CN103227722A - DC modulation power supply OFDM communication system for unmanned aerial vehicle - Google Patents

Abstract

The invention relates to a DC (Direct Current) modulation power supply OFDM (Orthogonal Frequency Division Multiplexing) communication system for an unmanned aerial vehicle and belongs to the technical field of radio communication. The system comprises a transmitter and a receiver. The transmitter comprises an exciter, an amplitude forecasting judgment device, an encoder, a DC modulation power supply, a final power amplifier, an output filter and a transmitting antenna, wherein the amplitude forecasting judgment device is used for comparing an instantaneous amplitude value of a signal to be sent by the exciter and a set value and transmitting a comparison result to the encoder; the encoder is used for carrying out encoding on the comparison result to form a binary code; the DC modulation power supply is used for providing electric energy for the final power amplifier according to the binary code; the final power amplifier is used for carrying out power amplification on the signal to the sent by the exciter; the output filter is used for matching an output impedance of the final power amplifier with an input impedance of the transmitting antenna; and the transmitting antenna is used for converting an electric signal into a magnetic signal and transmitting the magnetic signal to a space. The DC modulation power supply OFDM communication system can improve power supply efficiency of the unmanned aerial vehicle.

Description

The direct current modulation power source ofdm communication system that is used for unmanned plane

Technical field

The present invention relates to a kind of direct current modulation power source ofdm communication system that is used for unmanned plane, relate in particular to the high direct current modulation power source ofdm communication system that is used for unmanned plane of a kind of power-efficient, belong to the radio communication technology field.

Background technology

Unmanned plane is a kind of not manned aircraft based on wireless remotecontrol or self program control.Compare with manned aircraft, it has, and volume is little, cost is low, easy to use, to making characteristics such as the station environmental requirement is low, battlefield survival is stronger.In the modern war, unmanned plane can go deep into one or two hundred kilometers of forward position, position and enemy's rear areas to be scouted enemy's situation and monitors, can be used as and deceive enemy's bait, the enemy is implemented to disturb, the enemy is attacked, can also communicate relaying, but, unmanned plane needs electric energy when finishing its task, if in a single day electric energy is used up, its serving as of task just can't be finished.

Fig. 1 provides the oscillogram of electric energy when being the final power amplifier amplifying signal that provides in the prior art.As shown in Figure 1, in order to make the u that transmits _FDistortionlessly transmit by wireless channel, the supply voltage value E that need provide at the final stage power-amplifier stage is greater than the maximum amplitude that is transmitted, and so, most of energy has been consumed by the form with heat energy.And to OFDM (Orthogonal Frequency Division Multiplexing OFDM) system, the peak-to-average ratio of signal is very high, the amplitude of most of signal is lower, and have only the amplitude of minimum a part of signal bigger, and adopt method of supplying power to of the prior art, add the power supply of fixing voltage or electric current to final stage power amplifier, the utilance of power supply is extremely low.

Summary of the invention

For overcoming the shortcoming that exists in the prior art, goal of the invention of the present invention provides a kind of direct current modulation power source ofdm communication system that is used for unmanned plane, and its power utilization rate height can reach more than 80%.

For realizing described goal of the invention, the invention provides a kind of direct current modulation power source ofdm communication system that is used for unmanned plane, it comprises transmitter and receiver, described transmitter comprises: exciter, amplitude prediction decision device, encoder, the direct current modulation power source, the final power amplifier that the signal that is used for will sending exciter carries out power amplification, be used for the output filter that the input impedance of the output impedance of final power amplifier and transmitting antenna is mated and be used for that the signal of telecommunication through the final stage power amplification become magnetic signal and be transmitted into the transmitting antenna in space, described receiver comprises: the reception antenna that is used for the space magnetic signal is become the signal of telecommunication, the small signal amplifier that the signal of telecommunication that is used for that reception antenna is received amplifies, be used for the local oscillation signal that small signal amplifier institute's amplifying signal and first oscillator at the corresponding levels are produced is carried out first frequency mixer that down-conversion forms intermediate-freuqncy signal, be used for intermediate-freuqncy signal is carried out the A-D converter that analog to digital conversion forms data-signal, be used for removing the time interval of data-signal, then carry out serial to parallel conversion successively, the symbol inverse mapping device that the ofdm demodulator of FFT conversion and parallel serial conversion and the signal that is used for that ofdm demodulator is exported carry out the symbol inverse mapping, it is characterized in that, amplitude prediction decision device compares the instantaneous amplitude and the set point of the signal that exciter will send, and sends comparative result to encoder; The encoder compared result formation binary code of encoding, the direct current modulation power source provides electric energy according to binary code to final power amplifier; Described direct current modulation power source comprises n level direct voltage unit, each direct voltage unit is by the cascade of afterflow coil, each direct voltage unit comprises a battery pack, a fly-wheel diode, an electronic switch and a driving stage, and the positive pole of battery pack is connected to the negative pole of fly-wheel diode; The positive pole of fly-wheel diode is connected to first end of electronic switch, second end of electronic switch is connected to the negative pole of battery pack, the control end of electronic switch is connected to driving stage, driving stage is according to the break-make of the binary code control electronic switch that encoder provided, and described n is greater than or equal to 2 integer.

Preferably, exciter comprises symbol mapper, the OFDM modulator, the D/A translation circuit, second frequency mixer, second oscillator at the corresponding levels and the prime amplifier, wherein, the serial binary code stream that symbol mapper is used for being imported divides into groups to form data symbol and data symbol is mapped to the complex data data sequence, the OFDM modulator is used for institute's complex data data sequence serial to parallel conversion and is modulated to N subcarrier, then carry out the IFFT conversion and form parallel time domain data, i.e. Bing Hang OFDM symbol, described parallel time domain data is carried out the OFDM symbol that parallel serial conversion forms serial, then the OFDM of each serial intersymbol insert guard time form at interval serial insertion guard time OFDM symbol data streams at interval; The D/A translation circuit carries out digital-to-analogue conversion with data flow and forms analog signal u _iSecond frequency mixer is used for analog signal u _iLocal oscillation signal u with the second oscillator generation at the corresponding levels ₀Carry out up-conversion and form signal u to be sent _h, prime amplifier is to sent signal u _hAmplify and give final power amplifier and carry out power amplification.

Compared with prior art, the direct current modulation power source ofdm communication system that is used for unmanned plane provided by the invention can bring up to 60% with the power utilization rate.

Description of drawings

Fig. 1 provides the oscillogram of electric energy when being the final power amplifier amplifying signal that provides in the prior art;

Fig. 2 is the composition frame chart that is used for the direct current modulation power source ofdm communication system of unmanned plane provided by the invention;

Fig. 3 is the composition frame chart of direct current modulation power source provided by the invention.

Fig. 4 provides the oscillogram of electric energy when being final power amplifier amplifying signal provided by the invention.

Embodiment

Below in conjunction with accompanying drawing, describe the present invention in detail.

Fig. 2 is the composition frame chart that is used for the direct current modulation power source ofdm communication system of unmanned plane provided by the invention.As shown in Figure 2, the invention provides a kind of direct current modulation power source ofdm communication system that is used for unmanned plane, it comprises transmitter and receiver, described transmitter comprises: exciter, amplitude prediction decision device, encoder, the direct current modulation power source, the final power amplifier that the signal that is used for will sending exciter carries out power amplification, be used for the output filter that the input impedance of the output impedance of final power amplifier and transmitting antenna is mated and be used for that the signal of telecommunication through the final stage power amplification become magnetic signal and be transmitted into the transmitting antenna in space, described receiver comprises: the reception antenna that is used for the space magnetic signal is become the signal of telecommunication, the small signal amplifier that the signal of telecommunication that is used for that reception antenna is received amplifies, be used for the local oscillation signal that small signal amplifier institute's amplifying signal and first oscillator at the corresponding levels are produced is carried out first frequency mixer that down-conversion forms intermediate-freuqncy signal, be used for intermediate-freuqncy signal is carried out the A-D converter that analog to digital conversion forms data-signal, be used for removing the time interval of data-signal, then carry out serial to parallel conversion successively, the symbol inverse mapping device that the ofdm demodulator of FFT conversion and parallel serial conversion and the signal that is used for that ofdm demodulator is exported carry out the symbol inverse mapping.Exciter comprises symbol mapper, OFDM modulator, D/A translation circuit, frequency mixer, oscillator at the corresponding levels and prime amplifier, wherein, the serial binary code stream that symbol mapper is used for being imported divides into groups to form data symbol and data symbol is mapped to the complex data sequence, the OFDM modulator is used for the complex data sequence being carried out serial to parallel conversion and being modulated to K subcarrier, and the data on K subcarrier are designated as X ₀, X ₀..., X _K-1Then carry out the IFFT conversion and form parallel time domain data x ₀, x ₁..., x _K-1, i.e. x ₀, x ₁..., x _K-1Be an OFDM symbol, described parallel time domain data is carried out the OFDM symbol that parallel serial conversion forms serial, then insert guard time and form the OFDM code element at interval at each OFDM intersymbol; The D/A translation circuit carries out digital-to-analogue conversion with data flow and forms analog signal u _iSecond frequency mixer is used for analog signal u _iLocal oscillation signal u with the second oscillator generation at the corresponding levels ₀Carry out up-conversion and form signal u to be sent _h, prime amplifier is to sent signal u _hAmplify and give final power amplifier and carry out power amplification.Amplitude prediction decision device is to x ₀, x ₀..., x _K-1Amplitude successively with n set point A _T1, set point A _T1..., set point A _Tn(wherein, A _T1＜A _T1＜...,＜A _Tn) compare, and sending comparative result to encoder, encoder is according to the comparative result formation binary code of encoding, and the direct current modulation power source provides electric energy according to binary code to final stage power amplifier.Undistorted for guaranteeing signal, usually, set point A _TnMaximum greater than data in all OFDM symbols.

Still as shown in Figure 2, the binary code stream of importing at transmitting terminal divides into groups to form data symbol, and data symbol forms the complex data sequence through the symbol mapper mapping, forms the parallel low rate data streams X of K bar behind the complex data sequence serial to parallel conversion ₀, X ₀..., X _K-1It is carried out the sample value that the IFFT conversion obtains time domain:

$x_k=\underset{m=0}{\overset{K=1}{\mathrm{\&Sigma;}}}{X}_{\mathrm{<figure-callout\; id="2"\; label="m\; e\; i"\; filenames="HSA00000866160800021.png"\; state="\{\{state\}\}">m</figure-callout>}}{e}^i{2\mathrm{\&pi;nk}/K}^{}$

Wherein, m is the discrete point of frequency domain, and k is the discrete point of time domain.

At receiving terminal, removing guard time signal at interval is y through the time domain data that serial to parallel conversion forms ₀, y ₁..., y _K-1, it is carried out the value that the FFT conversion obtains frequency domain:

$Y_m=\underset{k=0}{\overset{K=1}{\mathrm{\&Sigma;}}}{y}_k{e}^{-\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="HSA00000866160800021.png"\; state="\{\{state\}\}">i</figure-callout>}2\mathrm{\&pi;nk}/K}.$

But Fig. 3 is the composition frame chart of direct current modulation power source provided by the invention.As shown in Figure 3, described direct current modulation power source comprises n optical transmitting set OT ₀, OT ₁, OT ₂And OT _N, N=n-1, n optical receiver OR ₀, OR ₁, OR ₂And OR _NWith n level direct current unit, each direct voltage unit is by the cascade of afterflow coil, and described n is greater than or equal to 2 integer.Described optical transmitting set converts the binary control signal of encoder output to light signal to arrive corresponding optical receiver by Optical Fiber Transmission.Described optical receiver receives the light signal that corresponding optical transmitting set emission comes, and the signal of telecommunication that the light signal that receives is converted to the controlling and driving level realizes being in the high voltage isolation of direct voltages at different levels unit and low level control section on the suspension voltage with this.

First direct voltage unit M ₀Comprise a battery pack U ₀, a sustained diode ₀, an electronic switch and a driving stage P ₀, electronic switch is CMOS pipe CMOS ₀, described battery pack U ₀Positive pole be connected in sustained diode ₀Negative pole; Sustained diode ₀Positive pole be connected to CMOS pipe CMOS ₀Drain electrode, CMOS manages CMOS ₀Source electrode be connected to described battery pack U ₀Negative pole, CMOS manages CMOS ₀Grid be connected to driving stage P ₀, driving stage P ₀According to optical receiver OR ₀The binary system control command that encoder the sent control CMOS pipe CMOS that is received ₀Break-make.CMOS manages CMOS ₀Work on off state, as CMOS pipe CMOS ₀High potential of grid input the time, CMOS manages CMOS ₀Conducting, battery pack U ₀Negative pole be equivalent to receive sustained diode ₀Positive pole.Sustained diode ₀The voltage at two ends is U ₀, the upper end is for just, and the lower end is for negative.As CMOS pipe CMOS ₀Electronegative potential of grid input the time, CMOS manages CMOS ₀End.Sustained diode ₀The voltage at two ends is diode junction voltage.

In like manner, second direct voltage unit M ₁Comprise a battery pack U ₁, a rectifier R ₁, a sustained diode ₁, an electronic switch and a driving stage P ₁, electronic switch is CMOS pipe CMOS ₁, described battery pack U ₁Positive pole be connected in and be connected to sustained diode ₁Negative pole; Sustained diode ₁Positive pole be connected to CMOS pipe CMOS ₁Drain electrode, CMOS manages CMOS ₁Source electrode battery pack U ₁Negative pole, CMOS manages CMOS ₁Grid be connected to driving stage P ₁, by driving stage P ₁According to optical receiver OR ₁The binary system control command that encoder the sent control CMOS pipe CMOS that is received ₁Break-make.CMOS manages CMOS ₁Work on off state, as CMOS pipe CMOS ₁High potential of grid input the time, CMOS manages CMOS ₁Conducting, battery pack U ₁Negative pole be equivalent to receive sustained diode ₁Positive pole.Sustained diode ₁The voltage at two ends is U ₁, the upper end is for just, and the lower end is for negative.As CMOS pipe CMOS ₁Electronegative potential of grid input the time, CMOS manages CMOS ₁End.Sustained diode ₁The voltage at two ends is diode junction voltage.

The 3rd direct voltage unit M ₂Comprise a battery pack U ₂, a rectifier R ₂, a sustained diode ₂, an electronic switch and a driving stage P ₂, electronic switch is CMOS pipe CMOS ₂, described battery pack U ₂, positive pole be connected to the negative pole of fly-wheel diode; Sustained diode ₂Positive pole be connected to CMOS pipe CMOS ₂Drain electrode, CMOS manages CMOS ₂Source electrode be connected to battery pack U ₂Negative pole, CMOS manages CMOS ₂Grid be connected to driving stage P ₂, by driving stage P ₂According to optical receiver OR ₂The binary system control command that encoder the sent control CMOS pipe CMOS that is received ₂Break-make.CMOS manages CMOS ₂Work on off state, as CMOS pipe CMOS ₂High potential of grid input the time, CMOS manages CMOS ₂Conducting, battery pack U ₂Negative pole be equivalent to receive sustained diode ₂Positive pole.Sustained diode ₂The voltage at two ends is U ₂, the upper end is for just, and the lower end is for negative.As CMOS pipe CMOS ₂Electronegative potential of grid input the time, CMOS manages CMOS ₂End.Sustained diode ₂The voltage at two ends is diode junction voltage.

And the like, n direct voltage unit M _NComprise a battery pack U _N, a rectifier R _N, a sustained diode _N, an electronic switch and a driving stage P _N, electronic switch is CMOS pipe CMOS _N, described battery pack U _NPositive pole be connected in the negative pole of fly-wheel diode; Sustained diode _NPositive pole be connected to CMOS pipe CMOS _NDrain electrode, CMOS manages CMOS _NSource electrode be connected to battery pack U _NNegative pole, CMOS manages CMOS _NGrid be connected to driving stage P _N, by driving stage P _NAccording to optical receiver OR _NThe binary system control command that encoder the sent control CMOS pipe CMOS that is received _NBreak-make.Metal-oxide-semiconductor CMOS _NWork on off state, as CMOS pipe CMOS _NHigh potential of grid input the time, CMOS manages CMOS _NConducting, battery pack U _NNegative pole when in receiving sustained diode _NPositive pole.Sustained diode _NThe voltage at two ends is U _N, the upper end is for just, and the lower end is for negative.As CMOS pipe CMOS _NElectronegative potential of grid input the time, CMOS manages CMOS _NEnd sustained diode _NThe voltage at two ends is diode junction voltage.

The 1st direct voltage unit M ₀With the 2nd direct voltage unit M ₁Between with afterflow coil L ₀₁Link to each other, i.e. afterflow coil L ₀₁Be connected in sustained diode ₀Negative pole and sustained diode ₁Positive pole between; The 2nd direct voltage unit M ₁With the 3rd direct voltage unit M ₂Between with afterflow coil L ₁₂Link to each other, i.e. afterflow coil L ₁₂Be connected in sustained diode ₁Negative pole and sustained diode ₂Positive pole between; And the like, the 3rd direct voltage unit M ₂With the 4th direct voltage unit M ₃Between with afterflow coil L ₂₃Be connected.So, if each direct voltage unit M ₀, M ₁, M ₂... and M _NElectronic switch all under the situation of conducting simultaneously, the total output total voltage of direct current modulation power source is U _Always=U ₀+ U ₁+ U ₂+ ... + U _NThe magnitude of voltage of each direct voltage unit output is identical among the present invention, then total output voltage U _Always=nU ₀

Among the present invention, amplitude prediction decision device is successively with x _kAmplitude and each A _T1, A _T2... and A _TnCompare, if x _kAmplitude less than A _T1, corresponding binary code of encoder output, the electronic switch conducting of a direct voltage unit, the electronic switch of other direct voltage unit ends, and the power supply that the direct current modulation power source provides to final stage power amplifier is U _Always=U ₀If x _kAmplitude be greater than or equal to A _T1And less than A _T2, corresponding binary code of encoder output, the electronic switch conducting of two direct voltage unit, the electronic switch of other direct voltage unit ends, and the total output total voltage of direct current modulation power source is U _Always=2U ₀If x _kAmplitude be greater than or equal to A _Tn-1And less than A _Tn, corresponding binary code of encoder output, all direct voltage unit M ₀, M ₁, M ₂... and M _NThe equal conducting of electronic switch, the total voltage that the direct current modulation power source provides to final stage power amplifier is U _Always=nU ₀

Fig. 4 provides the oscillogram of electric energy when being final power amplifier amplifying signal provided by the invention.As shown in Figure 4, as the signal u that will launch _FAmplitude when big, can make all conductings simultaneously of electronic switch of each direct voltage unit, the power supply U that provides _AlwaysBe each power supply sum.As the signal u that will launch _FAmplitude hour, can make the part power turn-on, the power supply U that provides _AlwaysBe each direct voltage unit sum of conducting, that is, the voltage that provides is little, so, has just improved the utilance of power supply.

Though below in conjunction with the accompanying drawings the present invention has been done to elaborate, it should be recognized by those skilled in the art that do not breaking away under the prerequisite of the present invention design that any improvement of making based on the present invention and conversion still belong to the content in the protection range of the present invention.

Claims (4)

1. direct current modulation power source ofdm communication system that is used for unmanned plane, it comprises transmitter and receiver, described transmitter comprises: exciter, amplitude prediction decision device, encoder, the direct current modulation power source, the final power amplifier that the signal that is used for will sending exciter carries out power amplification, be used for the output filter that the input impedance of the output impedance of final power amplifier and transmitting antenna is mated and be used for that the signal of telecommunication through the final stage power amplification become magnetic signal and be transmitted into the transmitting antenna in space, described receiver comprises: the reception antenna that is used for the space magnetic signal is become the signal of telecommunication, the small signal amplifier that the signal of telecommunication that is used for that reception antenna is received amplifies, be used for the local oscillation signal that small signal amplifier institute's amplifying signal and first oscillator at the corresponding levels are produced is carried out first frequency mixer that down-conversion forms intermediate-freuqncy signal, be used for intermediate-freuqncy signal is carried out the A-D converter that analog to digital conversion forms data-signal, be used for removing the time interval of data-signal, then carry out serial to parallel conversion successively, the symbol inverse mapping device that the ofdm demodulator of FFT conversion and parallel serial conversion and the signal that is used for that ofdm demodulator is exported carry out the symbol inverse mapping, it is characterized in that, amplitude prediction decision device compares the instantaneous amplitude and the set point of the signal that exciter will send, and sends comparative result to encoder; The encoder compared result formation binary code of encoding, the direct current modulation power source provides electric energy according to binary code to final power amplifier.

2. require the 1 described direct current modulation power source ofdm communication system that is used for unmanned plane as requested, it is characterized in that, described direct current modulation power source comprises n level direct voltage unit, each direct voltage unit is by the cascade of afterflow coil, each direct voltage unit comprises a battery pack, a fly-wheel diode, an electronic switch and a driving stage, and the positive pole of battery pack is connected to the negative pole of fly-wheel diode; The positive pole of fly-wheel diode is connected to first end of electronic switch, second end of electronic switch is connected to the negative pole of battery pack, the control end of electronic switch is connected to driving stage, driving stage is according to the break-make of the binary code control electronic switch that encoder provided, and described n is greater than or equal to 2 integer.

3. require the 2 described direct current modulation power source ofdm communication systems that are used for unmanned plane as requested, it is characterized in that, exciter comprises symbol mapper, the OFDM modulator, the D/A translation circuit, second frequency mixer, second oscillator at the corresponding levels and the prime amplifier, wherein, the serial binary code stream that symbol mapper is used for being imported divides into groups to form data symbol and data symbol is mapped to the complex data data sequence, the OFDM modulator is used for institute's complex data data sequence serial to parallel conversion and is modulated to N subcarrier, then carry out the IFFT conversion and form parallel time domain data, i.e. Bing Hang OFDM symbol, described parallel time domain data is carried out the OFDM symbol that parallel serial conversion forms serial, then the OFDM of each serial intersymbol insert guard time form at interval serial insertion guard time OFDM symbol data streams at interval; The D/A translation circuit carries out digital-to-analogue conversion with data flow and forms analog signal u _iSecond frequency mixer is used for analog signal u _iLocal oscillation signal u with the second oscillator generation at the corresponding levels ₀Carry out up-conversion and form signal u to be sent _h, prime amplifier is to sent signal u _hAmplify and give final power amplifier and carry out power amplification.

4. according to the described direct current modulation power source ofdm communication system that is used for unmanned plane of claim 1 to 3, it is characterized in that described battery pack is a solar battery group.

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