CN1239350A - Load regulation technique and its communication method - Google Patents

Abstract

The present invention relates to a carrier modulation technique in radio communication, which features use of non-polar conversion mode to modulate amplitude, omitting the current direction conversion process for carrier and modulating signal, or eliminating the process thatthe current direction of carrier changes with the voltage direction of modulating signal, resulting in that the frequency of amplitude-modulated waves can not change, that is, the original frequency of carrier does not change. As a result, the communication does not possess band width, that is, more channels of signals can be transmitted in orginally possessed band width, including amplitude-modulated stereo sound, stereo TV and high-resolution TV.

Description

Carrier modulation technique and communication means thereof

The present invention relates to a kind of radio communication technology

The shortcoming of the existing radio communication technology is a lot.Aspect amplitude modulation communication, the upper and lower side frequency that as everybody knows, the amplitude modulated wave frequency is carrier frequency and frequency modulating signal addition, subtract.The double-side band communication of this technology, the frequency bandwidth that takies is the twice of high modulation signal frequency.In transmitting the higher communication of signal frequency, the frequency spectrum resource that takies is a lot.For example: the transmission of a cover TV programme, the frequency spectrum resource that takies is about as much as 8 times of medium wave broadcast frequency range, the needs of the incompatible a large amount of from now on development communications of this communication technology.This communication technology is subjected to the restriction of set occupied bandwidth and the broadcasting of failing to carry out compatible amplitude-modulated stereo, compatible 3-D TV and high definition TV receives, and also fails to carry out the jamproof amplitude modulation communication of de-noising.From another point of view, existing amplitude modulation technology, the constant-amplitude carrier of band signal has not accounted for most of energy of transmitting power.Reach at 100% o'clock at amplitude modulation coefficient, the energy of two sidebands only accounts for 1/3 altogether, and power utilization is very low.Concerning frequency modulation communication, though can eliminate noise with margining amplitude technique at receiver, the bandwidth ratio amplitude modulation communication that frequency modulation communication takies is wideer, and spectrum utilization is uneconomical.And because the passband of receiver is very wide, when not reaching clipping point at weak output signal, noise jamming is with regard to especially severe (because noise is directly proportional with bandwidth) ... the existing communication shortcoming is many, all is rooted in the backwardness of modulation technique.

The present invention designs a kind of new modulation technique for the problems that solve existing communication.This technology is that signal is called in carrier wave.Remove to carry signal by carrier wave generation changes in amplitude, rather than carry signal, so be referred to as " transfer and carry " technology by last lower side frequency.Changes in amplitude only takes place in the amplitude modulation effect of present technique, and occurrence frequency does not change, and the amplitude modulation wave frequency is the carrier wave primary frequency, and this is a kind of technology that does not account for bandwidth.Obviously, present technique and existing amplitude modulation technique effect difference are: prior art amplitude-modulated wave occurrence frequency changes, and present technique amplitude-modulated wave not occurrence frequency changes.With regard to this meaning, the present technique effect is opposite with the prior art effect.Existing amplitude modulation technology is about 100 years of application in practice, and present technique is come out mutually on the contrary with the prior art effect suddenly, must be easy to puzzling, consequently negative resolutely surely.Because the present technique effect is opposite with the prior art effect, we can say that as if since prior art facts have proved establishment, present technique just is false.The establishment of two kinds of technology respectively has reason in fact, sees following explanation for details.

Now earlier the changes in amplitude of amplitude modulation and frequency change being got in touch the cosmic inventory Changing Pattern goes to say something.As everybody knows, cosmic inventory changes two types: quantitative change and qualitative change.Relate to existing amplitude modulation technology, changes in amplitude wherein belongs to quantitative change, and frequency change belongs to qualitative change.For example, medium wave and ultrashort wave, the ionosphere in the former high-altitude can reflect back into ground to it, and the latter can not get back to ground, and its character of electric wave of this explanation different frequency is different, therefore we can say that the variation of frequency belongs to qualitative change.Everybody also knows, quantitative change does not cause that qualitative change is the universal law of all things on earth, quantitative change exceeds the maximum and some qualitative change will take place, this is a particular law, the example of universal law is a lot, our daily necessities for example: the peanut oil in the jar, the shampoo in the bottle, the water in the pond ... all reduce with cost, increase with replenishing, qualitative change does not take place with the increase and decrease of quantity in them.The example of particular law as the blast of atom bomb, is that quantitative change arrives to a certain degree and the generation qualitative change.In the mathematics category, many and few variation belongs to quantitative change, and the variation of being and not being belongs to qualitative change.Be 0 value that changes to of quantity, belong to qualitative change.Find as long as the quantitative change things of qualitative change thereupon then to have plenty of that quantitative change oversteps the extreme limit a little and things that qualitative change takes place between universe as yet.These rules of cosmic inventory have at first inspired the author to believe firmly the amplitude modulation that can carry out not frequency conversion in the limit, and with regard to the promotion that is subjected to this inspiration and effort, the author finds out the root that prior art amplitude-modulated wave occurrence frequency changes finally and finds and realize basis of the present invention.

Why not frequency conversion of why frequency conversion of prior art amplitude modulation, present technique amplitude modulation, this problem is done detailed explanation below in conjunction with all things on earth Changing Pattern and circuit theory.

Problem for convenience of explanation, earlier what the activity of electronics being distinguished is quantitative change, qualitative change.Undoubtedly, the fluctuating of voltage (promptly strong and weak the variation) belongs to quantitative change, just with negative variation (sense of current changes or title reversal), belongs to qualitative change.

Why occurrence frequency changes for the ease of the amplitude modulation of explaining prior art, is mixed down example in conjunction with Fig. 1 with large-signal earlier now, describes the frequency conversion operation principle.Figure (a) and figure (b) time of providing are the signal voltage of two different frequencies of 1 second, υ ₁, υ ₂, υ wherein ₁The waveform that 8 cycles are arranged, υ ₂The waveform that 10 cycles are arranged, 0 to t ₁During this period of time, the polarity of two signals is identical, and the amplitude of addition is greater than the amplitude of individual signals, because υ ₁Frequency lower, its phase place more and more lags behind υ ₂, t ₁Afterwards, the amplitude of addition becomes more and more littler, at t ₂To t ₃During this period of time, the polarity of two signals is opposite basically, and the amplitude of addition is less than the amplitude of individual signals.Crossed t ₃Afterwards, two signals from polarity on the contrary to the polarity identical change, at t ₄To t ₅Section in the time, the polarity of two signals basically identical that becomes again, the amplitude of addition are again greater than the amplitude of individual signals.Figure (C) provides υ ₁+ υ ₂Waveform.Scheme (C) as can be seen, the signal amplitude after the addition is big, for a moment little for a moment, in 1 second, fades to minimum by maximum, by being minimal to maximum, repeats twice altogether again, and this is the poor of two signal frequencies, is called beat.To sum up describe, the generation of figure (C) waveform is that two signals carry out reversal, periodically conversion in the same way with oppositely form.In other words, this is the result that signal carries out reversal.If υ ₁υ ₂Two signals are to be added on the non-linear element, for example add to a transistorized input, and make transistorized quiescent point be near cut-off point (just being in the characteristic curve zone), so υ ₁+ υ ₂During negative value, base current is 0, just obtains the waveform shown in the figure (d).Current i is decomposed, can tell a waveform i shown in figure (e) ₁, i ₁Frequency equal υ ₂With υ ₁Poor, be 2 hertz.i ₁Be the difference frequency electric current.Also have in addition and the frequency electric current, be not easy on the figure to find out significantly.Current i ₁Be that figure (C) waveform adds on the non-linear element and obtains, this explanation and with the difference frequency conversion, be two signals carry out reversal in the characteristic curve zone of non-linear element result.

Relate to the frequency conversion of amplitude modulation process, in fact, under " large-signal " mixing situation, transistorized operating state is similar to transistorized operating state under the emitter junction control amplitude modulation situation.On effect, amplitude modulation situation and frequency conversion situation all produce the frequency of two input signals itself and with frequently with difference frequency etc.When amplitude modulation, we choose the higher carrier wave of its medium frequency and two side frequencys, then only choose one of them side frequency " with frequency or difference frequency " during mixing.Thanking to unit's loyal the 263rd page of the 9th row of " transistor high-frequency circuit " volume two of compiling of clear nationality justice writes: " difference of amplitude modulation and mixing only is that the frequency selection circuit of output is different ".The amplitude modulation of this explanation prior art is identical with mixing work, all is two signals carry out reversal in the characteristic curve zone of non-linear element result, concerning the frequency conversion of amplitude modulation, is the result that carrier wave and modulation signal carry out reversal.

Correct in order to prove above-mentioned judgement, existing a kind of modulation circuit of knowing well with masses according to the amplitude modulation principle that the technician should understand, is drawn and is popularly understood, and modulation signal is the amplitude-modulated wave waveform that reversal and nonpolarity conversion are arranged, relatively two kinds of amplitude modulation results.Fig. 2 is the annular balance amplitude modulator that masses know well and understand its operation principle.Everybody understands, the amplitude modulation work of this modulation circuit is the switching function that utilizes element (diode), by carrier voltage control D ₁D ₂With D ₃D ₄Taking turns switch by the frequency of carrier wave, to shift the frequency characteristic of carrier wave, is the modulation signal voltage transitions amplitude voltage of carrier wave.This modulation circuit is not when having the modulation signal input, and carrier wave is output as 0, so the amplitude voltage of amplitude-modulated wave equals modulation signal voltage.But because figure a and the modulation signal different in kind of scheming b, the difference as a result of amplitude modulation.Modulation signal that please first a with the aid of pictures, this is the modulation signal that reversal is arranged, T ₁T ₇T ₁₃Carry out the O point excessively of reversal for modulation signal.Please see Figure the modulation signal of b, whenever its voltage curve all is in the top of abscissa, all belongs to forward voltage, and its variation is the fluctuating of forward voltage always, and this is the signal of nonpolarity conversion.Waveform that please first b amplitude-modulated wave with the aid of pictures, envelope shape meets the modulation signal waveform, can directly examine signal with envelope detection.Contrast the carrier wave of input, whenever all follow the sense of current of primary carrier, the amplitude modulated wave frequency is identical with original frequency of carrier as can be known, reaches to transfer to carry a purpose.Present a amplitude-modulated wave with the aid of pictures, its envelope shape does not meet the modulation signal waveform, can not directly examine signal with envelope detection, and but this is that masses know well carries an amplitude-modulated wave.As everybody knows, the upper and lower side frequency that press down to carry the amplitude modulation wave frequency and be carrier frequency and frequency modulating signal addition, subtracts, amplitude-modulated wave has become frequency.The frequency conversion that please see it is from where producing, by observing as seen, at T ₇Locate, the carrier wave and the incoming carrier of output are anti-phase, and the frequency conversion of amplitude-modulated wave is at T as can be known ₇The place produces, and T ₇Be the O point excessively that modulation signal carries out reversal, frequency conversion of this explanation amplitude-modulated wave is the result that modulation signal carries out reversal.Everybody also knows, the amplitude-modulated wave of Fig. 2 a that we see, and actual is the average frequency of going up lower side frequency, and this waveform is a synthetic waveform of going up lower side frequency, and we can obtain upper side frequency or lower side frequency with frequency selection circuit.Problem is now amplified the amplitude-modulated wave of Fig. 2 a with Fig. 3 for convenience of explanation, and dotted line A, A ' draw in the both sides of abscissa.If with dotted line A is abscissa, visible T ₇Electrical voltage point leave abscissa, T ₆To T ₈Magnitude of voltage all be in the same side of abscissa, T ₆To T ₈The negative half period voltage of the synthetic distortion of voltage, this compares with former incoming carrier, has lacked half cycle voltage.The one-period of modulation signal had crosses the O point twice, has lacked all voltage altogether, and all numbers of minimizing equate that with all numbers of modulation signal new life's frequency equals carrier frequency and subtracts frequency modulating signal, the lower side frequency of Here it is amplitude-modulated wave.If with A ' is abscissa, visible T ₇Electrical voltage point is in T ₆With T ₈The opposite side of electrical voltage point, T ₆To T ₈The negative half period voltage of two distortions and the positive half cycle voltage of a distortion appear during this time, this compares with former incoming carrier, many half cycle voltages, the one-period of modulation signal is many altogether all voltage, the all numbers that increase equate with all numbers of modulation signal, newborn frequency equals carrier frequency and adds frequency modulating signal, the upper side frequency of Here it is amplitude-modulated wave.If the amplitude-modulated wave input of figure a is tuned in the frequency selection circuit of lower side frequency, because its resonance frequency is lower, T ₇Change in voltage rapidly is subjected to the control of tuning circuit, T ₆To T ₈Voltage even up, " shaping " through oversampling circuit obtains distortionless lower side frequency.If the input of figure a amplitude-modulated wave is tuned in the frequency selection circuit of upper side frequency,, adapt to T because its resonance frequency is higher ₇The voltage sudden turn of events, make T ₇Voltage remains in forward, and " shaping " through oversampling circuit obtains distortionless upper side frequency.

As can be known with the aid of pictures, the amplitude modulation of Fig. 2 a why occurrence frequency changes, be because modulation signal carry out reversal time changing the carrier voltage direction of output.Point out that above reversal belongs to qualitative change, therefore we can say the amplitude modulation effect of prior art qualitative change (frequency change) with the qualitative change of modulation signal.

In sum, the reversal of modulation signal, it is the root that causes the amplitude-modulated wave occurrence frequency to change, therefore, realize the amplitude modulation of not frequency conversion, must turn to modulation signal the signal of nonpolarity conversion, the amplitude modulation process be disappeared as the mixer action of Fig. 1, promptly eliminate carrier and modulating signal changes current direction of carrier with reverse periodicity transfer process and elimination in the same way owing to the modulation signal voltage direction as Fig. 2 a process.

Realize the amplitude modulation shown in Fig. 2 b, can connect positive source to the point of the m among the figure, the n point connects the collector electrode of npn type triode, and base stage adds suitable bias current, the input point (see figure 4) of base stage as modulation signal.As seen with the aid of pictures, Fig. 4 and common annular balance amplitude modulator difference are to connect a triode more, and the task of this triode is the signal that modulation signal is turned to nonpolarity conversion, make to be added to the fluctuating that signal that amplitude modulator n orders has only voltage, do not have the conversion of polarity.

For the ease of the back mathematical derivation, particularly point out now, Fig. 4 amplitude modulator ifs circuit element is desirable, (input point of modulation signal is not during making alive there not being modulation signal when input, be that the base stage of Fig. 4 is not when adding bias current), although the carrier wave of input is enough strong, the carrier wave of amplitude modulator output is 0.But if base stage adds bias current, this just is equivalent to add the modulation signal of stationary value, and carrier wave output is at this time arranged.The purpose that adds bias current is to make the amplitude-modulated wave envelope meet the modulation signal waveform, guarantees undistorted.

Now derive present technique amplitude-modulated wave mathematic(al) representation at the amplitude modulation of Fig. 4.Elder generation's citing document sees how vertical prior art amplitude-modulated wave instantaneous value expression formula is.Please see and to take passages below, in " radio amateur's reader " that Chinese Institute of Electronics compiles volume walk to for the 105th page the 20th the literal of the 26th row and expression formula " ... be moment of 0 as modulation signal aF (t); (amplitude modulator output) carrier amplitude A (t) still is Af; so the instantaneous value of amplitude-modulated wave envelope should be A (t)=Af (t)+aF (t); so, the instantaneous value expression formula of amplitude-modulated wave just should be a (t)=A (t) sin ω _oT=(Af+aF (t)) sin ω _oT ... ", there are two of carrier amplitude Af and modulation signal aF (t) in the amplitude-modulated wave instantaneous value expression formula of visible prior art, why has one of Af, is because modulation signal is 0 o'clock amplitude modulator carrier wave output to be arranged.Point out above the amplitude modulation of present technique, modulation signal is 0 o'clock, there is not carrier wave output, therefore the present technique expression formula should (at first illustrate the inapplicable present technique of prior art mathematic(al) representation field here according to the Af that following formula deducts in the bracket of second equal sign the right, the reader can not take the prior art mathematic(al) representation be " according to ", go negative present technique amplitude modulation effect).Because the aF (t) of following formula is a modulation signal,, just should use the aF (t) in the bracket of AV substitution following formula second equal sign the right if therefore be added to the modulation signal voltage that n is ordered by triode with AV representative graph 4.By said reason, above-cited prior art expression formula is deducted in the bracket first, in the substitution bracket second must present technique amplitude-modulated wave instantaneous value expression formula: a (t)=AVsin ω _oT, AV is a modulation signal voltage in the formula.Now remark additionally, above-mentioned citing document is made modulation signal substitution aF (t) with AFsin Ω t, and its substitution is a sinusoidal ac.Must point out seriously that the substitution formula of present technique can not be exchanged with prior art substitution formula, because the modulation signal different in kind of two kinds of technology.Wherein the present technique modulation signal of nonpolarity conversion has only unidirectional change in voltage, does not have the conversion of the sense of current, does not possess the characteristic of alternating current.The different in kind of two modulation signals, it is different with instantaneous value obviously to find expression in absolute value.T with Fig. 2 ₁, T ₇, T ₁₃Be example, the modulation signal of wherein scheming a is 0 value, and the modulation signal of figure b is the median of positive voltage, rather than 0 value.Since the different in kind of modulation signal, that just must be respectively with the substitution formula substitution aF (t) that meets its modulation signal character.The modulation signal of present technique has only change in voltage, does not have the conversion of the sense of current, so present technique amplitude-modulated wave instantaneous value expression formula should be with the AV substitution aF (t) of representative voltage only, can not be with both containing the AFsin Ω t substitution that amplitude A F also contains angular frequency Ω.Because the substitution formula should be different, this illustrates the inapplicable present technique of prior art mathematic(al) representation field once more, can not force at present technique to the amplitude modulation effect that the prior art mathematical expression is expressed.

Deep and thorough in order to explain, must remake at two kinds of modulation signals shown in Fig. 2 a Fig. 2 b and explain.Please first 2c with the aid of pictures, this is the primary signal of modulation signal.Two kinds of modulation signals shown in the figure a figure b, be by figure c primary signal change or the signal of telecommunication.Please see Figure the original signal waveform shown in the c, T ₄Be crest (maximum), T ₁₀Be ripple valley (minimum value), T ₁, T ₇, T ₁₃Be ripple waist (median).Please see Figure the signal of telecommunication of b, this signal occurs with positive voltage, T ₄Be maximum, T ₁₀Be minimum value, T ₁, T ₇, T ₁₃Be median, meet original signal waveform.Please see Figure the signal of telecommunication of a, meet the waveform of figure c primary signal seemingly, essence does not meet original signal waveform.This signal of telecommunication T ₄Be the maximum of positive voltage, T ₁₀Be the maximum of negative voltage, T ₁, T ₇, T ₁₃Be 0 value (minimum value), rather than median.The signal of telecommunication of figure a is the signal that does not meet the rotten distortion of original signal waveform.Why the amplitude-modulated wave of figure a can not directly examine signal with envelope detection, because this is the amplitude-modulated wave of distorted signal.Figure a obviously can see, rotten (distortion) of modulation signal, and amplitude modulation is brought two disastrous effects: one, envelope does not meet the waveform of primary signal; Two, qualitative change (frequency change) has taken place in amplitude-modulated wave.To provide an experimental result to prove this point more below.As everybody knows, figure a amplitude-modulated wave adds after the constant-amplitude carrier, can examine signal with envelope detection.Why? because constant-amplitude carrier voltage that adds and in the same way amplitude-modulated wave voltage addition, subtract each other with reverse amplitude-modulated wave voltage, T ₁, T ₇, T ₁₃The amplitude-modulated wave magnitude of voltage bring up to median, T ₁₀The reverse amplitude-modulated wave of amplitude maximum drops to minimum value, makes envelope shape meet the waveform of primary signal.The constant-amplitude carrier that adds plays the effect of correcting distortion.Therefore all usefulness has the signal demodulation of reversal, amplitude-modulated wave all must have the component of constant-amplitude carrier to mix mutually, in conjunction with modulation circuit and amplitude-modulated wave mathematical expression, modulation circuit must have former constant-amplitude carrier output, and mathematic(al) representation must have the composition and the plus sige of former constant-amplitude carrier.Modulation signal is the amplitude modulation of nonpolarity conversion, owing to need not the carrier wave superposition of constant amplitude, when circuit design just should make no modulation signal import when making alive (input point of modulation signal not), the carrier wave of no constant amplitude is exported, mathematic(al) representation does not just have the composition of constant-amplitude carrier, no add operation symbol.Above-mentioned first disastrous effect that is caused by the rotten distortion of modulation signal can be by just keeping former constant-amplitude carrier deemphasis, but amplitude-modulated wave has become disastrous effect frequently then can't be remedied, therefore necessary signal demodulation with nonpolarity conversion, this can solve two problems at one stroke, realizes our purpose.

Above the mathematical expression of two kinds of amplitude modulation technology show that the amplitude modulation of prior art is (carrier wave and modulation signal) energy addition, the amplitude modulation of present technique is power conversion, promptly is the modulation signal voltage transition amplitude voltage of carrier wave.Obviously, the amplitude modulation of Fig. 2 a also is power conversion, its amplitude-modulated wave mathematic(al) representation should not have the carrier wave composition of former constant amplitude yet, but modulation signal is the alternating current that reversal is arranged, therefore mathematical expression should have the amplitude (AF) and the angular frequency (Ω) of its modulation signal, because amplitude and angular frequency are the fundamentals in the alternating current three elements, the prior art mathematic(al) representation of the 105th page of the 27th row of top citing document is made modulation signal substitution aF (t) with AFSin Ω t, like this, the mathematical expression of Fig. 2 a amplitude-modulated wave has been Duoed the composition of Sin Ω t than the present technique mathematical expression except the AF that contains voltage character.Therefore the amplitude-modulated wave of Fig. 2 a just becomes (ω _o+ Ω) and (ω _o-Ω) last lower side frequency.

In sum, carrier modulation technique is characterised in that: the modulation signal with nonpolarity conversion is carried out amplitude modulation.The amplitude modulation working procedure earlier turns to modulation signal the signal of nonpolarity conversion, the signal voltage of nonpolarity conversion input modulation circuit is changed into the amplitude voltage of carrier wave again.The handlebar modulation signal turns to the device of the signal of nonpolarity conversion in the circuit.

According to top explanation, we can say that the modulation signal that reversal is arranged is the signal that has quantitative change (voltage fluctuation) and qualitative change (reversal).The signal of nonpolarity conversion has only quantitative change, does not have qualitative change.But point out with the mathematics idea that above it is exactly qualitative change that the variation of amount arrives 0 value.Therefore must be pointed out,, qualitative change has taken place exactly if the voltage fluctuation of nonpolarity conversion drops to 0 value.The all things on earth particular law of qualitative change will take place to a certain degree in quantitative change that Here it is.Just because like this, experiment showed, the amplitude modulation work of Fig. 4,, make during the input of modulation signal negative half period that a period of time is (as the T of Fig. 5 if the modulation signal of input base stage is strong excessively ₉To T ₁₁During this period of time), the transistor collector electric current is 0, i.e. the rotten distortion of modulation signal (this is actual to be to surpass 100% amplitude modulation) is gone up lower side frequency so amplitude-modulated wave with regard to frequency conversion, becomes.This just fully proves amplitude modulation effect qualitative change with the qualitative change of modulation signal (frequency change).Explanation thus, as long as the rotten distortion of modulation signal, amplitude-modulated wave is with regard to frequency conversion.Therefore special prompting reader should control modulation depth in practice and deny admission to the frequency conversion state.Above-mentioned experimental result proves, modulation reaches 100% limit point that changes for occurrence frequency not.Be referred to as amplitude modulation " frequency conversion critical point ".

By above-mentioned operation principle, the accent live road that can implement is a lot, now lifts three examples, sees Fig. 6, Fig. 7, Fig. 8, and wherein Fig. 6 is best enforcement figure.These circuit, as the technician, explanation above readding should be understood and can implement, and does not now describe its amplitude modulation work.Wherein Fig. 6 and Fig. 7 serve as switch work by diode, shift the frequency characteristic of carrier wave, and the task of triode is the signal that modulation signal is turned to nonpolarity conversion.Fig. 8 serves as switch work by npn type triode, shifts the frequency characteristic of carrier wave, serves as the signal that modulation signal is turned to nonpolarity conversion by pnp type triode.By above-mentioned operation principle, also can form the accent live road (summary) that need not coil transformer, therefore can use crystal filter, realize communication apparatus microminiaturization.Also can not utilize the switching function of element to go to carry out amplitude modulation, be applicable to the amplitude modulation work of any high frequency.

Carrier modulation technique can be carried out compatible amplitude-modulated stereo broadcast reception.As everybody knows, world technology circle has been done a lot of research work for the stereophonic broadcasting of realization medium wave.As far back as nineteen twenty-six, AT﹠T just proposed orthogonal modulation scheme, and to middle nineteen seventies, the U.S. proposed five kinds of schemes such as shellfish drawing, Cann system again.1984, overtesting was also done to some medium wave amplitude-modulated stereo broadcast systems by Chinese Huanan (South China) Polytechnic College and Nanjing Polytechnical College, does not obtain satisfactory effect always.Why can't realize, be because the set occupied bandwidth of amplitude modulation broadcasting is too narrow after all.To rise on November 23rd, 1978, whole world medium wave am broadcast is unified specified channel and is spaced apart 9KHZ, the receiver passband must be narrower than 9KHz, like this, it is exactly the monophonic broadcasting of prior art, can not the higher audio signal of transmitted frequency, therefore existing amplitude modulation broadcasting has lacked the higher sound of frequency, abundant less than FM broadcasting aspect tonequality, does the broadcasting of the satisfactory implementation two paths of signals of what energy receive? obviously, carrier modulation technique can transmit the signal of any high frequency owing to do not account for bandwidth in any arrowband, present technique can receive in satisfactory implementation stereophonic broadcasting.Aspect technical finesse, in order to separate two paths of signals, wherein one road signal transmits by subcarrier, and receiver is through twice demodulation picked up signal.But subcarrier frequency is up to several times of audio signal, and the transmission of subcarrier must just can guarantee not expand occupied bandwidth with carrier modulation technique.Can be narrow arbitrarily for the passband that carries out the transition to receiver, enable farthest to reduce noise jamming and suppress and mix, should manage to finish whole signals and transmit with single carrier wave.Intend alternating voltage control for this reason, transmit the two paths of signals amplitude-modulated wave in turn with 38KHZ.Obtain all audio frequency signal in order to allow monophony receive function, transmitting terminal is transformed into left and right sound track signals and difference signal with matrix circuit, transmits in turn and the difference signal amplitude-modulated wave.In it and signal directly to carrier wave amplitude modulation, difference signal is called in main carrier to modulated subcarrier more earlier to subcarrier amplitude modulation.The frequency of subcarrier intends getting 76HKZ.Receiver is through a detection acquisition and signal, and after twice detection obtained difference signal, to doing the balance adjustment with difference signal, the input matrix circuit conversion went out left and right sound track signals then.The 76KHZ subcarrier of transmitting terminal is made two frequencys multiplication by 38KHZ switch AC electricity and is got.Take turns streamed per service time in step, let slip the amplitude-modulated wave of subcarrier one-period.For paces are accurate, must do suitable phase place adjustment to switching signal.

Compatible amplitude-modulated stereo transmitter-side block diagram is seen Fig. 9, among the figure 1.2 is respectively left and right sound track signals, two sound channel signal input matrix circuits 3 are transformed to and difference signal, circuit 4,5 is respectively and the difference signal path, circuit 6 is a carrier wave generation circuit, and carrier wave input modulation circuit 7 circuit 4 and signal and circuit 6 carries out amplitude modulation.Circuit 8 is a switching signal generation circuit, and circuit 9 is switching signal two frequency multiplier circuits, is used as subcarrier after frequency multiplication.The subcarrier input modulation circuit 10 of the difference signal of circuit 5 and circuit 9 carries out the amplitude modulation first time, the modulated subcarrier input circuit 11 of the main carrier of circuit 6 and circuit 10 carries out the amplitude modulation second time, the switching signal input of circuit 8 is merged circuit 12, the control electronic switch takes turns the amplitude-modulated wave of input circuit 7 circuit 11, and circuit 13 is the carrier wave amplifying circuit.

Figure 10 is the receiver block diagram.Wherein circuit 1 is the carrier wave amplifying circuit, circuit 2 is a detecting circuit, examine with signal and subcarrier respectively input circuit 3,4 serve as and signal amplifies with the subcarrier frequency-selecting and amplifies, the subcarrier input detecting circuit 5 of circuit 4 carries out the detection second time, examine difference signal input amplifying circuit 6 fully be amplified to than after strong with signal, the input balance adjust circuit 7 do suitably to weaken make intensity with and signal-balanced, again with circuit 3 with signal input matrix circuit 8, conversion goes out left and right sound track signals, respectively input amplifying circuit 9, circuit 10.

Obviously, above-mentioned stereophonic broadcasting is compared with existing amplitude modulation broadcasting, also have three big advantages: one, because carrier modulation technique has been abolished the not constant-amplitude carrier of band signal, the information energy that equal transmitting power transmits is three times of existing amplitude modulation broadcasting, under the always limited reality of transmitting power, the acquisition of this effect is accomplished something difficult and so deserve praise; Two, the enhancing of amount of information brings the raising of receiving efficiency and the improvement of signal to noise ratio; Three, can any high voice signal of transmitted frequency, thereby wireless tonequality is abundant.Above-mentioned 3 points, existing amplitude-modulation receiver is benefited too.Two, the monophony amplitude-modulation receiver of the narrow arbitrarily a new generation of a kind of passband all after the reform, can also be released in the radio station, then wireless noise jamming seldom (because noise is directly proportional with bandwidth), and mixed easily platform.

Carrier modulation technique can be transformed TV, realizes three targets: one, carry out compatible 3-D TV and broadcast reception.As everybody knows, world technology circle has been spent many brains for the realization stereoscopic TV, tests shunting system, color-dividing system, in-turn system etc., but does not all obtain due effect because being subjected to the restriction of the existing set occupied bandwidth of TV.As everybody knows, the optimal stereoeffect of people is to blow against one's face as three-dimensional film, very the third dimension of irriate.On the other hand, must with existing TV compatibility, just with practical value.Obviously, utilize West Germany to like that general ground Hao Fu Man develops and redly prolong that formula colour TV three-dimensional device adopted, two images are introduced the method for right and left eyes respectively,, can realize these purposes in conjunction with carrier modulation technique with the colour filter method.Method is introduced in the red colour filter of prolonging formula three-dimensional device of West Germany, is with the blue or green right red goggles with color filter in a left side, and cyan (the green indigo plant that adds) and red two images are introduced right and left eyes respectively.Owing to the red formula of prolonging is to be divided into two kinds of not homochromy images artificially staggering about the image of the original same width of cloth.Facts have proved that this can only give a kind of third dimension to deepening behind the scenes of spectators.This third dimension does not meet spectators' pursuit, but verifiedly can introduce right and left eyes to blue or green, red two images light respectively with this colour filter method.Carrier modulation technique, can be under the prerequisite of not expanding occupied frequency bandwidth, transmit two picture intelligences of left and right sides lens shooting simultaneously, the image that this signal pattern and three-dimensional film two-shipper are taken is as good as, therefore can realize as the third dimension as the three-dimensional film, but in order to realize compatibility, can only allow the flat-surface television spectators see the image (for example image of left lens shooting) of one of them lens shooting, like this, left side camera lens image is watched for flat-surface television and stereoscopic TV spectators, right camera lens image is for double the seeing of stereoscopic TV spectators, and the former claims main picture, and the latter claims subpicture.In order to make the flat-surface television spectators can't see subpicture, the subpicture signal must transmit by subcarrier, makes through twice demodulation and could obtain the subpicture signal.As for the frequency of subcarrier, should be suitable, higherly then can not broadcast than low-frequency range, on the low side then can not the higher picture intelligence of transmitted frequency, and subcarrier is wanted jamming pattern.Clearly, if subcarrier is 6.5MHZ, just can thoroughly solve these contradiction.Because the 6.5MHZ of television set absorbs circuit and can absorb it.But the subcarrier of 6.5MHZ can not carry the picture intelligence up to 6MHZ.Through research repeatedly, to reach a conclusion, the subpicture signal frequency of transmission can be lower, and reason is, and stereoscopic TV spectators' left eye has been seen the pictorial detail up to 6MHZ, and the right vision deficiency has been done compensation by left vision.2.5 inches of stereo camera left and right sides distance of camera lens, the scenery of the overwhelming majority is all by two lens shootings, and the narrow and small scenery that the both sides, place are seen at a glance (i.e. the scenery of a lens shooting) is the careless scenery of human eye vision, does not perceive its careful appearance.Facts have proved that right camera lens picture intelligence can be compressed to 1.3MHZ as the chrominance signal frequency spectrum.

The left camera lens picture intelligence of compatible 3-D TV, encoded routinely device forms after the composite colour television signal, and to carrier wave amplitude modulation, right camera lens picture intelligence can only transmit red signal.When the spatical television set user watches three-dimensional program, stir three-dimensional switch,, connect (red) signal path of right camera lens so the input of the red efferent duct of television set cuts off the red signal path of left camera lens.At this time the left camera lens signal of television set input picture tube has only green, blue signal (synthetic cyan), and the right camera lens signal of input picture tube is a red signal.Spectators put on the blue or green right red goggles with color filter in a left side, and the cyan image light of left camera lens is introduced left eye, the red visual light introducing right eye of right camera lens, can obtain the third dimension as the three-dimensional film.

The picture intelligence of stereoscopic TV is owing to all carry out amplitude modulation with carrier modulation technique, thereby eliminated constant-amplitude carrier, and receiver should not lean on beat to produce 6.5MHZ sound accompaniment frequency-modulated wave.Therefore sound accompaniment should take the FM.AM record and broadcast to send, by the envelope detection of receiver examine 6.5MHZ sound accompaniment frequency-modulated wave.The subpicture carrier wave takes China in the secondary audio carrier wave by the ministerial level authorization in 1987, the high 0.242MHZ of its frequency ratio sound carrier, but must carry out amplitude modulation with carrier modulation technique, to guarantee not expand occupied bandwidth.Though the secondary audio carrier wave by the ministerial level authorization has been used as the subpicture carrier wave, but available another kind of processing method is carried out two stereo broadcastings of sound accompaniment, method is to take the two divided-frequency 2.215MHZ control electronic switch of colour subcarrier 4.43MHZ, transmits the left and right sound track signals amplitude-modulated wave in turn.Existing television set sorts without electronic switch, unified two sound channel signals of receiving.Stereo-television receiver sorts out left and right sound track signals with the two divided-frequency 2.215MHZ control electronic switch of colour subcarrier 4.43MHZ, and this just obtains stereo, and stereoscopic image is joined stereo, and impression is more true to nature; Two, carry out compatible high definition TV (HDTV) and broadcast reception.It is reported, the seventies HDTV that just begins one's study in the world, China begins the research work of HDTV in late nineteen seventies.19 countries in Europe once jointly invested 1.86 hundred million dollars of research HDTV.The production technology of picture tube now can satisfy the demand of high definition TV, receives but fail the broadcasting of satisfactory implementation HDTV so far.Obviously, a wherein the most basic difficult problem is the frequency spectrum occupation problem, will transmit the picture intelligence of upper frequency because promote clearness, increase the horizontal scanning line number, this all involves will expand the bandwidth that takies, carrier modulation technique has solved this problem fully, so we have reason to realize that with carrier modulation technique the broadcasting of HDTV receives.But realize receiving compatibility, must accomplish both can allow new product HDTV receiver increase the horizontal scanning line number, also do not change existing line synchronizing signal, do not increase line frequency with the broadcasting of existing TV.The solution of discussing this question below.

The horizontal scanning line scheme of counting of foreigner HDTV has two kinds: the scheme of states such as Japan is 1125 row, and the scheme of Europe alliance is 1250 row.The processing method of getting 1250 row just is discussed now.1250 row are the twice of existing TV 625 row of China just, we just utilize this multiple relation, and research realizes the processing method of this target, and this method is take interlacing scan to hold concurrently a way that interlacing inserts, the line scanning that makes existing TV still is 625 row, and the HDTV television set can obtain 1250 row.Interlacing scan is held concurrently work essence that interlacing inserts as shown in figure 11.The former odd-numbered line of 1.3 behaviors wherein, the former even number line of 2.4 behaviors, the odd-numbered line that 1 ', 3 ' behavior is inserted.The even number line that 2 ', 4 ' behavior is inserted.Explanation earlier, so-called " insertion ", actual is the position of mobile line scanning, the line scanning position to the centre that moves down into former 625 line scanning positions.Figure 12 as seen, this interlacing scan high definition TV that interlacing inserts of holding concurrently is a frame with four.Wherein P one, P two, P three, P four are respectively first, second, the 3rd, the 4th, and among these four, first and second scanning is displacement not.At the 3rd field time, the scanning position of electron beam will be got back to first position originally, but our facility makes it move down hemistich apart from the position, at the 4th field time, the scanning of electron beam will be got back to second position originally, but our facility makes it move down hemistich apart from the position, so finished the scanning of a frame, as seen from the figure, horizontal scanning line doubles, and is increased to 1250 row by 625 row, but from operation principle as can be known, the field frequency line frequency is constant, can with existing TV compatibility.

Above-mentioned scan line displacement, actual is to change deflection angle.According to deflection principle, the angular dimension of the electron beam deflecting is directly proportional with deflection current, and the electric current that therefore can increase and decrease deflecting coil removes to change deflection angle, realizes scan shift.Be in the stage of cutting on the fluorescent screen in scanning, the electric current that flow through deflecting coil originally is a negative sense, make scan line to moving down, reduce deflection angle exactly, will reduce the negative current of deflecting coil, we can add suitable forward current to deflecting coil, and synthetic negative current is reduced.Be in stage of following section of fluorescent screen in scanning, the electric current that flow through deflecting coil originally is a forward.Scan line is shifted downwards, increases deflection angle exactly, will add suitable forward current, the sense of current whenever this explanation adds is identical, and because horizontal scanning line is a straight line, the electric current of adding should be stable direct current.For the scan line that makes displacement just in time is embedded in the center of former scan line, it is suitable that the electric current of adding must be adjusted.Reset current is actual to be to add field deflection coil.

When add as for reset current, from Figure 12, the one or two need not add, and the three or four must add.Add and the conversion that does not add, for each frame transform of existing television system once, rather than by field transformation.Can be synchronous for the scanning that makes receiver with transmitting terminal, avoid the pixel hemistich apart from turning upside down, must the transmission identification signal to the scanning field of displacement.The identification signal frequency is got 5.5MHz, and this and colour subcarrier and sound subcarrier (6.5MHz sound accompaniment frequency-modulated wave) be at a distance of about 1MHz, separation easily.The delivery time of identification signal, transmit in a certain narrow groove (for example the 3rd narrow groove) time that field system chronizing impulse is opened.For guaranteeing not obscure with picture intelligence, the receiver time of taking earlier separates, and takes out identification signal in the time of field system chronizing impulse, removes other clutters and noise jamming with frequency selection circuit again.

The high definition TV of such scheme is a frame with four, and wherein the image of each is exactly the image that each scan line constitutes among Figure 12.Repeat every three.It is calculated that the summation of three field times does not surmount human eye vision and persists the time, proves technical feasibility.Above-mentioned processing method as can be known, the technological transformation of TV can realize that stereoscopic image, stereo sound accompaniment, high definition develop simultaneously; Three, reduce the bandwidth that TV takies in a large number, the program of a national each province and city hundreds of TV station is concentrated within the existing a certain channel (8MHz) transmit.TV user can only use the reception antenna of a certain channel, (but existing television receiver must the local TV of holder maintenance department be loaded onto special narrow band filter to select the program of seeing any TV in the whole nation arbitrarily, could receive at this dedicated channel, otherwise mix platform).After the transmitter-receiver of this reform is popularized, just can vacate and have a large amount of frequency spectrum resources that tens channels take now and be used to develop other communications.For this purpose, must move on to the distance of pix carrier and FM.AM system sound carrier from existing 6.5MHz the most approachingly, for example move on at a distance of 10KHz.This processing, the rule of giving free rein to will produce the 10KHz difference frequency and disturb, but the frequency conversion principle of understanding according to masses shown in Figure 1, we can take measures that this difference frequency is converted into television set 6.5MHz and absorb the frequency that circuit can absorb.Way is at transmitting terminal pix carrier or sound carrier to be done high speed paraphase processing with the speed of 6.5MHz, shorten two carrier waves in the same way with reverse transformation period, this just can not form the difference frequency of 10KHz, but can only become the absorption frequency of 6.5MHz ± 10KHz, also can go compensation at receiver with the gain that improves sound accompaniment in conjunction with the transmitting power that reduces sound carrier.Thereby more effectively reducing difference frequency disturbs.

Obviously, existing any amplitude modulation communication is used instead after the carrier modulation technique, and can obtain three big advantages: one, the constant-amplitude carrier of band signal improves power utilization owing to having abolished not; Two, the passband of receiver can be narrow arbitrarily because the transmission of signal does not account for bandwidth, thereby can reduce noise jamming; Three, saving takies frequency spectrum, enlarges message capacity.Especially digital communication more needs carrier modulation technique because simulate signal digitalized after frequency improve greatly, although prior art has taked various savings to take the measure of frequency spectrum, be not effective solution.

Modulation technique does not account for bandwidth owing to transmit the signal of any high frequency, therefore can be within any arrowband, by the subcarrier implements communication, to obtain following advantage: one, can carry out secure communication easily; Two, can get rid of the interference in other radio station by frequency-selecting to subcarrier; Three, because afterwards, can choose subcarrier with frequency selection circuit in the detection first time (envelope detection), although signal to noise ratio is any poor, noise can not flood signal (energy reinserted subcarrier), it doesn't matter " threshold effect ".Make amplitude modulation communication be applicable to the communication of any difference of signal to noise ratio; Four, in conjunction with frequency modulation technology, low frequency signal adopts mode of frequency regulation to the modulation of subcarrier, carry out the communication of FM.AM system, in the subcarrier amplifying circuit of receiver, excise residual noise with amplitude limiter, this has just utilized the strong point of frequency modulation communication, realization can be eliminated the amplitude modulation communication of noise, thereby decontrols the constraint of signal to noise ratio, improves the effect of amplitude modulation communication.And owing to still do not account for bandwidth, the passband of receiver also can be narrow arbitrarily, like this, and when weak output signal does not reach clipping point, noise jamming also considerably less (because noise is directly proportional with bandwidth), this is that existing frequency modulation communication is because the receiver passband is very wide and irrealizable.Wherein do not account for bandwidth, the message capacity in the specified frequency range is very big, the advantage that this is especially big, and then the communication of any way is all irrealizable, and the FM.AM system communication of implementing with carrier modulation technique is all more superior than the communication of any ways such as existing amplitude modulation, frequency modulation as can be known.

Undoubtedly, the communication of the FM.AM system of present technique also is applicable to and transforms popular mobile phone and radio call of the present age.In practicality, in order to distinguish with existing product, all FM.AM system new product personal handyphones and beeper number, all be in advance and add three 0, information desk is instruction with these three 0, automatically connect the FM.AM system communication equipment of native system, also can make identification signal, connect the native system communication equipment automatically by subcarrier.

According to top explanation as can be known, the various receivers of present technique are characterised in that the bandwidth frequency of passband is narrower than frequency modulating signal.This is that the various communication control processors of prior art are impossible.

Claims (5)

1, a kind of carrier modulation technique, it is characterized in that carrying out amplitude modulation with the signal of nonpolarity conversion, the amplitude modulation working procedure earlier turns to the signal of nonpolarity conversion to modulation signal with triode, again the signal voltage of nonpolarity conversion is imported the amplitude voltage that modulation circuit changes carrier wave into.

2, a kind of communication means of carrier modulation technique, it is characterized in that carrying out compatible amplitude-modulated stereo broadcast reception, transmitting terminal is controlled with electronic switch, transmit left and right acoustic channels in turn with the difference signal amplitude-modulated wave, in it and signal directly to carrier wave amplitude modulation, difference signal is earlier to subcarrier amplitude modulation, again modulated subcarrier to main carrier amplitude modulation, receiving terminal is through first enveloped detection acquisition and signal, obtains difference signal through the twice-enveloping detection, after doing the balance adjustment with difference signal, input matrix circuit reduction left and right sound track signals.

3, according to claim 1,2 described carrier modulation technique and communication meanss thereof, it is characterized in that carrying out compatible 3-D TV and broadcast reception, transmitting terminal, main image signal is directly to carrier wave amplitude modulation, sub-picture transmits the following picture signal of 1.3MHz, the sub-picture signal is called in the subcarrier of 6.5MHz earlier, again modulated subcarrier is called in main carrier, receiving terminal obtains main image signal through the first enveloped detection, obtain the sub-picture signal through the twice-enveloping detection, when watching three-dimensional program, red efferent duct cuts off the master image red signal, connects the sub-picture red signal.

4, according to claim 1,2 described carrier modulation technique and communication meanss thereof, it is characterized in that carrying out compatible high definition TV and broadcast reception, the horizontal scanning line number is increased to the twice of prior art with hold concurrently means that interlacing inserts of interlacing scan, its way, when inserting line scanning, add an amount of stable DC to field deflection coil, make line scanning move down hemistich apart from the position, transmitting terminal, the a certain narrow groove of opening at field system chronizing impulse transmits the identification signal of inserting scanning, the receiving terminal time of taking earlier separates, and takes out identification signal in the time of field system chronizing impulse, removes clutter and noise jamming with frequency selection circuit again.

5, a kind of receiver according to claim 1,2,3,4 implements communication is characterized in that the bandwidth frequency of passband is narrower than frequency modulating signal.

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