JP2006042227A - Automatic pulse waveform shaping system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce noise caused by electrical interference between differential signal lines, to match characteristic impedance between the differential signal lines, and to reduce a reflection loss and a transmission loss of a high frequency signal, in order to solve problems wherein waveform shaping of an exciting signal is required for using a non-linear power amplifier in large power transmission, detailed waveform shaping corresponding to respective characteristics is also required because of characteristic variations of the power amplifier, exciting signal waveform variations and the others, and much labor is therefore required. <P>SOLUTION: In a modulator 2, an exciting signal is outputted as a transmission output signal via power amplifiers 5<SB>1</SB>-5<SB>n</SB>, a power synthesizer 6 and a directional coupler 7 after shaping its waveform with a modulation signal from a waveform control circuit 9. The transmission output signal is monitored by a detector 8, its monitor signal waveform is compared with a reference signal waveform by a comparator 12 to obtain an error, and the error is stored in a correction signal generator 14 and then added to a modulation signal from a modulation signal generator 15 by an adder 16. Thus, a modulation signal waveform wherein said error is corrected into previous modulation signal waveform, is obtained from the adder 16. The next exciting signal is modulated by the next modulation signal to which said correction is applied, and operation of pulse waveform shaping is repeated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an automatic pulse waveform shaping method, and more particularly to an automatic pulse waveform shaping method for shaping a pulse, which is a transmission signal, in a pulse transmitter such as a navigation aid device and a radar device having a transmitter that generates a large amount of power.

  Pulse transmitters such as navigation aids and radar devices need to generate large power signals, and those using electron tubes have been widely used. However, in recent years, with the development of power semiconductor devices, pulse transmitters have been put into practical use that combine many of these to obtain a high power transmission output.

FIG. 8 shows a block diagram of an example of the above-described pulse transmitter to which the conventional automatic pulse waveform shaping method is applied. In the figure, the continuous wave output from the signal generator 1 is pulse-modulated by a pulse modulator 20 to become an excitation signal. The excitation signal is amplified by the preamplifier 3 to the input level of the power amplifiers 5 _{1 to} 5 _{n which} are _n power semiconductor devices in the subsequent stage (n is an integer of 2 or more), and then distributed by the power distributor 4. And input to the power amplifiers 5 _{1 to} 5 _n in parallel.

The excitation signals extracted by power amplification separately by each of the power amplifiers 5 _{1 to} 5 _n are combined by the power combiner 6. Thus, in the case of a solidified transmitter, since the output power of one power semiconductor device (power amplifier) is small, a large number (n in FIG. 8) of power semiconductor devices are operated in parallel, and their outputs are A desired output power is obtained by combining the power with the power combiner 6.

  The excitation signal output from the power combiner 6 is shaped into a desired transmission output signal waveform by a method such as filtering a predetermined frequency component by the subsequent filter or pulse shaper 21 and output. Here, there is a well-known method of reducing unnecessary radiation components by smoothing the rising and falling of a rectangular wave or by amplitude-modulating with a Gaussian waveform or the like to suppress the spread of the signal spectrum.

  Conventionally, the pulse modulation signal from the pulse modulator is supplied to the correction unit, and based on the error signal generated by this, a continuous delay is introduced at the pulse edge of the pulse modulation signal to retime the pulse modulation signal. There is known a method of performing control such that the step of retiming has a compensation effect on the power amplification signal from the switching power amplification stage of the pulse modulation signal (see, for example, Patent Document 1). According to the method described in Patent Document 1, the pulse waveform is shaped by pulse edge delay.

Japanese Patent No. 3346581

  In the solidified transmitter shown in FIG. 8 described above, when the power amplifier is a linear circuit, it is easy to shape the excitation signal into a desired transmission output signal waveform by shaping the waveform of the excitation signal. However, since the power amplifier is generally a non-linear circuit such as a class C operation in order to increase efficiency, the waveform of the excitation signal is distorted and deformed. For this reason, when pulse shaping is performed after the power amplifier, the filter or pulse shaper 21 is required at the final stage of the transmitter as described above.

  However, the loss of these components directly leads to a decrease in transmission power, and the power to be handled is very large, so special components are required. Further, in order to avoid this, when shaping the excitation signal into a desired transmission output signal waveform by shaping the waveform, detailed waveform shaping is required because of a nonlinear power amplifier of class C operation.

Conventionally, it is necessary to perform detailed waveform shaping in accordance with the characteristics of the power amplifiers (power semiconductor devices) 5 _{1 to} 5 _n , fluctuations in the excitation signal waveform, frequency characteristics, and the like. Labor is required.

  On the other hand, the method described in Patent Document 1 is to re-timing the pulse edge of the pulse modulation signal with a continuous delay in order to correct non-linearity introduced during power amplification (power amplification). Detailed waveform shaping is required.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an automatic pulse waveform shaping method that can easily shape a pulse waveform of a transmission signal.

  In order to achieve the above object, an automatic pulse waveform shaping system according to a first aspect of the invention comprises a modulation means for shaping a waveform by pulse-modulating an excitation signal with a modulated signal of a pulse train synchronized with transmission timing, and a waveform by the modulation means. Power amplification means for power-amplifying the shaped and outputted excitation signal; and branching means for branching the excitation signal power-amplified by the power amplification means into two, one of which is output as a transmission output signal in synchronization with the transmission timing; A detection means for detecting the other transmission output signal branched by the branching means and outputting a monitor signal, and a reference signal generator, and a waveform of the reference signal output from the reference signal generator and the detection means The modulation signal output at the previous transmission timing is corrected with the error / correction signal corresponding to the error obtained by comparing the waveform of the monitor signal output from the , And having a waveform control means for outputting a modulated signal after the correction to the modulation means at the next transmission timing.

  In the present invention, when the excitation signal is waveform-shaped with the modulation signal, and the excitation signal after waveform shaping is subjected to power amplification and transmission output, the transmission output signal is monitored, and the monitor signal waveform is compared with the reference signal waveform. The error is corrected, the error is corrected to the previous modulation signal waveform to obtain the next modulation signal waveform, the next excitation signal is modulated with the corrected next modulation signal, and the operation of shaping the pulse waveform is repeated. Therefore, the transmission output signal waveform converges to the reference signal waveform, and a transmission output signal waveform similar to the reference signal waveform is automatically obtained. Further, any transmission output signal waveform can be handled by selecting a desired reference signal waveform. For example, when a Gaussian waveform is selected as the reference signal waveform, the transmission output signal waveform becomes a Gaussian waveform, and the spread of the spectrum of the signal can be suppressed, and unnecessary radiation components can be reduced.

  In order to achieve the above object, the automatic pulse waveform shaping system of the second invention is characterized in that the waveform control means of the first invention includes a reference signal generator and a waveform of a reference signal output from the reference signal generator. Is compared with the waveform of the monitor signal and outputs an error / correction signal, an error / correction signal generator that stores the error / correction signal output from the comparator, and output at the previous transmission timing The modulation signal generator for storing the modulated signal, the error / correction signal at the previous transmission timing output from the error / correction signal generator at the next transmission timing, and the previous output from the modulation signal generator. Addition means for adding the modulation signal at the transmission timing and outputting the result to the modulation means as a modulated signal after correction at the next transmission timing.

  In order to achieve the above object, the automatic pulse waveform shaping system according to the third aspect of the present invention has a burst pulse composed of k pulses (where k is an integer of 2 or more) in which the excitation signal is synchronized with the transmission timing. Modulating means for shaping the waveform by performing pulse modulation with the modulation signal synthesized in series, power amplifying means for amplifying the power of the excitation signal output after waveform shaping by the modulating means, and power amplification by the power amplifying means The excited excitation signal is branched into two, one of which is output as a transmission output signal in synchronization with the transmission timing of the burst pulse, and the other transmission output signal branched by the branching means is detected and a monitor signal is output. The detection means and the reference signal generator are included, the waveform of the reference signal output from the reference signal generator, and the burst pulse output from the detection means According to the error obtained by comparing the waveform of the monitor signal of the transmission output signal synchronized with the jth pulse (where j is an arbitrary value from 1 to k) of the pulses. The error / correction signal is used to correct the modulation signal output at the transmission timing of the j-th pulse among the k pulses in the burst pulse, and the corrected modulation signal is used as the k pulses in the next burst pulse. Waveform control means for outputting to the modulation means at the transmission timing of the j-th pulse of the pulses.

  In the present invention, when the excitation signal is subjected to pulse modulation with a modulation signal in which burst pulses composed of k pulses synchronized with the transmission timing are synthesized in time series, the waveform of the excitation signal is k. An error / correction signal corresponding to the error obtained by comparing the waveform of the monitor signal of the transmission output signal synchronized with the j-th pulse among the pulses, of the k pulses in the burst pulse. The modulation signal output at the transmission timing of the j-th pulse is corrected, and the corrected modulation signal is transmitted to the modulation means at the transmission timing of the j-th pulse among k pulses in the next burst pulse. Since the output is performed, the transmission output signal waveform can be automatically converged to the reference signal waveform.

  In order to achieve the above object, the automatic pulse waveform shaping system according to the fourth aspect of the invention is characterized in that the waveform control means according to the third aspect includes a reference signal generator and the waveform of the reference signal output from the reference signal generator. Are compared with the monitor signal waveform of the transmission output signal synchronized with the jth pulse of k pulses in the burst pulse, and output from the comparator and an error / correction signal. An error / correction signal generator for storing the error / correction signal, a modulation signal generator for storing the modulation signal output at the transmission timing of the j-th pulse among k pulses in the burst pulse, and an error An error / correction signal at the transmission timing of the j-th pulse among k pulses in the burst pulse output from the correction signal generator and a burst pulse output from the modulation signal generator As a modulated signal after correction at the transmission timing of the j-th pulse of k pulses in the next burst pulse by adding the modulation signal at the transmission timing of the j-th pulse among the pulses. Addition means for outputting to the modulation means.

  In order to achieve the above object, the automatic pulse waveform shaping system of the fifth invention is characterized in that the reference signal generator in the fourth invention has N types (where N is two or more according to the pulse characteristics or burst characteristics). Of the reference signal generator and a first switch for selecting one of the N types of reference signals, and the error / correction signal generator is a burst pulse. There are N first memory circuits and k first memory circuits each having k storage areas for separately storing error / correction signals at the time of transmission output signal synchronization in synchronization with transmission timings of k pulses in the middle. The error / correction signal at the transmission timing of the j-th pulse among the k pulses in the burst pulse is stored in the j-th storage area of the first memory circuit selected from the one memory circuit. 2 switcher , At the transmission timing of the jth pulse of the k pulses in the next burst pulse from the jth storage area of the selected first memory circuit among the N first memory circuits, The modulation signal generator includes a third switch that reads an error / correction signal at the transmission timing of the j-th pulse among k pulses in the previous burst pulse, and the modulation signal generator includes k pulses in the burst pulse. At the time of transmission output signal synchronization in synchronization with each transmission timing, N second memory circuits having k storage areas for separately storing modulated signals are selected from among the N second memory circuits. A fourth switch for storing the modulation signal at the transmission timing of the j-th pulse among k pulses in the burst pulse in the j-th storage area of one second memory circuit; From the jth memory area of the selected second memory circuit among the selected memory circuits at the transmission timing of the jth pulse among the k pulses in the next burst pulse. The fifth switch is configured to read a modulation signal at the transmission timing of the j-th pulse among the k pulses, and the first switch is selected according to the characteristics of one type of burst pulse used during transmission among the N types. It further has a switching signal generator for outputting a switching signal for switching control of the fifth to fifth switching devices.

  In the present invention, even when there are N types of pulse characteristics or burst characteristics of the modulation signal used for waveform shaping, there are N reference signals, a first memory circuit in the error / correction signal generator, and a modulation signal generation. By selecting one of the second memory circuit in the device and the first to fifth switches according to the pulse characteristics or burst characteristics of the modulation signal used for waveform shaping, the same as in the third invention. Thus, the transmission output signal waveform can be automatically converged to the reference signal waveform.

  In order to achieve the above object, according to the automatic pulse waveform shaping system of the sixth aspect of the invention, the power amplification means distributes the excitation signal waveform-shaped by the modulation means and distributes it into M (M is an integer of 2 or more). A power divider, M power amplifiers for separately amplifying M excitation signals output in parallel from the power divider, and excitation signals output after power amplification from the M power amplifiers. And a power combiner for combining the two. According to the present invention, a transmitter that transmits a transmission signal amplified with a large amount of power can output a transmission output signal amplified with a large amount of power even if the power amplification per power amplifier is small.

  The present invention shapes the excitation signal with a modulation signal, monitors the transmission output signal when power-amplifying and transmitting the excitation signal after waveform shaping, and compares the monitor signal waveform with the reference signal waveform. The error is corrected, the error is corrected to the previous modulation signal waveform to obtain the next modulation signal waveform, the next excitation signal is modulated with the corrected next modulation signal, and the pulse waveform shaping operation is repeated. Thus, the transmission output signal waveform can be automatically converged to the reference signal waveform, and thus has the following features.

  (1) By selecting a desired reference signal waveform, a transmission output signal waveform similar to the reference signal waveform can be obtained automatically and easily.

  (2) By matching the level of the reference signal to the monitor signal level when a desired transmission signal is output, the transmission output level can be automatically made constant. Also, the transmission output level can be easily varied by varying the reference signal level.

  (3) A high-power filter or a high-power waveform shaper is not required, and power loss due to these components can be eliminated.

  (4) Since the waveform is automatically shaped, the labor required to perform detailed waveform shaping according to each characteristic is eliminated by variation in characteristics of the power amplifier (semiconductor device), fluctuation of the excitation signal waveform, frequency characteristics, etc. be able to.

  Next, the best mode for carrying out the present invention will be described. FIG. 1 shows a block diagram of an embodiment of an automatic pulse waveform shaping system according to the present invention. This embodiment is applied to a pulse transmitter such as a navigation assistance device and a radar device. In FIG. 8, the same components as those in FIG. 8 are denoted by the same reference numerals.

The embodiment shown in FIG. 1 generates a transmission excitation signal by pulse-modulating the continuous wave or rectangular wave with the signal generator 1 that generates the continuous wave or rectangular wave and the modulation signal waveform from the waveform control circuit 9. a modulator 2 for a preamplifier 3 for amplifying a transmission excitation signal outputted from the modulator 2 to an input level of the power amplifier 5 ₁ to 5 _n, and the power amplifier 5 ₁ to 5 _n transmission excitation signal from the preamplifier 3 a power divider 4 to the same number of n distribution, and the power amplifier 5 ₁ to 5 _n for amplifying separately transmit excitation signals from the power divider 4 to the prescribed transmission power levels, each power in the power amplifier 5 ₁ to 5 _n A power combiner 6 that combines the amplified n transmission signals into one; a directional coupler 7 that extracts a portion of the combined transmission signal to monitor the combined transmission signal output from the power combiner 6; Exit from directional coupler 7 A detector 8 for detecting the combined transmission signal thus generated and generating a monitor signal, a reference signal, a reference signal waveform and a monitor signal waveform are compared, an error / correction signal is generated, and a previous modulated signal waveform is generated. And a waveform control circuit 9 for correcting the error / correction signal to generate a next modulated signal waveform.

  The waveform control circuit 9 is roughly composed of a reference signal generator 11, a comparator 12, an error / correction signal generator 14, a modulation signal generator 15, and an adder 16. The comparator 12 compares the reference signal waveform output from the reference signal generator 11 with the monitor signal waveform (transmission output signal waveform) output from the detector 8, and compares the comparison signal with an error / correction signal generator. 14. Based on the input comparison signal, the error / correction signal generator 14 generates an error / correction signal corresponding to the waveform error between the reference signal waveform and the monitor signal waveform (transmission output signal waveform).

  The adder 16 adds the above error / correction signal and the modulation signal generated from the modulation signal generator 15 based on the addition signal output from the adder 16 during the previous correction, and outputs the next modulation signal. Is supplied to the modulator 2 and is also supplied to the modulation signal generator 15 to generate the next modulation signal. In this way, by repeating the modulation of the next excitation signal with the next modulated signal with correction and performing the pulse waveform shaping, the transmission output signal waveform converges to the reference signal waveform and automatically A transmission output signal waveform similar to the waveform can be obtained.

  Next, the configuration and operation of the waveform control circuit 9 will be described in more detail. FIG. 2 is a block diagram of a waveform control circuit 9a which is an embodiment of the waveform control circuit 9 in FIG. In the figure, the same components as in FIG. In the waveform control circuit 9 a shown in FIG. 2, the comparator 12 compares the monitor signal 102 from the detector 8 with the reference signal 103 from the reference signal generator 11 and outputs an error / correction signal 104. The ADC 13 performs A / D conversion on the error / correction signal 104 and outputs error / correction data, which is a digital signal, to the error / correction signal generator 14.

  The error / correction signal generator 14 has a configuration in which two memories 141 and 142 are connected in cascade, and the modulation signal generator 15 also has a configuration in which two memories 151 and 152 are connected in cascade. When the waveform control circuit 9 outputs the modulation signal 101 in synchronization with the N-th transmission timing, the memory 151 among the memories 151 and 152 in the modulation signal generator 15 is the (N + 1) generation of the next timing. While storing the modulation signal data of the eye, the memory 152 outputs the (N-1) th modulation signal data of the immediately preceding timing.

  On the other hand, of the memories 141 and 142 in the error / correction signal generator 14, the memory 141 stores (N + 1) -th error / correction data at the next timing, and the memory 142 stores (N- 1) Output the first error / correction signal data. As a result, the adder 16 adds the (N−1) th error / correction signal data from the memory 142 and the (N−1) th modulation signal data from the memory 152 (N−). 1) Error correction is performed on the first modulation signal to generate Nth modulation signal data. The DAC 17 D / A converts the Nth modulation signal data and outputs the Nth modulation signal 101 which is an analog signal.

  Next, the operation of this embodiment will be described with reference to the timing chart of FIG. 3 together with FIGS. For the sake of easy understanding, an explanation will be given taking the Nth transmission output as an example. First, in accordance with the N-th transmission timing, the (N−1) -th modulation signal data (the first one is the same as the reference signal) and the error / correction signal from the memory 152 at the subsequent stage of the modulation signal generator 15. The (N−1) th error / correction signal data (the first one is error 0) is read from the memory 142 at the subsequent stage of the generator 14 and added by the adder 16 to be the next Nth error. Modulated signal data is generated.

  This modulation signal data is divided into two, and one of the N-th modulation signal data is D / A converted by the DAC 17 and is an analog signal as the N-th modulation signal 101 shown in FIG. It is output and used for modulation of the excitation signal transmitted at the Nth shot. The other N-th modulation signal data is stored in the first-stage memory 151 in the modulation signal generator 15 to be used as the (N + 1) -th modulation signal.

On the other hand, the continuous wave output from the signal generator 1 in FIG. 1 is output from the waveform control circuit 9 as described above in accordance with the transmission timing of the Nth transmission. Are modulated by the modulator 2 and become an excitation signal. This excitation signal is amplified to the input level of the power amplifiers 5 _{1 to} 5 _{n by} the preamplifier 3 shown in FIG. 1, then supplied to the power distributor 4 and distributed to n, and supplied to the power amplifiers 5 _{1 to} 5 _n , respectively. And separately amplified to a prescribed transmission power level. A total of n excitation signals respectively amplified by the power amplifiers 5 _{1 to} 5 _n are combined into a single signal by the power combiner 6, and then passed through the directional coupler 7 to be the Nth transmission output signal. Is output as

  At this time, in order to monitor the N-th transmission output signal, a part of the transmission signal is extracted by the directional coupler 7 shown in FIG. 1, and the N-th transmission output signal is detected by the detector 8. The Nth monitor signal is generated. The comparator 12 of the waveform control circuit 9 shown in FIG. 2 includes the waveform of the N-th reference signal 103 shown in FIG. 3C output from the reference signal generator 11 and the above-described waveform shown in FIG. The waveform of the Nth monitor signal is compared, and the error of the Nth error / correction signal 104 as shown in FIG. The Nth error / correction signal 104 is A / D converted by the ADC 13 to be converted into digital error / correction signal data and stored in the first-stage memory 141 in the error / correction signal generator 14.

  Next, the waveform control circuit 9 sends the Nth modulation signal data stored in the memory 151 in the modulation signal generator 15 shown in FIG. 2 and the error / correction signal before the (N + 1) th transmission starts. The Nth error / correction signal data stored in the memory 141 in the generator 14 is transferred to and stored in the subsequent memory 152 and memory 142, respectively.

  Subsequently, in accordance with the (N + 1) -th transmission timing, the waveform control circuit 9 transfers the N-th modulation signal data stored in the memory 152 and stores it in the memory 142. N-th error / correction signal data is output and added by an adder 16, and the N-th modulation signal is corrected with the N-th error / correction signal (N + 1) -th modulation signal. In order to create data and generate the (N + 2) -th modulation signal, this is stored in the memory 151, while the waveform control circuit 9 serves as the (N + 1) -th modulation signal 101 shown in FIG. To the modulator 2, where it is modulated with a continuous wave from the signal generator 1 to generate an (N + 1) th excitation signal.

The (N + 1) -th excitation signal is also amplified by the power amplifiers 5 _{1 to} 5 _n and then combined into a single signal by the power combiner 6. While being output as the first transmission output signal, a part is branched by the directional coupler 7, monitored by the detector 8 as the (N + 1) th transmission output signal, and output by the reference signal generator 11. The reference signal 103 is compared with the comparator 12 and the error is output as the (N + 1) th error / correction signal 104. Thereafter, the same operation as described above is repeated.

  In the same manner as described above, the modulation signal at the immediately previous transmission timing is corrected with the error / correction signal between the monitor signal and the reference signal of the transmission output signal transmitted at the immediately preceding transmission timing, and then modulated at the next timing. By repeating the generation of the excitation signal and transmission output signal of the next timing as a signal, the transmission output signal waveform converges to the reference signal waveform, and a transmission output signal waveform similar to the reference signal waveform is automatically obtained. It is done.

  As described above, according to the present embodiment, the transmission output signal waveform converges to the reference signal waveform. Therefore, a transmission output signal waveform similar to the reference signal waveform can be automatically obtained by selecting a desired reference signal waveform. In addition, by adjusting the reference signal level to the monitor signal level when the desired transmission output signal is output, the transmission output level can be automatically made constant, and the transmission output can be made by varying the reference signal level. The signal level can be easily varied.

Further, according to the present embodiment, a high power filter or a high power waveform shaper is not required, power loss due to these components can be eliminated, and further, a power amplifier (power semiconductor device) 5 is provided. ₁ to 5 _n of characteristic variations, variations in the excitation signal waveform, the frequency characteristic other, it is unnecessary to detailed waveform shaping according to the respective characteristics, can be eliminated their effort.

  Next, another embodiment of the present invention will be described. In another embodiment of the present invention, the pulse characteristics (pulse width, rise / fall time, single / pair pulse) and burst characteristics (basic pulse, number of pulses, pulse interval) of the transmission output signal are used for each pulse group. Divide and provide a function to output and store each modulation signal and error / correction signal for each pulse group, a function to output a reference signal for each pulse group, and a function to select this according to the type of pulse group Thus, it is possible to cope with the types of pulse characteristics and burst characteristics of the transmission signal. This is because the correction for each pulse in the embodiment described with reference to FIGS. 1 to 3 may not be corrected.

  Since a burst has a duty cycle that is about a dozen times that of a single pulse, the characteristics of the power amplifier change in a short time due to unavoidable causes such as temperature rise and power supply drop. Therefore, the transmission output signal that is not corrected fluctuates. For ease of explanation, a burst pulse for outputting three transmission output signals (a pulse train composed of three burst pulses) is shown as an example in FIG. One burst pulse is, for example, a pulse train composed of three pulses each having a pulse width of about 3.0 to 3.5 μs and inputted in a cycle of 30 μs.

  As shown in FIG. 4 (B), the transmission output signal of the first burst without correction is the output of the reference signal level shown in FIG. 4 (A). As the pulse progresses to the 2nd and 3rd pulse, the transmission output signal decreases as shown in FIG. 5B. However, the burst and the power and the state of the power supply return to the original in the 2nd burst. The same output characteristics as the first shot.

  On the other hand, FIG. 5 shows an example in which correction for each pulse is added as in the above embodiment. When correction is performed for each pulse, as shown in FIG. 5 (B), an error from the reference signal level shown in FIG. As shown in FIG. 4D, it is 0. As a result, the second modulated signal of the transmission output signal is the same as the first modulated signal as shown in FIG. As shown in FIG. 5B, the level of the current level decreases by 0.2.

  As a result, the second error becomes 0.2 as shown in FIG. 5 (D), and the error is added to the second modulation signal, and the third error as shown in FIG. 5 (A). The modulation signal is at a level 0.2 higher than the reference signal. Therefore, the third transmission output signal level decreases by 0.4 without correction, but only decreases by 0.2 as shown in FIG.

  As a result, the third error becomes 0.2 as shown in FIG. 5D, and the error is added to the third modulation signal, so that the third error as shown in FIG. The modulation signal is at a level 0.2 higher than the reference signal. As a result, as shown in FIG. 5 (A), the modulation signal of the first transmission output of the second burst is the third error with a third error 0.2 and a level higher by 0.2 than the reference signal. The modulation signal is added to obtain a modulation signal that is 0.4 larger than the reference signal.

  Accordingly, the first transmission output signal level of the second burst is 0.4 larger than the reference signal as shown in FIG. 5B, and the error from the reference signal shown in FIG. As shown in the figure (D), it becomes -0.4. Thereafter, as a result of the same operation, the result is as shown in FIG. 5, and the transmission output signal level does not converge to the reference signal level. This is because an error in a different state is corrected while the state at the time of transmission output changes.

  For this reason, in order to correct the error in the same state while the state at the time of transmission output changes, the burst is made one pulse group, the first transmission output of the first burst is the transmission output of the second burst. 1st burst, 1st burst output, 2nd burst output, 2nd burst output, 2nd burst output, 1st burst output, 3rd burst burst, 2nd burst This problem was solved by correcting each error at the third transmission output.

This is another embodiment of the present invention. FIG. 6 shows a block diagram of a waveform control circuit 9b which is a main part of another embodiment of the automatic pulse waveform shaping system according to the present invention. In the figure, the same components as those in FIG. The configuration other than the waveform control circuit 9b is the same as the configuration of FIG. In the waveform control circuit 9b shown in FIG. 6, the reference signal generator 11 includes reference signal generators 111 _{1 to} 111 _N that generate N pulse group reference signals, and these reference signal generators 111 _{1 to} 111 _N. And a switch 112 for selectively outputting one reference signal 103 from the output reference signals.

  Further, the error / correction signal generator 14 includes memory circuits 144-1 to 144 -N each including two cascade-connected memories for generating / storing modulation signal data for every N pulse groups; A switch 143 that switches the error / correction signal data supplied to the circuits 144-1 to 144 -N for each pulse group, and one of the error / correction signal data output from the memory circuits 144-1 to 144 -N. It comprises a switch 144 for selecting and outputting error / correction signal data.

  Further, the modulation signal generator 15 includes memory circuits 154-1 to 154-N including two cascaded memories for generating / storing modulation signal data for every N pulse groups, and a memory circuit 154. A switch 153 that switches the modulation signal data supplied to −1 to 154 -N for each pulse group, and one modulation signal data is selected from the modulation signal data output from the memory circuits 154-1 to 154 -N. It comprises a switch 154 that outputs. Further, it has a pulse group switching unit 18 for supplying a pulse switching signal 105 to the switching units 112, 143, 145, 153 and 155 in accordance with the type of the pulse group of the transmission signal and selectively switching the pulse group. This embodiment is an embodiment that can cope with the case where the burst pulse has N types of characteristics (when the number of pulse groups is N).

  That is, in the error / correction signal generator 14 and the modulation signal generator 15, the memory circuits have N kinds of burst pulses as indicated by 144-1 to 144-N and 154-1 to 154-N, respectively. N circuits are provided corresponding to the memory circuits 144-1 to 144 -N in the error / correction signal generator 14 and the memory circuits 154-1 to 154-N in the modulation signal generator 15. If each burst pulse is composed of k pulses, each has k storage areas, and errors and corrections when k pulses of the previous burst pulse are output to the k storage areas. Signal data and modulation signal data are stored corresponding to each pulse.

  Next, the operation of the present embodiment will be described. In the case of the second output of a certain m-th burst pulse (in the case of the burst m-th transmission output), the modulation signal generator 15 is synchronized with the transmission timing of the selected second pulse. Are stored in the second storage area of the subsequent memory in the memory circuit of the pulse group selected by the switch 155 (here, 154-1 is taken as an example), (m−1) th The second modulation signal of the burst pulse (the first one is the same as the reference signal of the selected pulse group) is output, while the error / correction signal generator 14 selects the pulse group selected by the switch 145. The second error / correction signal (initially error 0) of the (m−1) th burst pulse, which is stored in the second storage area of the memory subsequent to the memory circuit 144-1, is output. , They are added by the adder 16, 2 shots th modulated signals originating th burst pulse is generated.

This modulated signal is divided into two parts, one of which is D / A converted by the DAC 17 and output to the modulator 2 in FIG. It is used for modulation of the excitation signal transmitted at the second transmission output of the eye, and the other is used as the modulation signal of the second transmission output of the burst (m + 1) transmission, so that the switch 153 of the modulation signal generator 15 is used. It is stored in the memory at the first stage of the memory circuit 154-2 of the selected pulse group 2. As described with reference to FIG. 1, the signal extracted from the modulator 2 is transmitted through the preamplifier 3, the power distributor 4, the power amplifiers 5 _{1 to} 5 _n , the power combiner 6, and the directional coupler 7. While output as the second transmission output, it is detected by the detector 8.

The monitor signal 102 with the second transmission output from the detector 8 from the detector 8 is compared with the reference signal 1111 of the _first pulse group selected by the switch 112 in the reference signal generator 11 of FIG. The comparator 12 compares the errors and outputs the error as a second error / correction signal 104. The error / correction signal 104 is A / D converted by the ADC 13 and then stored in the second memory of the first stage memory of the memory circuit 144-1 of the pulse group selected by the switch 143 of the error / correction signal generator 14. Stored in the area.

  Before the third transmission starts, the second memory of the first stage of each of the memory circuit 154-1 of the selected pulse group of the modulation signal generator 15 and the memory circuit 144-1 of the error / correction signal generator 14 is used. Each second data stored in the storage area is transferred to the other memory at the subsequent stage and stored in the second storage area. Thereafter, the burst (m−1) th read out from the third storage area of the memory circuits 144-1 and 154-1 of the pulse group of the transmission signal is synchronized with the third pulse transmission timing of the burst pulse. The error / correction signal data and modulation signal data for the third transmission output are selected, and the above operation is repeated. Similarly, by repeating this operation, the transmission output signal waveform can be converged to the reference signal waveform for each pulse group.

  Therefore, according to this embodiment, as shown in FIG. 7, the error (= reference signal−monitor signal (=) of the first transmission output of the first burst, the first transmission output of the second burst, etc. The transmission output signal)) is 0 as shown in FIG. 7D, and the monitor transmission output is at the same level as the reference signal shown in FIG. 7A as shown in FIG. Further, the second transmission output of the first burst is +0.2 as shown in FIG. 4D, and the monitor transmission output is −0.2 from the reference signal as shown in FIG. Although the error decreases, the modulation signal of the second burst signal obtained by adding the error and the second modulation signal output of the first burst transmission is +0.2 as shown in FIG. Become.

  Further, the transmission output of the first burst is -0.4 as shown in FIG. 5B, and an error from the reference signal shown in FIG. The signal-monitor signal (transmission output signal)) has an error of +0.4 as shown in FIG. Accordingly, the modulation signal of the third transmission output of the burst 2 obtained by adding the error and the modulation signal output of the third transmission output of the burst is as shown in FIG. , +0.4. As a result, each transmission output after the second burst can output a signal having the same level as the reference signal as shown in FIG. 7C, as shown in FIG. 7B.

  Thus, in this embodiment, the first transmission output of the first burst is the first transmission output of the second burst, the second transmission output of the first burst is the transmission of the second burst. The transmission output level of the second output, the third transmission output of the first burst, and the third transmission output of the second burst are error-corrected to make the transmission output level constant automatically. The transmission output signal level can be easily varied by varying the reference signal level.

Further, according to the present embodiment, a high power filter or a high power waveform shaper is not required, power loss due to these components can be eliminated, and further, a power amplifier (power semiconductor device) 5 is provided. ₁ to 5 _n of characteristic variations, variations in the excitation signal waveform, the frequency characteristic other, it is unnecessary to detailed waveform shaping according to the respective characteristics, can be eliminated their effort.

  The present invention can be used for a generation method of a high power transmission signal used in a DME / TACAN device, a pulse radar device, or the like.

It is a block diagram of one embodiment of the present invention. It is a block diagram of one embodiment of a waveform control circuit in the system of the present invention. 3 is a timing chart for explaining the operation of FIG. 2. It is operation | movement explanatory drawing in the case of no correction | amendment. It is operation | movement explanatory drawing in the case of correction | amendment for every pulse. It is a block diagram of other embodiments of the waveform control circuit in the system of the present invention. FIG. 7 is an operation explanatory diagram in the case of correction for each pulse group according to FIG. 6. It is a block diagram of an example of the prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Signal generator 2 Modulator 3 Preamplifier 4 Power divider 51-5n Power amplifier 6 Power combiner 7 Directional coupler 8 Detector 9, 9a, 9b Waveform control circuit 11 Reference signal generator 12 Comparator 13 ADC
14 Error / correction signal generator 15 Modulation signal generator 16 Adder 17 DAC
18 pulse group switching device 101 modulation signal 102 monitor signal 103 reference signal 104 error / correction signal 105 pulse group switching signal 111 _{1 to} 111 _N pulse group reference signal 143, 145, 153, 155 switching device 144-1 to 144N, 154 1-154-N memory circuit

Claims (6)

Modulation means for shaping the waveform by pulse-modulating the excitation signal with a modulation signal of a pulse train synchronized with the transmission timing;
A power amplifying means for amplifying the power of the excitation signal that has been waveform-shaped and output by the modulating means;
Branching means for bifurcating the excitation signal power amplified by the power amplification means, one of which is output as a transmission output signal in synchronization with the transmission timing;
Detecting means for detecting the other transmission output signal branched by the branching means and outputting a monitor signal;
Including a reference signal generator, obtained by comparing the waveform of the reference signal output from the reference signal generator with the waveform of the monitor signal output from the detection means, And a waveform control unit that corrects the modulation signal output at the previous transmission timing with the correction signal and outputs the corrected modulation signal to the modulation unit at the next transmission timing. Pulse waveform shaping method. The waveform control means includes
The reference signal generator;
A comparator that compares the waveform of the reference signal output from the reference signal generator with the waveform of the monitor signal and outputs the error / correction signal;
An error / correction signal generator for storing the error / correction signal output from the comparator;
A modulation signal generator for storing the modulation signal output at the previous transmission timing;
At the next transmission timing, the error / correction signal at the previous transmission timing output from the error / correction signal generator, and the modulation signal at the previous transmission timing output from the modulation signal generator; 2. The automatic pulse waveform shaping method according to claim 1, further comprising: adding means for adding to the modulation means and outputting the corrected modulation signal at the next transmission timing to the modulation means. Modulation means for shaping a waveform by pulse-modulating a burst signal composed of k pulses (where k is an integer of 2 or more) synchronized with the transmission timing of the excitation signal in a time-series manner;
A power amplifying means for amplifying the power of the excitation signal that has been waveform-shaped and output by the modulating means;
Branching means for bifurcating the excitation signal power amplified by the power amplification means, one of which is output as a transmission output signal in synchronization with the transmission timing of the burst pulse;
Detecting means for detecting the other transmission output signal branched by the branching means and outputting a monitor signal;
A reference signal generator, the waveform of the reference signal output from the reference signal generator, and the j-th of the k pulses in the burst pulse output from the detection means (however, j is an error / correction signal corresponding to the error obtained by comparing the waveform of the monitor signal of the transmission output signal synchronized with the pulse of any pulse in the range of 1 to k). The modulation signal output at the transmission timing of the j-th pulse among the k pulses is corrected, and the corrected modulation signal is converted into j of the k pulses in the next burst pulse. And a waveform control means for outputting to the modulation means at the transmission timing of the second pulse. The waveform control means includes
The reference signal generator;
The waveform of the reference signal output from the reference signal generator is compared with the waveform of the monitor signal of the transmission output signal synchronized with the jth pulse among the k pulses in the burst pulse. A comparator that outputs the error / correction signal;
An error / correction signal generator for storing the error / correction signal output from the comparator;
A modulation signal generator for storing the modulation signal output at the transmission timing of the j-th pulse among the k pulses in the burst pulse;
The error / correction signal at the transmission timing of the j-th pulse among the k pulses in the burst pulse output from the error / correction signal generator, and the modulation signal generator. The modulation signal at the transmission timing of the j-th pulse among the k pulses in the burst pulse is added, and the j-th pulse of the k pulses in the next burst pulse is added. 4. An automatic pulse waveform shaping system according to claim 3, further comprising: an adding unit that outputs the modulated signal after correction at the transmission timing to the modulating unit. The reference signal generator includes a reference signal generator that generates N types of reference signals (where N is an integer of 2 or more according to pulse characteristics or burst characteristics), and one type of the N types of reference signals. And a first switch for selecting a reference signal of
The error / correction signal generator has k storage areas for separately storing the error / correction signals at the time of transmission output signal synchronization in synchronization with transmission timings of the k pulses in the burst pulse. Of the k pulses in the burst pulse, there are N first memory circuits and the jth storage area of the first memory circuit selected from the N first memory circuits. A second switch for storing the error / correction signal at the transmission timing of the j-th pulse, and the j-th storage of the first memory circuit selected from the N first memory circuits. From the region, at the transmission timing of the j-th pulse among the k pulses in the next burst pulse, the transmission timing of the j-th pulse among the k pulses in the previous burst pulse. More becomes a third switching unit for reading the error-corrected signal in the ring,
The modulation signal generator includes a second memory having k storage areas for separately storing the modulation signals at the time of transmission output signal synchronization in synchronization with transmission timings of the k pulses in the burst pulse. There are N circuits and the jth memory area of the second memory circuit selected from among the N second memory circuits has the jth of the k pulses in the burst pulse. From the jth storage area of the second memory circuit selected from among the N second memory circuits and the fourth switch for storing the modulated signal at the pulse transmission timing of the next time The transmission timing of the jth pulse among the k pulses in the burst pulse, and the transmission timing of the jth pulse among the k pulses in the previous burst pulse. More becomes fifth switching device for reading the tone signal,
The apparatus further comprises a switching signal generator for outputting a switching signal for switching control of the first to fifth switching devices according to characteristics of one type of burst pulse used at the time of transmission among the N types. Item 5. The automatic pulse waveform shaping method according to Item 4. The power amplifying unit distributes the excitation signal waveform-shaped and output by the modulating unit to M (M is an integer of 2 or more), and M power units that are output in parallel from the power distributor. M power amplifiers for separately amplifying the excitation signals, and a power combiner for combining the excitation signals output from the M power amplifiers after being amplified. The automatic pulse waveform shaping method according to any one of claims 1 to 5.

Images