity, low phase noise, good in-band flatness and the like, and can be more suitable for normal operation under various condition environments.
Description
Technical field
The invention belongs to a kind of television transmission transmitter, particularly a kind of digital TV transmitter.
Technical background
Existing television transmitter designs in order to satisfy the analog television transmission technology requirement, and its key technical indexes is an amplitude-frequency characteristic.Continuous development along with China's radio and television services, digital television techniques has become the developing direction of radio, TV and film industries, but existing these television transmitters can not adapt to the demand of Digital Television in key technical index such as the linearity, phase noise and inband flatness.As shown in Figure 1, the leading indicator of simulated television transmitter mixer is converter noise, mixing gain, conversion loss and isolation etc.In general, frequency mixer has single balance, two balance, three balances etc.The technical indicator of single balance is the poorest, two balances secondly, and the technical indicator of three balances is best.In the simulated television transmitter, what generally adopt is single balance or double balanced mixer.
In the local oscillation circuit of simulated television transmitter, its voltage controlled oscillator VCO all is by triode, resistance, electric capacity, and discrete element such as inductance forms, the transmitter that also has even adopt the plug-in unit element to form VCO.We know, the key technical indexes of VCO is controlled bandwidth and phase noise, in the simulated television technology, do not have this most important index of test phase noise basically.Aspect filtering, simulating transmitting machine all is to adopt the little cavity body filter of minor spiral, and generally all is to use with a plurality of minor spiral filter series connection.So, to group delay, the time delay flatness all has very big influence in inband flatness and the 8MHz band.Caused the index of transmitter to descend poor work stability.
Amplifier in the simulated television transmitter, the gain of its amplification are 30dB.The main effect of amplifier is that the radio frequency level of output can be reached about 110dBv, thereby can promote the operate as normal of late-class circuit.The effect that promotes level and final power amplifier is that low power small-signal is become high-power signal, and can effectively launch.In the simulated television transmitter, this two-stage all is to adopt the AB class to amplify, even C class amplifying technique, these amplifying techniques, and its outstanding defective is exactly that poor linearity and phase noise are big, and third order intermodulation also can only reach-20 and arrive-35dBc.
By above narration as can be known, existing analogue technique transmitter can not adapt to current digital television techniques at all and promote demand, can not represent the development trend of digital television techniques.
Technology contents
The purpose of digital TV transmitter of the present invention is to go to develop for the requirement of digital television techniques, its omnibearing some critical technical problems such as the linearity in the digital television techniques, phase noise and inband flatness of having considered.
It comprises local oscillator LO, three balanced mixers, cavity body filter, amplifier, isolator, pilot tone injection circuit, automatic power control circuitry ALC, local oscillator, single-chip microcomputer ,-90 ° of splitters, first pilot generator, first Canceller and power amplifier, second pilot generator, second counteracting and power amplifier, bidirectional coupler and second isolator;
Digital intermediate frequency input IF is connected with three balanced mixers respectively with local oscillator LO, the fluid filter of connection chamber successively, amplifier, isolator and the pilot tone input circuit of this three balanced mixer; Automatic power control circuitry ALC is connected with amplifier; Digital medium-frequency signal IF inputs to three balanced mixers respectively from digital intermediate frequency input and local oscillator LO signal, digital radio signal after the three balanced mixer mixing amplifies through cavity body filter filtering, booster output, inputs to the pilot tone injection circuit after the restriction of isolator one-way transmission;
The control signal of described single-chip microcomputer inputs to first pilot generator, closes digital radio signal RFC that road generation contain pilot signal with digital radio signal by the pilot signal that this first pilot generator produces in the pilot tone injection circuit; This pilot tone injection circuit is connected with-90 ° of splitters; Described-90 ° of splitters are offset with first and power amplifier links to each other;
Described first counteracting and power amplifier comprise first phase shifter, first gain control circuit, the first category-A power amplifier, first Canceller of first delay line and series connection successively; And first output and the splitter between the single-chip microcomputer and first pilot receiver that are series at first Canceller; Wherein-90 ° splitter links to each other with first phase shifter with first delay line respectively; The control end of first phase shifter and first gain circuitry is connected with the control signal end of single-chip microcomputer respectively; The first input end of described first Canceller links to each other with the first category-A power amplifier, and second input links to each other with the other end of first delay line, and second output is connected with an end of second delay line of second counteracting and power amplifier; Device is associated with second pilot generator between first kind power amplifier and single-chip microcomputer;
Described second counteracting and power amplifier comprise that second supports customer, second delay line, second input of this second Canceller links to each other with second delay line, is in series with second phase shifter, second gain control circuit and the second category-A power amplifier between its first input end and the single-chip microcomputer successively; Second output of second Canceller links to each other with second isolator by bidirectional coupler; Wherein second phase shifter also links to each other with the splitter of first counteracting and power amplifier; The other end of second delay line of second counteracting and power amplifier is connected with second output of first Canceller;
The lotus root of described bidirectional coupler is closed and is in series with second pilot receiver between output and the single-chip microcomputer;
Be in series with first pilot generator between described single-chip microcomputer and the pilot tone injection circuit;
Described local oscillator LO is made of reference source, frequency synthesizer and low phase noise VCO.
Description of drawings
Fig. 1 is a simulated television transmitter principle block diagram;
Fig. 2 is a schematic block circuit diagram of the present invention;
Fig. 3 is the pilot generator theory diagram;
Fig. 4 is the pilot receiver theory diagram;
Fig. 5 is the Canceller theory diagram;
Fig. 6 is pilot signal spectrum figure;
Fig. 7 is the digital radio signal spectrogram;
Fig. 8 is the output spectrum figure of pilot tone injection circuit;
Fig. 9 is the first category-A power amplifier output spectrum figure;
Figure 10 is the spectrogram after first Canceller is offset;
Figure 11 second category-A power amplifier output spectrum figure;
Figure 12 is the second Canceller output spectrum figure.
Embodiment
Shown in Fig. 2-5, it comprises local oscillator LO, three balanced mixers, cavity body filter, amplifier, isolator, pilot tone injection circuit, automatic power control circuitry ALC, local oscillator, single-chip microcomputer ,-90 ° of splitters, first pilot generator, first Canceller and power amplifier, second pilot generator, second counteracting and power amplifier, bidirectional coupler and second isolator;
Digital intermediate frequency input IF is connected with three balanced mixers respectively with local oscillator LO, the fluid filter of connection chamber successively, amplifier, isolator and the pilot tone input circuit of this three balanced mixer; Automatic power control circuitry ALC is connected with amplifier; Digital medium-frequency signal IF inputs to three balanced mixers respectively from digital intermediate frequency input and local oscillator LO signal, digital radio signal after the three balanced mixer mixing amplifies through cavity body filter filtering, booster output, inputs to the pilot tone injection circuit after the restriction of isolator one-way transmission;
The control signal of described single-chip microcomputer inputs to first pilot generator, closes digital radio signal RFC that road generation contain pilot signal with digital radio signal by the pilot signal that this first pilot generator produces in the pilot tone injection circuit; This pilot tone injection circuit is connected with-90 ° of splitters; Described-90 ° of splitters are offset with first and power amplifier links to each other;
Described first counteracting and power amplifier comprise first phase shifter, first gain control circuit, the first category-A power amplifier, first Canceller of first delay line and series connection successively; And first output and the splitter between the single-chip microcomputer and first pilot receiver that are series at first Canceller; Wherein-90 ° splitter links to each other with first phase shifter with first delay line respectively; The control end of first phase shifter and first gain circuitry is connected with the control signal end of single-chip microcomputer respectively; The first input end of described first Canceller links to each other with the first category-A power amplifier, and second input links to each other with the other end of first delay line, and second output is connected with an end of second delay line of second counteracting and power amplifier; Device is associated with second pilot generator between first kind power amplifier and single-chip microcomputer;
Described second counteracting and power amplifier comprise that second supports customer, second delay line, second input of this second Canceller links to each other with second delay line, is in series with second phase shifter, second gain control circuit and the second category-A power amplifier between its first input end and the single-chip microcomputer successively; Second output of second Canceller links to each other with second isolator by bidirectional coupler; Wherein second phase shifter also links to each other with the splitter of first counteracting and power amplifier; The other end of second delay line of second counteracting and power amplifier is connected with second output of first Canceller;
The lotus root of described bidirectional coupler is closed and is in series with second pilot receiver between output and the single-chip microcomputer;
Be in series with first pilot generator between described single-chip microcomputer and the pilot tone injection circuit;
Described local oscillator LO is made of reference source, frequency synthesizer and low phase noise VCO.
Intermediate-freuqncy signal (the 35.25MHz that comes out by the digital QAM modulator, level is in 80-100dB μ scope) meet the digital intermediate frequency input IF (i.e. the IF of three balanced mixers end) of transmitter, because what frequency mixer adopted is three balanced mixers, so it is less demanding to the level power of intermediate-freuqncy signal, and RF end and IF end all present the goodish linearity, converter noise also low (about 3dB), input and output level height (about+10dBM), conversion loss little (about 6dB).Signal after the frequency conversion, the carrier-to-noise ratio height is more than 70dB.Specifically being converted to which channel, is to decide according to the frequency of local oscillator.Local oscillator LO is made up of VCO, frequency synthesizer and reference source.The VCO of this machine is the integrated SMD VCO that adopts the high output level of low phase noise.The phase difference level that VCO has an end compared by frequency synthesizer is controlled.Whole VCO and frequency synthesizer, reference source formed one closed circuit.Produce absolute standard (± 3KHZ), the local oscillation signal of low phase noise 125dBc/Hz@100kHz, this signal is access in the local oscillator input of three balanced mixers.In the radio-frequency head signal of three balanced mixers, more weak medium-frequency IF and local oscillator LO signal and image frequency etc. are arranged, medium-frequency IF and local oscillator LO signal must curb, the present invention has adopted four chamber cavity body filters of high rejection ratio, be characterized in time delay little (less than 10ns), high inhibition degree (greater than 70DB) and inband flatness little (± 0.1DB) etc.Guarantee the unblocked of useful digital radio signal, suppress the effect of unwanted signal.
The output of cavity body filter only leaves the digital RF signal that does not have damage basically, and this signal level (about 90DB μ v) is not enough to directly promote power amplifier, needs to be amplified to the output level that can promote power amplifier through the amplifier of gain about 30DB.The phase frequency and the amplitude-frequency characteristic of this amplifier are superior, have the broadband amplification effect, to guarantee the index of complete machine.Behind amplifier, (maximum 120dB μ v) can promote the superlinearity power amplifier to output level.And have one to be subjected to voltage-controlled automated power control ALC, this voltage is subjected to control by detecting superlinearity power amplifier output watt level, that is to say, the output level of amplifier is dynamic, when the power output of superlinearity power amplifier is big, ALC decay is big, otherwise it is little just to decay.In a word, be that the power output of superlinearity power amplifier is controlled on the fixed value automatically.Isolator guarantees the one-way transmission of digital radio signal; Pilot generator produces a pilot signal, and this signal is weak, and (7dBm), close among the signal RFC that comes out on the road with digital radio signal, pilot signal is used for analog digital RF signal.Digital RF signal phase amplitude etc. can both draw analysis in pilot signal.
The RFC signal through more stable-90 ° of splitters of phase place, becomes two-way with the RFC signal halves again.One the tunnel sends into the first category-A power amplifier after sending first phase shifter with phase shifting control function and first gain control circuit to.This first category-A power amplifier has the goodish linearity, and the power of output is about 30W.The pilot signal that second pilot generator produces has been injected in final stage input, and its level is about+13DBm.This pilot signal is to be used for representing harmonic signal that first power amplifier produces, and the phase amplitude of harmonic signal can be analyzed out in the pilot signal that second pilot signal generator produces.Another road RFC signal is offset with a part of signal of first category-A power amplifier output behind first delay line.If offset fully, after offsetting, only leave harmonic signal so.In this signal, the amplitude of the pilot signal of first pilot generator has illustrated the quality of current neutralization effect, and pilot signal is weak more, illustrates that neutralization effect is good more, otherwise just poor more; Another fraction of first and second category-A power amplifier output is respectively to the pilot reception end of first and second pilot receiver, single-chip microcomputer detects according to the pilot signal power that receives and sends control signal voltage to corresponding power amplifier, phase-shift circuit and gain control circuit, go to finish the control of power amplifier, phase shift and gain, make first and second Canceller reach best neutralization effect.
As Fig. 6-12, the signal that exports second isolator through bidirectional coupler to is the digital radio signal that does not comprise pilot signal.The output signal of second Canceller has divided the sub-fraction signal to detect as RF by bidirectional coupler, and most signals are exported through second isolator, and the signal of output can be penetrated after sending into power combiner.
Described first, second pilot generator comprises frequency synthesizer, voltage controlled oscillator, amplifier and SAW (Surface Acoustic Wave) filter; The serial clock of frequency synthesizer, corresponding with the single-chip microcomputer respectively port of latched port, serial data port, enable port and reference source port is connected, and voltage controlled oscillator links to each other with frequency synthesizer is two-way, and its output links to each other with SAW (Surface Acoustic Wave) filter through amplifier;
During start, send synchronizing signal to frequency synthesizer by serial clock, determine the number format of frequency synthesizer, serial data transmits frequency dividing ratio then, just determines the frequency of pilot tone.In the voltage controlled oscillator starting oscillation, the frequency feedback of generation is to synthesizer.Make comparisons with the reference source phase place behind Fractional-N frequency, error voltage is relatively controlled the voltage-controlled end of voltage controlled oscillator, and after voltage controlled oscillator was locked, the locking output of frequency synthesizer output high level was to single-chip microcomputer, and frequency synthesizer is locked.At this moment, Enable Pin output low level at once requires the frequency dividing ratio of frequency synthesizer to store, and pilot signal is exported through output.The output signal of voltage controlled oscillator is exported through arrowband SAW (Surface Acoustic Wave) filter filtering after amplifying again.
Described first, second pilot receiver comprises the surperficial narrow band filter of sound, and two balanced mixing circuit, low frequency amplify and the multiplication detecting circuit.
The digital radio signal that has pilot signal, behind surface acoustic wave narrow band filter narrow-band filtering, digital RF is suppressed, only surplus pilot signal, this signal and local oscillation signal mixing draw the intermediate-freuqncy signal IF of 100KHz, and the IF signal is drawn direct voltage by the detection of multiplication detecting circuit multiplication.This spread of voltage, it is with the pilot signal power among the RFC, and voltage and then changes, and voltage is arrived by the monolithic machine testing, and is corresponding, and single-chip microcomputer produces control signal.
As shown in Figure 5, described first, second Canceller is a four-terminal device, can be used as splitter or mixer and uses.When being used for mixer, radiofrequency signal is from pin 1 input, and pin 3 and pin 4 all have signal output, pin 2 no signal output in theory; When being used as bucking circuit,, amplitude opposite and the identical signal of frequency from pin 1 and pin 4 input phases, pin 2 and pin 3 outputs be result after the input signal of pin 1 and 4 two ports of pin is offset, one of them port must be by dummy load ground connection.
Technological merit of the present invention:
1, adopts three balanced mixing technology.
In the middle of digital TV transmitter, what at first its frequency mixer adopted is three balanced mixing skills Art, so at aspects such as converter noise and conversion loss, its performance indications just are not the simulation skills Art can be compared. More go up three balanced mixers, adopted advanced paster technique, so, Its high frequency characteristics is with respect to analogue technique, and is also better.
2, phase noise is very low.
We know that in the middle of TV tech, it is to be not more than that colourity and brightness and delay inequality require 100ns's, for the simulated television image, 100ns just is equivalent to move two mutually elements. Therefore, the impact to the simulated television image is very little. But, for our DTV Modulation signal, digital front-end system have adopted the modulation system of 64QAM, so when system's code check During for 10Mbit/s, its cycle has been exactly 100ns. In transmission system, had 100ns's Phase shift, when digital television signal is recovered, misjudgment and can't working. Thus can See, in the digital television system because of the not net terms of wireless transmission so that phase noise becomes one Individual very important technical indicator and need extraordinarily improvement. Clearly, for current those roots This is to satisfy that these are tight with regard to the simulated television emitter that does not need the test phase noise The condition of lattice. Voltage controlled oscillator VCO of the present invention has adopted standard packaging, and normalization is established The integrated VCO MIC of meter. Because the very high principle of integrated level, this VCO is used in the numeral electricity In technology, the key technologies such as the overall high frequency characteristics of emitter, phase noise are referred to Indicated very big raising, the stability of emitter is also better. In addition, we have adopted low frequency The reference source of rate drift, low phase noise, this also makes the performance upper of local oscillator and emitter Layer, thus round-the-clock normal operation under the various environment can be adapted to.
3, height draw up than cavity body filter, also be used in our digital TV transmitter.
Flat characteristic is better than the bulking property of simulated television emitter in the band of this cavity body filter Energy. And, in digital TV transmitter, only having used a cavity body filter, this is also Make the time delay of emitter exchange littler, relative simulating transmitting machine, it can reduce 10-20ns The time delay of level.
4, digital transmitter has adopted the superlinearity technology.
In the middle of the digital transmitter, its promotion level and final power amplifier all are to be operated in category-A to amplify shape,
Digital TV transmitter of the present invention has been considered the every key in the digital television techniques Technical problem, so with respect to for the television transmitter of front simulation, its linearity height, Phase noise hangs down and the performances such as inband flatness is good, also more can adapt under various conditions environmentals Normal operation. Add its full-automatic single chip microcomputer and process the stability of digital TV transmitter Also better, thus can not be subjected to the impact of the undesirable elements such as temperature, weather.
Claims (3)
1, a kind of digital TV transmitter, it is characterized in that: it comprises local oscillator LO, three balanced mixers, cavity body filter, amplifier, isolator, pilot tone injection circuit, automatic power control circuitry ALC, local oscillator, single-chip microcomputer ,-90 ° of splitters, first pilot generator, first Canceller and power amplifier, second pilot generator, second counteracting and power amplifier, bidirectional coupler and second isolator;
Digital intermediate frequency input IF is connected with three balanced mixers respectively with local oscillator LO, the fluid filter of connection chamber successively, amplifier, isolator and the pilot tone input circuit of this three balanced mixer; Automatic power control circuitry ALC is connected with amplifier; Digital medium-frequency signal IF inputs to three balanced mixers respectively from digital intermediate frequency input and local oscillator LO signal, digital radio signal after the three balanced mixer mixing amplifies through cavity body filter filtering, booster output, inputs to the pilot tone injection circuit after the restriction of isolator one-way transmission;
The control signal of described single-chip microcomputer inputs to first pilot generator, closes digital radio signal RFC that road generation contain pilot signal with digital radio signal by the pilot signal that this first pilot generator produces in the pilot tone injection circuit; This pilot tone injection circuit is connected with-90 ° of splitters; Described-90 ° of splitters are offset with first and power amplifier links to each other;
Described first counteracting and power amplifier comprise first phase shifter, first gain control circuit, the first category-A power amplifier, first Canceller of first delay line and series connection successively; And first output and the splitter between the single-chip microcomputer and first pilot receiver that are series at first Canceller; Wherein-90 ° splitter links to each other with first phase shifter with first delay line respectively; The control end of first phase shifter and first gain circuitry is connected with the control signal end of single-chip microcomputer respectively; The first input end of described first Canceller links to each other with the first category-A power amplifier, and second input links to each other with the other end of first delay line, and second output is connected with an end of second delay line of second counteracting and power amplifier; Device is associated with second pilot generator between first kind power amplifier and single-chip microcomputer;
Described second counteracting and power amplifier comprise that second supports customer, second delay line, second input of this second Canceller links to each other with second delay line, is in series with second phase shifter, second gain control circuit and the second category-A power amplifier between its first input end and the single-chip microcomputer successively; Second output of second Canceller links to each other with second isolator by bidirectional coupler; Wherein second phase shifter also links to each other with the splitter of first counteracting and power amplifier; The other end of second delay line of second counteracting and power amplifier is connected with second output of first Canceller;
The lotus root of described bidirectional coupler is closed and is in series with second pilot receiver between output and the single-chip microcomputer;
Be in series with first pilot generator between described single-chip microcomputer and the pilot tone injection circuit;
Described local oscillator LO is made of reference source, frequency synthesizer and low phase noise VCO;
2, a kind of digital TV transmitter as claimed in claim 1 is characterized in that described first, second pilot generator comprises frequency synthesizer, voltage controlled oscillator, amplifier and SAW (Surface Acoustic Wave) filter; The serial clock of frequency synthesizer, corresponding with the single-chip microcomputer respectively port of latched port, serial data port, enable port and reference source port is connected, and voltage controlled oscillator links to each other with frequency synthesizer is two-way, and its output links to each other with SAW (Surface Acoustic Wave) filter through amplifier.
3, a kind of digital TV transmitter as claimed in claim 1 is characterized in that described first, second pilot receiver comprises the surperficial narrow band filter of sound, and two balanced mixing circuit, low frequency amplify and the multiplication detecting circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03118127 CN1457195A (en) | 2003-02-28 | 2003-02-28 | Digital television transmitter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03118127 CN1457195A (en) | 2003-02-28 | 2003-02-28 | Digital television transmitter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1457195A true CN1457195A (en) | 2003-11-19 |
Family
ID=29411276
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 03118127 Pending CN1457195A (en) | 2003-02-28 | 2003-02-28 | Digital television transmitter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1457195A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100420284C (en) * | 2005-05-23 | 2008-09-17 | 浙江三维通信股份有限公司 | Power intensifier system for cofrequency transmitting of digital television |
| CN101010888B (en) * | 2004-08-30 | 2010-11-17 | 摩托罗拉公司 | Method and apparatus for dual mode power control |
| CN101529720B (en) * | 2006-04-21 | 2013-05-01 | 泰勒斯公司 | Device and method for amplification of radiocommunication signals |
| CN104242960A (en) * | 2014-08-13 | 2014-12-24 | 四川泰立科技有限公司 | High-power broadband emission device and method for 10GHz-12GHz white spectrum |
-
2003
- 2003-02-28 CN CN 03118127 patent/CN1457195A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101010888B (en) * | 2004-08-30 | 2010-11-17 | 摩托罗拉公司 | Method and apparatus for dual mode power control |
| CN100420284C (en) * | 2005-05-23 | 2008-09-17 | 浙江三维通信股份有限公司 | Power intensifier system for cofrequency transmitting of digital television |
| CN101529720B (en) * | 2006-04-21 | 2013-05-01 | 泰勒斯公司 | Device and method for amplification of radiocommunication signals |
| CN104242960A (en) * | 2014-08-13 | 2014-12-24 | 四川泰立科技有限公司 | High-power broadband emission device and method for 10GHz-12GHz white spectrum |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1722721B (en) | LO leakage and sideband image calibration system and method | |
| CN1282143A (en) | Power amplification circuit with load regulator for controlling adjacent and alternate channel power | |
| CN103916092B (en) | Hybrid digital/analog power amplifier | |
| Imai et al. | Novel linearizer using balanced circulators and its application to multilevel digital radio systems | |
| CN102215074B (en) | Power and standing-wave radio detection device and method | |
| CN1159083A (en) | Radio frequency power combiner | |
| CN101594327A (en) | Multichannel digital predistortion processing unit and pre-distortion method | |
| CN101378263A (en) | Multi-carrier digital receiver based on digital intermediate frequency and multi-carrier digital receive method | |
| US12068774B2 (en) | Transceiver with auxiliary receiver calibration apparatus and methodology | |
| CN107888273A (en) | A kind of link terminal radio-frequency channel | |
| CN110855247B (en) | E-band multi-channel receiver with vector modulator | |
| CN110011623A (en) | A kind of incorgruous power amplifier of dual band radio frequency | |
| CN109212484A (en) | phase shifter | |
| CN1217493C (en) | Wireless transceiver with subtractive filter compensating both transmit and receive artifacts | |
| CN1457195A (en) | Digital television transmitter | |
| CN2613112Y (en) | Digital television transmitter | |
| CN106603090A (en) | 12-channel transmitting-receiving frequency-conversion channel device | |
| CN1845464A (en) | Circuit for restraining LO leakage | |
| Zhang et al. | WCDMA PCS handset front end module | |
| CN201690414U (en) | Transceiving channel device for KA frequency converter | |
| Siligaris et al. | A 42.24 Gb/s Channel Bonding Up-Converter with integrated multi-LO generation in 45nm CMOS | |
| CN201509191U (en) | Transmitter for radio communication system | |
| CN114614844B (en) | Method and circuit for testing double-tone signal and radio frequency testing device | |
| JP3838952B2 (en) | Multi-carrier transmitter and control method thereof | |
| US8659354B2 (en) | Power-amplifier arrangement |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| ASS | Succession or assignment of patent right |
Owner name: XINGSHI DIGITAL NETWORKS EQUIPMENT CO., LTD., GUA Free format text: FORMER OWNER: XIANGDA SCIENCE + TECHNOLOGY CO., LTD., ZHUZHOU CITY Effective date: 20060512 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20060512 Address after: 513400, 603.604, Tian An technology innovation center, Yingbin Road, Guangzhou, Guangdong, Panyu District 730, China Applicant after: Guangzhou City Star Digital Network Equipment Co., Ltd. Address before: 412000, Zhuzhou, Hunan Province, 15 building, South Tower Applicant before: Xiangda Science & Technology Co., Ltd., Zhuzhou City |
|
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |