RU2155445C1 - Method for generation of single-band signal in transistor transmitter and device which implements said method - Google Patents

Abstract

FIELD: radio engineering. SUBSTANCE: method for generation of single-band signal involves generation of modulation signal, which has amplitude constituent of signal to be generated, by means of automatic amplitude control system. Then, method involves power amplification of modulation signal by means of high-efficiency power gate amplitude modulator with pulse-width modulation, and sending amplified signal through low-pass filter to collector circuit of composite transistor of high- power output synchronized self-oscillator. At the same time, synchronization signal, which contains frequency constituent of single-band signal to be generated, is sent by low-power master self- oscillator, which is controlled using frequency-control automatic regulation system directly through regulated attenuator, i.e. without power amplification. Said frequency-constituent signal is sent to sensitive synchronization circuit of same high-power synchronized self-oscillator, which synthesizes and outputs transmitter output signal. EFFECT: increased efficiency. 2 cl, 8 dwg

Description

 The invention relates to the field of radio engineering, and specifically to transmitters with single-band modulation and similar devices for generating and generating radio signals.

 It can be used in the development, construction and creation of new energy-efficient, first of all, transistor radio transmitters with single-band modulation, used in equipment of all types of radio communications, in radio stations, personal and business communications, in amateur radio equipment, in REA of multi-channel communication lines, etc. d. etc.

 Today, there are a number of methods for generating signals with single-band modulation (OM) proposed by domestic and foreign radio specialists. Here and everywhere below are meant methods for implementing single-band amplitude modulation (OAM).

 Before analyzing the analogues of the invention, it is appropriate to note that single-band modulation (OM) appeared and was first disclosed and justified as a special kind in the arsenal of methods and circuits of ordinary (two-band) amplitude modulation (AM) [1], which was primarily two times different from the last a smaller band of the frequency spectrum of the signal emitted by the antenna of the OM transmitter. Later, extremely important properties were identified and the prospects and competitiveness of transmitters with OM were substantiated.

 Consider the analogues of the invention.

The widely known filter method [21, p. 82] provides (Fig. 1) the formation of the spectrum of a conventional two-band AM signal obtained in a balanced mixer U1, the primary or reference spectrum of a single-band modulated (OM) signal at some fixed auxiliary (subcarrier intermediate, rather than operating) frequency f _pc generator G1 , complete filtering of the non-working sideband of the AM signal and the necessary filtering (suppression) of the intermediate (subcarrier) frequency f _pc . In FIG. 1 B1 - microphone.

The mentioned filtering is carried out [2] (Fig. 1) with the corresponding high-frequency (HF) band-pass filter Z1. After that, the reference OM signal (usually repeatedly) is transferred (converted) to the operating frequency f _p .

 The process of linear amplification by a multistage linear amplifier (Fig. 1, [2]) of the signal power from the OM at the operating frequency to the level that you want to have at the output, that is final in the formation of the OM transmitter necessary for radiation, is the signal in a single-band transmitter antenna.

 In the interest of increasing the linearity of the OM signal, cascade A1 and all stages of the multistage linear power amplifier A2, A3 operate in extremely low average (averaged over a long time) efficiency modes. This reduces the overall efficiency of the transmitter. Effective ways to increase the efficiency and linearity of such amplifiers have not yet been practically found.

The necessity of applying several transfers or frequency transformations when generating a working OM signal by the filter method is explained by the fact that at sharply increased high-frequency filters it is impossible to create the necessary high-frequency tunable band-pass filters (Fig. 1) Z1 with the required slope slope. That is why the intermediate (subcarrier) frequency f _{pch is} often chosen relatively low, usually from the following exemplary limits f _pch = (0.1-10) MHz.

 And this is done despite the fact that the use of a reduced intermediate subcarrier here rather than the operating frequency is one of the drawbacks of the filter method for generating an OM signal [2]. The second disadvantage is the complexity of manufacturing and the high cost of high-pass bandpass filters. The third and practically the main drawback is the need to use (as mentioned above) a multistage linear power amplifier to amplify a low-power working OM signal directly at the working frequency.

 The fact is that such multistage linear amplifiers of OM signals have, as noted above, a low average (averaged over a long time) efficiency, not exceeding 15 - 20% [3]. This value determines the industrial efficiency of the OM transmitter as a whole.

 And, finally, it is also worth noting that, since the quality and spectral purity of the output signal of the transmitter with OM directly depends on the linearity of the amplification of the OM signal in the mentioned amplifier, in this case, the requirements are to increase the quality (required spectrum purity) and improve energy efficiency, those. The industrial efficiency of the OM transmitter is mutually contradictory. Unfortunately, these contradictions have not yet been practically eliminated to date, and therefore, it remains relevant to develop a more energy-efficient way of generating an OM signal and corresponding transmitters.

 Note 1. In the claimed invention describes one of the possible ways (and an attempt is made) to eliminate the above contradictions. At the same time, it was taken into account that the filter method of generating signals from OMs from the late 50s began to be widely used in transmitting single-band technology due to the fact that during these years major successes were achieved in the development of high-quality bandpass filters using quartz and steel resonators.

 Known [4, p. 54] another, also relatively uncomplicated, phase (phase compensation) method of generating a signal with one sideband (OBP), which is not based on filtering (as in [2]), but phase compensation of one inoperative sideband (two-band AM spectrum) when the transmitter group of oscillations from a system of n channels, the oscillations of which are spaced apart in phase, is added to the transmitter’s load (adder). Most often, they are used as the simplest, three- and even two-channel systems.

The block diagram of a single-band transmitter with a two-channel system, that is, with two oscillations [4, 5], phase shifted 90 ^o relative to each other, is shown in FIG. 2. Here B1 is a microphone; A1 - microphone amplifier; U1 - low-frequency (LF) phase shifter (PV), U3 - high-frequency (HF) phase shifter; U2, U4 - balanced mixers; U5 - adder; A2 - pre-amplifier of the OM signal at the RF; A3 - power amplifier OM signal; Z1 - output oscillating system.

 It can be shown [2, 4] that at the output of adder U5 of FIG. 2 provides a signal with a lower sideband (NBP). It is obvious [2, 4] that switching the terminals of any of the LF or HF phase shifters will lead to the allocation of the output of the summing device according to the circuit of FIG. 2 not the lower, but the upper sideband (PFS).

 The advantage of the phase (phase compensation) method is the possibility of forming a spectrum of a single-band signal directly at the operating frequency, and the first significant drawback of this method [4] is the difficulty of accurately manufacturing and tuning the low-frequency band phase shifters needed here (Fig. 2) (the values of the elements of the above phase shifters should not differ from the design by more than 1% to obtain the suppression of the idle sideband by 40 dB).

 The second disadvantage of the phase method [2, 4] is the need to use a multistage linear power amplifier in the transmitter, which, as in the previous case (see the filter method [2]), sharply reduces (up to 15 - 20%) the overall industrial efficiency of the transmitter . Thus, here, as before (see above), mutually contradictory requirements remain for improving the quality of the emitted OM signal and ensuring the energy efficiency of the OM transmitter.

 Known [4, 5] is a combined phase method that combines the principles of filter [2] and phase [4, 5] methods for generating a single-band signal.

 It does not require the use of expensive high-pass bandpass filters (as opposed to the filter method) and does not require the use of low-frequency phase shifters difficult to manufacture and configure (as opposed to the phase method), but it is characterized by the first major drawback, which is that it is formed by a phase-filter method single-band signal i.e. the signal (see Fig. 3 from [2], p. 115) is characterized by reduced quality [4, 5], or rather the presence of extraneous components in it, since the spectrum of the suppressed (non-working) sideband coincides at the transmitter output with the spectrum of the useful signal (i.e. with the spectrum of the working sideband).

 The second drawback of the phase-filter method is the same, already mentioned above, the need to use a multi-stage linear power amplifier in the transmitter of a pre-formed, as a rule, low-power single-band signal, since it is usually initially generated at once at the desired operating frequency, but also has an extremely small power level.

 This also reduces the industrial efficiency of a single-band transmitter up to 15 - 20%. In addition, as is quite obvious, here, as with the two methods for generating OM signals discussed above, the conflicting requirements for improving the quality (and first of all, spectrum purity) of the emitted OM signal and ensuring the energy efficiency (high efficiency) of the OM transmitter remain unresolved.

 Creating an energy-efficient high-power linear multi-stage amplifier of OM signals for any of the single-band transmitters discussed above is technically extremely difficult. In addition, the use of electronic devices (lamps and transistors) is significantly reduced in such amplifiers. Nevertheless, the issues of increasing the energy efficiency of amplifiers of single-band oscillations (OM signals), as well as the way out of the difficulties created, have always been and remain extremely relevant now. They are in the field of view of researchers, scientists.

 At a certain stage, proposals made by L.R. Kanom [6, 7] and M.V. Verzunov [8, 9]. The methods of generating OM signals that they proposed provide for the implementation of the transmitter in the form of two paths (Fig. 4) and the exclusion of low-efficiency linear amplifiers of the power of the OM signal from single-band transmitters.

The known method (or method) of Kahn [6, 7] (Fig. 5, see p. 323 in [6]) is that it is completely formed at the desired operating frequency f _p = ω _p / 2π (in any way , for example, by filtering) a single-band low-power signal is immediately divided into two - amplitude and frequency - components [2], which are separately amplified in the respective two paths of the transmitter to the required power levels, and then fed to the input of a powerful output stage (usually a balanced power amplifier), working through the transmitter antenna output circuit. Due to this, an OM signal is synthesized in a powerful output stage at a high power level. True, in this case, the pre-terminal cascade of the path of the frequency component of the power amplifier, i.e. of the HF FM oscillation path (Figs. 4, 5), must have a power sufficient to excite a powerful output stage of the balanced amplifier, and the pre-termination stage of the low-frequency envelope amplification path, i.e. the path of the amplitude modulator, should ensure the restoration of the amplitude envelope of the OM signal synthesized in the output stage at a high power level.

 Thus, in the transmitter of FIG. 5, and more precisely in its output stage, the AM is carried out by powerful HF FM oscillations coming from the private tract.

 The advantages of the transmitter construction just discussed are related to the fact that the amplification stages of the powerful RF channel of the frequency-modulated component can work here with higher efficiency (in class C), and not with low efficiency of class A, which is usually typical for cascades of multi-stage linear amplifiers of single-band signal.

 The first drawback of the formation of an OM signal by the Kahn method (s) [6] is the complexity of the structure and circuit of such a transmitter from two paths and the need to strictly maintain the same signal delay time in the paths [10].

 The second drawback is the use of two sufficiently powerful multi-stage paths of independent separate amplification of the components of the OM signal, which, as with the other methods of OM considered above [2, 4, 5], nevertheless entails a noticeable decrease in the overall industrial efficiency of the transmitter and a sharp increase power consumption.

 The third drawback of the Kahn method [6] in transmitters is that the presence of unavoidable nonlinearities in the amplitude (low-frequency) path arising from the nonlinearity of the characteristics of the amplitude detector (Fig. 5), other path cascades, and the modulation characteristics of the cascade of the transmitter output power amplifier itself leads nonlinear distortion of the emitted output OM signal and the deterioration of its spectral purity.

 The fourth drawback of the transmitter constructed according to the Kahn type and method [6, 7] is the low maximum operating frequency (usually not higher than 20–30 MHz) if the active device of its powerful output stage operates in an advantageous energy key mode (see below) )

 The fifth drawback of the transmitter with the method of obtaining the OM signal according to [6, 7] is the mandatory use of a complicated output oscillating system in it in the interests of ensuring the required filtering of higher harmonics in the spectrum of the transmitted OM signal (in the case of the output stage in key mode).

 And, finally, it is worth noting that in some cases a high-bandwidth single-band transmitter, constructed according to the structure of [6, 7], is prone to spurious self-excitation, since the original single-band signal is generated at a sufficiently low power level, immediately at the operating frequency, and therefore, the amplifier standing after the amplifier-limiter of the frequency path (Fig. 5) of such a transmitter should always be multi-stage, have a large power gain and all its stages, including the stage of the output power amplifier, will be tuned to one the same operating frequency of the OM signal. Obviously, such a construction of the FM path of the high-frequency part of the transmitter may well negatively affect the stability of the latter.

A synthetic method for generating a single-band signal, known as the Verzunov method [8, 9], provides (Fig. 6) the formation of a low-power reference OM signal on a reduced subcarrier, i.e. intermediate frequency f _pch , which is different (see above) from the operating frequency of the transmitter, further “splitting” this low-power primary reference OM signal directly into amplitude and frequency components, creating two corresponding amplifying paths of the circuit in the transmitter and, finally, transferring the laws amplitude and frequency modulation (FM) from the reference low-power inoperative OM signal to a powerful OM oscillation, i.e. synthesizing an OM signal in an output balanced amplifier stage having the desired operating frequency and providing the required output power of the emitted OM signal in the transmitter antenna.

 The block diagram of the transmitter, which uses the synthetic method for generating the OM signal shown in FIG. 6, borrowed from [8, see p. 69]. It contains a driver of a reference single-band modulated signal (OM signal), operating at an intermediate (non-working) frequency, connected by its output to the inputs of the amplitude and frequency paths, elements and nodes of these paths, a synthesizing device made in the form of an output powerful amplifier operating on an antenna in which the combination-synthesis (actually, multiplication) of sufficiently powerful output signals of the end stages of the amplitude and frequency paths, respectively, is carried out when they are input to the power output amplifier operating as a balanced mixer, the necessary output circuit, i.e. oscillatory system of the transmitter, as well as auxiliary elements for unlocking the cascade of a powerful output amplifier, i.e. synthesizing device of the transmitter, when the reference OM signal appears.

 In the transmitter of FIG. 6 of [8, see fig. 11.18, p. 69] the frequency path consists of an amplitude limiter, a discriminator - a frequency detector, a reactive element, a low-power master oscillator, tuned to the operating frequency of the transmitter, and its self-generating frequency is automatically modulated (controlled) by the voltage from the frequency detector, and, finally, a preliminary RF amplifier power, and the amplitude path (the path of the envelope of the OM signal) contains a linear amplitude detector and usually a fairly powerful modulator - a linear DC amplifier (amplifies l envelope).

 The synthetic method [8, 9] for generating a single-band signal also has several disadvantages.

 The first of them is associated with the complex construction of such a transmitter, and the second is that it is difficult, but it is necessary to ensure high accuracy and linearity in the amplitude and frequency paths, otherwise the laws of changing the amplitude and frequency of the output synthesized OM signal generated at the operating frequency in the output synthesizer in the circuit of FIG. 6 and delivered through the transmitter antenna output circuit will differ from the laws of changing the amplitude and frequency of the initially generated (at an intermediate idle frequency) reference single-band signal, i.e. nonlinear distortion occurs in the output transmitted signal of the transmitter OM.

 The third disadvantage of the transmitter [8, 9] is related to the fact that the linear DC amplifier used in its amplitude path at high radiated power can be quite powerful with low efficiency, which significantly worsens the industrial efficiency of the transmitter.

 The fourth drawback is that the author of a synthetic method for generating an OM signal according to [8, 9] proposes to use an output stage as a synthesizing device, made according to the scheme of a balanced RF power amplifier, the efficiency of which is low for a wide range of amplified signal voltages, which is also low reduces the industrial efficiency of such an OM transmitter.

 And finally, the fifth drawback of the method [8, 9] can also be attributed to the difficulty, but it is necessary to establish a slightly different delay time in the circuitry of sharply different amplitude and frequency paths, otherwise nonlinear distortions may occur in the synthetically generated OM signal, since the transmitters [6-10] nothing is envisaged to eradicate such distortions.

 It can be seen that in transmitters with single-band modulation carried out both according to the Kahn method and the synthetic method of Verzunov, instead of a multistage linear (energy-low efficient) amplifier of the OM signal, it is proposed to make two parallel and sufficiently powerful paths. But they have serious and important flaws.

 It was later shown [11] that the final stage of the amplifier of the FM signal of the frequency channel of the transmitters according to the type of the Kahn method and the Verzunov method is advantageously put in the key mode, which provides a slight increase in the overall efficiency of such transmitters. In the interests of this, it is possible to apply the key mode in the output stage itself [11], as well as provide voltage amplification of the amplitude envelope of the OM signal and its restoration in the latter due to the use of a PWM modulator [11] in the terminal stage of the transmitter amplitude path. However, all these solutions complicate the already complex transmitter circuits from [6-10]. Moreover, in these cases, it is not possible to effectively solve the problem of improving the purity of the spectrum of the transmitted OM signal and to get rid of a number of important device shortcomings noted above [6–10].

 The closest analogue (that is, the technical solution that we have chosen as a prototype) of the invention is a single-band transmitter with the formation of a single-band-modulated (OM) signal in it in a synthetic way and the use of two closed systems [12], which are extremely useful for such transmitters [12] autoregulation (ATS), one of which is implemented by the amplitude component (more precisely, by the envelope) of the OM signal - by its frequency component, and the feedback signal for these two closed ATS is removed from the antenna jack input. There is a third (local) auxiliary ATS in the transmitter [12]. It is built into its channel of the amplitude component (cascade of the differential amplifier) and serves to automatically maintain the peak level of the OM signal.

 Briefly describe a single-band transmitter "Polar loop SSB transmitter", constructed according to [12].

 A single-band transmitter constructed according to [12] consists (Fig. 7) of: a shaper of a reference single-band signal with a filter method of receiving it on an auxiliary idle, i.e. intermediate frequency; a frequency converter excited by a feedback signal taken from the input (clamp) of the antenna (i.e., an OM signal generated by the transmitter and emitted by the antenna), which is transferred (for automatic control systems to operate) to the same auxiliary intermediate frequency at which the reference driver operates OM signal; two synchronous detectors (each of which contains a mixing detector and an amplitude limiter), dividing the OM signals arriving at them into their amplitude and frequency components and directing the latter along the corresponding (amplitude and frequency) paths; the differential amplifier of the amplitude channel, which generates and amplifies the voltage of the error signal in amplitude, which controls the amplitude of the FM high-frequency oscillations in the amplitude modulated end-stage cascade of the transmitter generator path, synthesizing the OM signal at the operating frequency in it (and therefore the envelope voltage is applied to one input of the differential amplifier from the chains of the reference OM signal, and on the other, the voltage proportional to the envelope of the actual OM signal emitted by the antenna and from the SAR chain in amplitude); the cascade of the output power amplifier of the previously synthesized working single-band signal coming from the pre-terminal stage, as well as the output oscillatory system with the transmitter antenna.

 The elements and nodes of the second closed-loop SAR transmitter in frequency, made according to the PLL type, are (Fig. 7) a phase detector, a filter at its output, and a VCO, i.e. a voltage-controlled oscillator, and the frequency of the VCO is controlled by the phase error output signal from the output of the just-mentioned phase detector, passed through a filter (low-pass filter). The input signals (there are two of them) for the just mentioned phase detector (path of the frequency component of the transmitter) are signals taken from the amplitude limiters that are part of the above two synchronous detectors.

 And finally, the elements of the third ATS in the single-band prototype transmitter proposed in [12], which is the local system for automatically maintaining the peak signal level, are the high-pass filter (Fig. 7), to which the ATS initially receives an output signal the cascade of the differential amplifier of the amplitude path, the amplifier following the HPF, and the peak level maintenance circuit itself (see block 1 in Fig. 7), directly controlled by the amplifier just mentioned.

 The signal generated by the third ATS from the output of the peak level maintenance circuit enters the bias circuit of the differential amplifier (the first ATS in amplitude), automatically adjusting its gain. The specific task of the third SAR transmitter is to always reduce the transmission coefficient in the first SAR in amplitude, acting on its differential amplifier (which is an error signal amplifier) when the signal at the output of this amplifier exceeds a certain threshold value.

 All three ATS used in the transmitter according to [12], in a complex, solve the problems of improving quality indicators and characteristics and, first of all, reduce non-linear distortions and increase the spectral purity (spectrum purity) of single-band modulated signals emitted by the transmitter.

 However, the aforementioned ATS practically do not in any way improve the energy performance, and therefore, the industrial (average over a long time) efficiency of such an OM transmitter from [12] also remains significantly reduced and does not exceed the values characteristic of transmitters with OM signals from [2-11 ].

 Based on the foregoing, it can be pointed out that the main disadvantage of the transmitter, which is the closest analogue of the invention, constructed using the Polar loop transmitter system [12] with a synthetic method for generating a single-band signal, is that it, like other analogs, has a low industrial efficiency, which is associated with the conventional classical construction of its radio frequency part, i.e. radio frequency or generator path.

 Specifically, the low industrial efficiency of the transmitter is explained not only by the fact that it is built according to the classical multi-stage block diagram of the radio frequency part with energy-disadvantageous modes of operation of its powerful stages, but also by receiving (synthesizing) the OM signal not in the output, but in the end-stage cascade, which required the use energetically unfavorable linear amplification mode of the OM signal in the most powerful output stage. This version of the synthetic method for generating an OM signal cannot be considered effective, since with it, as before, the efficiency of the most powerful cascade and the overall industrial efficiency of the OM transmitter are reduced.

 Considering and solving the issues of increasing the overall efficiency of the OM transmitter, it should also be borne in mind that the efficiency of each individual cascade of the radio-frequency (or generator) part (path) of the transmitter in the amplification mode of signals with a large dynamic range is energetically disadvantageous. Therefore, taking into account the totality of the foregoing, it becomes quite obvious the feasibility of using non-classical construction of their structural circuits in modern transistor single-band transmitters with an extremely minimal number of cascades in their radio-frequency or generator paths.

 The solution of these issues is achieved by the unusual implementation of the process of forming an OM signal by a synthetic method in a transistor transmitter, the one-stage block diagram of the radio-frequency generator part of which is built on the basis of an energy-efficient powerful transistor synchronized oscillator (SAG) made using the last active device in the form, for example, of a hybrid a composite transistor (GTS) with a mode transistor and an additional mode source, and for provided I synthetic method for the formation of a powerful signal OM unusual original output synthesizing apparatus, i.e. In the original cascade of the synchronized oscillator on the GTS, collector amplitude modulation is used using an energetically beneficial PWM-based key modulator.

 The possibility of implementing a new method of generating an OM signal, as well as a new construction of an OM transmitter, is due to the fact that synchronized oscillators on composite transistors and, above all, on dual GTS (GTS2) of different power [13] can successfully perform the functions of output powerful oscillator amplifiers power (AUM) of radio frequency oscillations in the most diverse, including single-band, transistor radio transmitters, i.e. effectively replace the GVV in the role of RF power amplifiers. Experimental studies of the prototype transistor HF single-band transmitter created by the authors with the claimed new synthetic method for the implementation of OM (and the single-stage RF part of the transmitter) confirmed the statements made just above.

 The objective of the invention is to provide a significant increase in the overall industrial efficiency of the transmitter while maintaining both the simplicity of its circuitry and high quality indicators and the purity of the spectrum of the transmitted signal.

 This problem is solved by implementing a method of generating a single-band signal in a transistor transmitter, which consists in generating a reference single-band signal at an intermediate frequency and simultaneously removing a feedback signal from the antenna output of the transmitter and transferring it to the same intermediate frequency, then based on these signals they form error signals in amplitude and phase, then the amplitude tracking error signal is converted into a signal containing an envelope, and the phase tracking error signal is converted signal containing a frequency component generated sideband signal, characterized in that the synchronized oscillator output transistor simultaneously on the composite amplitude modulated signal containing the envelope, and is synchronized by the signal frequency, comprising frequency component formed by a single-sideband signal.

 To implement the method, a device (transmitter) has been developed, the prototype of which is the device (transmitter) "Polar loop SSB transmitter" [12], FIG. 7, containing a series-connected microphone, a driver of a single-band reference signal and a first synchronous detector, as well as a series-connected frequency converter and a second synchronous detector, the output 1 of the first synchronous detector is connected to the direct input of the differential amplifier, and the output 1 of the second synchronous detector is connected to the inverse input of this the differential amplifier, the outputs 2 of the first and second synchronous detectors are connected to the inputs of the phase detector, the output of the phase detector through the filter is connected to the control input of the voltage-controlled generator, the output of which is connected through the buffer cascade to the input of the amplitude-modulated cascade, the other input of this cascade is connected to the output of the differential amplifier, the output of the differential amplifier is also connected through a high-pass filter, an amplifier, and a peak level circuit connected to the bias circuit of this differential amplifier, the output of the amplitude-modulated cascade is connected to a multi-stage power amplifier B fluctuations which vibrational system via the output (LPF) connected to the antenna and transmitter to the input of the frequency converter.

 To implement the method, a device has been developed that contains a series-connected microphone 1, a driver of a single-band reference signal 2 and a first synchronous detector 3, as well as a series-connected frequency converter 4 and a second synchronous detector 5, the output 1 of the first synchronous detector 3 is connected to the direct input of the differential amplifier 6 and the output 1 of the second synchronous detector 5 is connected to the inverse input of this differential amplifier 6, the output of which is connected through the circuit for maintaining the peak level 7 n to the control circuit of the same differential amplifier 6, the outputs 2 of the first and second synchronous detectors 3 and 5 are connected to the inputs of the phase detector 8, the output of the phase detector 3 through the filter 9 is connected to the control input of the generator controlled by voltage 10, characterized in that the differential output amplifier 6 is connected to the input of the key amplitude modulator 11, the output of which through the low-pass filter - corrector 12 is connected to the collector circuit of the output synchronized oscillator on a composite transistor 13 and to the control circuit of the adjustable attenuator 14, and the input of the generator controlled by voltage 10, through the adjustable attenuator 14, is connected to the sync input of the output synchronized oscillator on the composite transistor 13, the output of which through the output oscillating system 15 is connected to the antenna 16 of the transmitter of the sensor and the input of the frequency converter 4.

 The transmitter, which implements the inventive method of forming a single-band signal, operates as follows.

 An electric low-frequency signal appearing at the output of the microphone 1 is supplied to a typical single-band signal shaper 2, made by the filter method, the output of which appears a single-band reference (OM) signal, the value of the suppressed carrier frequency of which is equal to the intermediate frequency used in this transmitter. The generated reference OM signal is fed to the input of the first synchronous detector 3. At the output 1 of the first synchronous detector 3, a signal is generated whose value is proportional to the instantaneous value of the envelope of the reference single-band signal, and at its output 2 an extremely limited (i.e., having a constant amplitude) signal is generated whose instantaneous frequency is equal to the instantaneous frequency of the reference OM signal. Thus, information (in the form of signals) about its instantaneous envelope and instantaneous frequency is extracted from the spectrum of a complex reference single-band modulated oscillation.

 At the same time, the output OM signal of the transmitter generated at the operating frequency taken from the antenna clamp (feedback signal) is fed to the input of the frequency converter 4, in which it is transferred from the operating frequency to the intermediate frequency (on which the above reference OM signal is generated in the driver 2 transmitters), after which it is fed to the input of the synchronous detector 5, which works similarly to the synchronous detector 3 (see above).

 Thus, information on the instantaneous amplitude and instantaneous frequency is extracted from the emitted OM signal generated at the operating frequency at the output of the transmitter and entering the antenna, as well as from the primary reference OM signal.

 Note 2. In the presence of distortions in the transmitter (i.e., the output signal of the synthesized device), information on the instantaneous frequency and envelope of the amplitude of the signal generated at the antenna output will differ, respectively, from information on the instantaneous frequency and envelope of the amplitude of the primary reference OM signal.

 The signal from the output 1 of the first synchronous detector 3 is fed to the non-inverting input of the differential amplifier 6; the signal from the output 1 of the second synchronous detector 5 is fed to the inverting input of the same differential amplifier 6. Differential amplifier 6 isolates and amplifies the difference between the values of the signals at its inputs, i.e. amplitude tracking error signal. If there appears a deviation of the instantaneous amplitude of the OM signal, taken through the OS circuit from the antenna output of the transmitter, from the value determined by the instantaneous amplitude of the reference OM signal, the signal of the tracking error in amplitude at the output of the differential amplifier 6 changes accordingly, which, in turn, leads to a change in the envelope of the amplitude of the output signal of the transmitter (which will be discussed in more detail below). Thus, the transmitter is covered by a closed-loop automatic control system (CAP) in amplitude based on the OS, providing an exact correspondence of the instantaneous amplitudes of the reference and output OM signals.

 The output signal of the differential amplifier 6 is fed to the input of a powerful key modulator 11 using the principle of pulse width modulation. The output voltage of the key modulator 11 has the form of a sequence of rectangular pulses with a constant amplitude and clock frequency, and the duration ("width") of these pulses depends on the magnitude of the control signal from the differential amplifier 6. With an increase in the value of this signal, the pulse duration increases, and accordingly constant component in the spectrum of the pulse sequence (and vice versa).

 The constant component of the output voltage of the key modulator 11 is isolated by a low-pass filter (low-pass filter) 12 and fed to the power circuit of the output electrode (collector) of the active device of the synchronized oscillator 13, made on a composite transistor (i.e., the AUM cascade on the GTS2), which gives the ability to control the amplitude of the high-frequency oscillations at the output of this synchronized oscillator 13, used in this transmitter as a synthesizing device.

 An LPF corrector 12 is necessary not only to smooth out the ripple of the output current of the key modulator 11 (filtering function), but also to ensure stability in a closed autoregulation system (ATS) in amplitude, which is achieved by a special circuit design of this LPF corrector.

 The signals from the outputs 2 of the first and second synchronous detectors 3 and 5 are fed to the inputs of the phase detector 8. The phase detector 8 emits a phase tracking error signal, which through the filter 9 is fed to the frequency control input of the oscillator (VCO) 10. The output signal of the oscillator (VCO) 10, which already has a working frequency, is fed through an adjustable attenuator 14 to the synchronization input of a powerful synchronized oscillator 13, which is the output stage of the transmitter, i.e. a synthesizing device in the form of AUM. Thus, a transmitter with an OM signal is covered by a closed autoregulation system (ATS) and according to the working frequency of the output signal, made by the PLL type, which causes the instantaneous operating frequency of the output signal of the OM transmitter to deviate from its value of the suppressed carrier frequency by the same amount by which the instantaneous intermediate frequency of the reference signal deviates from its value of the suppressed carrier frequency.

 The adjustable attenuator 14 reduces the level of the clock signal supplied to the synchro input of the powerful output synchronized oscillator 13 while reducing the voltage supplying the output electrode of the active device (collector GST2) of the powerful AUM 13.

 The output signal of the synchronized oscillator 13, i.e. A powerful synthesizing device of the transmitter in the form of AUM, is fed through the output oscillating system 15 to the antenna socket (clip), where the antenna 16 is connected. The same signal is also fed to the input of the frequency converter 4 operating in the OS circuit used in the transmitter. Antenna 16 emits a single-band signal generated by the transmitter.

It is worth emphasizing that the main features of the proposed method and the transmitter based on it are:
- the formation of a working OM signal emitted by the transmitter, synthesized in the original synthesizing device, which is not a classical power amplifier (balanced cascade of a power amplifier, cascade of a generator with external excitation), but a new cascade of a power amplifier’s oscillator (AUM), based on a powerful synchronized oscillator ( SAG) on a complex active device (SAP), for example, on a powerful dual hybrid composite transistor (GST2) with a mode transistor in its structure or another gene rotary composite transistor (CT) [13];
- the use of collector amplitude modulation of the SAG (i.e., the output AUM) as an energetically favorable and technically suitable collector amplitude modulation;
- introducing the RF RF component of the generated OM signal into the output synthesizing device of the SAG (AUM) type as a low-power clock signal directly taken from the output of the low-power master oscillator (VCO), i.e., without additional gain in power (for example, through low-frequency attenuator envelope signal), for which such a clock signal is supplied to special sensitive synchronization circuits provided for in the SAG performed according to the AUM scheme [13].

 A comparative analysis and comparison with the closest analogue (prototype) of the invention shows that the technical solution claimed here is distinguished by the presence of a new synthesizer for the first time used (for synthesizing a working OM signal in single-band transmitters) in the form of a powerful self-generating power amplifier (AUM) based on a powerful synchronized oscillator (SAG), for example on the original dual hybrid composite transistor (GST2) with a mode transistor and an additional mode power supply [13], as well as the practical absence of a powerful RF amplification path for the RF component, since the latter is supplied to the SAG (AUM) synchro-in as a low-power sync signal, for example, through the attenuator cascade from the originally used master oscillator (VCO) of the PLL transmitter system . VCO in the path of the HF FM component of the OM signal without subsequent amplifiers of the HF FM signal is used in the technique of single-band transmitters for the first time.

 You can talk about other differences of the claimed technical solution from the closest analogue (prototype) and other analogues (see below), but this is already enough to conclude that the claimed technical solution meets the criteria of the invention of "novelty."

 To disclose the inventive step, we continue the conversation about other differences of the invention. So, in contrast to the closest analogue (prototype) of the present invention, the low-frequency component (amplitude envelope) of the reference OM signal comes from the output of the differential amplifier operating in the OS circuit by amplitude, through an amplitude modulator made (in contrast to the closest analogue prototype) based on a pulse-width modulated (PWM) cascade with an LPF corrector, directly into the output electrode circuit (high-power collector circuit) of the active output SAG (AUM) device and performs the necessary s energetically favorable amplitude collector [1] modulation of the latter, that, for the transistor stage powerful SAG AUM and on their basis is proposed and used in the art (and technical literature) again first.

 The present invention is interesting in that when implementing a new method for generating an output, i.e., a single-band transmitter emitted by an antenna, working OM signal, a cascade-attenuator (active attenuator) controlled by the modulating collector voltage is used in the synchronization and passage circuit of the RF frequency component, and in the SAG ( AUM) is a special capacitive divider that provides an increase in the linearity of the characteristics of the collector amplitude modulation of AUM, synthesis of a working OM signal and stable operation of the SAG only when required ln the presence (supply to the GST2 SAG 32) of a clock signal containing an HF FM component. It is in this mode that the output working OM signal is synthesized at a high power level and high linearity of the signals emitted by the transmitter is ensured (see below).

 The introduction into the OM transmitter of the new blocks and elements mentioned above, new approaches to organizing and conducting the “technological implementation operations” of all the components for performing the synthetic method led to the appearance in the transmitter of a completely new functioning synthesizing device (in the form of AUM on SAG), new connections, new circuits, new paths of passage, both of the low-frequency envelope of the reference OM signal and of its HF FM component. These new solutions and connections could not and do not exist in analogues in general and in the closest analogue, in particular. It is appropriate to say once again that a single-band transistor transmitter as an object where the proposed method for generating a powerful output OM signal is implemented is distinguished by an original and simple structural scheme.

 Thus, the presence of original solutions, new blocks, cascades, elements, nodes, their connections with each other and with other elements, the appearance of new properties, new paths for the RF and LF components of the reference OM signal during the formation of a powerful output working OM signal in a synthetic way allows to conclude that the claimed technical solution meets the criteria of the invention "inventive step".

 And, finally, the compliance of the claimed technical solution with the criterion of the invention "industrial applicability", that is, the performance of the proposed new synthetic method in the original transistor single-band radiotelephone transmitters, is due to the following circumstances.

 Firstly, in the transmitter, the output stage of the AUM (based on the SAG) is made according to a promising operable self-generating capacitive three-point using the Clapp circuit and is covered by the necessary positive feedback (POS), which provides soft self-excitation and stationary operation of the SAG (AUM) [13] upon receipt on the SAG (and in the AUM) a synchronizing (rather than exciting) signal that carries an RF FM component with a value corresponding to the level of the LF envelope of the reference OM signal. This provides an adjustable attenuator (active type) in the SAG synchronization circuit (AUM).

 Secondly, the AUM provides all the necessary conditions for the operation of its complex active device (SAP) with the arrival of the clock signal, since all the electrodes of the single transistors of the structure of the GST2 type SAPS are supplied with the supply voltage and bias corresponding to them [13], and the mode transistor is powered by an additional (separate) operating source, from the last filed and the offset to this transistor. In the device, i.e. the transmitter to implement the proposed new method for generating a working OM signal at a high output power level, the necessary operating modes are created and there are all necessary elements (i.e., three-point circuit details, elements of the output matching circuit, a PWM-based modulator, low-pass corrector, power supply circuit elements and offsets specifying the AUM DC mode of operation and the operation of the transmitter as a whole).

 Thirdly, low-current transmitter circuits (driver of the reference OM signal 2, synchronous detectors 3 and 5, frequency converter 4 of the spectrum of the output OM signal, differential amplifier 6, cascades and elements of the PLL system, VCO-synchronizer, and other nodes) are functional and their functioning practically does not need special additional explanations.

 It is no coincidence that for the first time one of the prototypes of the proposed technical solution (method and device for it) was created experimentally and has just been tested above, i.e., the proposed circuit design, it has successfully passed laboratory tests and verified operation in a real environment, i.e. in the communication channel.

 The presence in the claimed invention of novelty, the necessary inventive step and the possibility of industrial application indicate sufficient development of the proposed solution. Moreover, in single-band transmitters with the claimed technical solution, conditions have been created to ensure high frequency stability during operation, sufficiently high quality indicators, primarily the necessary linearity, good purity of emitted oscillations and increased average industrial efficiency.

 We note once again that the proposed technical solution uses noticeably simplified structural and circuit diagrams of the original transistor radiotelephone transmitters. They also propose to use the method of forming single-band signals.

 The original devices (transmitters) and the proposed method for generating a working output OM signal of the corresponding power, determined by the power of the output AUM, are technically clear, the processes occurring in them during operation are physically understandable and explainable, practically feasible and experimentally verified.

Below are presented:
in FIG. 1 is a structural diagram of a single-band transmitter with a filter method for generating a single-band signal;
in FIG. 2 is a structural diagram of a single-band transmitter with a phase (phase compensation) method for generating a single-band signal;
in FIG. 3 is a structural diagram for explaining the principle of a phase-filter method for generating a single-band signal;
in FIG. 4 is a construction diagram of a single-band transmitter with separate power amplification of two components of a single-band signal;
in FIG. 5 is a structural diagram of a single-band transmitter constructed by the Kahn method (method);
in FIG. 6 is a structural diagram of a single-band transmitter with a synthetic method for generating a single-band signal (Verzunov method);
in FIG. 7 is a structural diagram of a single-band transmitter adopted (by the method of generating a single-band signal in it) as the closest analogue of the invention;
in FIG. 8 is a structural diagram of a single-band transmitter with the inventive method of forming a single-band modulated (OM) signal.

Information Sources Used
1. Sudakov Yu. I. Amplitude modulation and collector self-modulation of transistor generators (Methods, theory, calculation). - M.: Energy, 1969, 392 p.

 2. Verzunov M.V. Single-band modulation in radio communications. - M.: Military Publishing, 1972, 296 p.

 3. Artym A. D. et al. Improving the efficiency of powerful radio transmitting devices. / Ed. Artyma A.D. - M .: Radio and communications, 1987, 176 p.

 4. Polyakov V.T. Radio amateurs about the technique of direct conversion. - M .: Patriot, 1990, 264 p.

 5. Radio transmitting devices. / Ed. Zeitlenka G.A. - M.: Communication, 1969, 543 p.

 6. Terentyev B.P. and other radio transmitting devices. / Ed. Terentyeva B.P. - M .: Communication, 1972, 456 p.

 7. Kang L.R. Compatible single-band radio system. IRE, Nat Conxent Rec., N 5, N 7, 1957.

 8. Verzunov M.V., Lobanov I.V., Semenov A.M. Single band modulation. - M .: Svyazizdat, 1962, 300 p.

 9. Aut. St. N 109137 (USSR). Method of single-band modulation of radiotelephone transmitters. / Verzunov M.V. Publ. 1957. Bull. N 10.

 10. Novikov G.V., Tenyakshev A.M. Evaluation of distortion in an amplifier with separate amplification of the components of a single-band signal. // Radio engineering, 1978, t. 33, N 6, p. 33-38.

 11. Shahgildyan V.V. et al. Design of radio transmitting devices. / Ed. Shahgildyan V.V. 3rd ed., Rev. and add. - M.: Radio and Communications, 1993, 512 p.

 12. US patent N 4481672. The transmitter with a closed feedback circuit. MKI 3 H 04 B 1/04. Publication 84.11.06, T 1048 N 1 (VNIIIPI 127-14-85 OFFICIAL GAZETTE).

 13. Autost. N 1748252 (USSR). Synchronized auto generator. / Sudakov Yu.I., Petrov E.A. Priority from 11.22.89. Publ. 07/15/92. Bull. N 26.

Claims (2)

 1. A method of generating a single-band signal in a transistor transmitter, which consists in generating a single-band reference signal at an intermediate frequency and simultaneously removing a feedback signal from the transmitter antenna output and transferring it to the same intermediate frequency, then, based on these signals, error signals are generated by amplitude and phase, then the tracking error signal in amplitude is converted into a signal containing the envelope, and the phase tracking error signal is converted into a signal containing the frequency component iruemogo single-sideband signal, characterized in that the synchronized oscillator output transistor simultaneously on the composite amplitude modulated signal containing the envelope, and is synchronized frequency signal having a frequency component formed by a single-sideband signal.  2. A single-band signal transmitter containing a microphone in series, a single-band reference signal generator and a first synchronous detector, as well as a frequency converter and a second synchronous detector connected in series, the first output of the first and second synchronous detector is designed to generate a signal on it, the magnitude of which is proportional to the instantaneous value the envelope of the single-band signal input to the synchronous detector input, and the second output - to form extremely amplitude-constant signal whose instantaneous frequency is equal to the instantaneous frequency of a single-band signal input to the synchronous detector input, the first output of the first synchronous detector is connected to the direct input of the differential amplifier, and the first output of the second synchronous detector is connected to the inverse output of this differential amplifier, the output of which is through the support circuit peak level connected to the control circuit of the same differential amplifier, the second outputs of the first and second synchronous detector in connected to the inputs of the phase detector, the output of the phase detector through the filter is connected to the control input of the voltage-controlled generator, characterized in that the output of the differential amplifier is connected to the input of the key amplitude modulator, the output of which through the low-pass filter is connected to the collector circuit of the output synchronized oscillator on a composite transistor and to the control circuit of an adjustable attenuator, and the output of the generator controlled by voltage through an adjustable attenuator is connected n synchronized to the clock output of the oscillator on the composite transistor, the output of which through the output oscillating system is connected to the antenna transmitter and entry of the frequency converter.

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