RU2800490C1 - Phase correction system for amplification channels of a solid-state transmitter - Google Patents

Abstract

FIELD: solid state transmitters.

SUBSTANCE: invention discloses a block diagram and an algorithm of operation, the totality of which provides correction of the phases of the amplification channels of a solid-state transmitter in the operating frequency range, compensating for the existing differences in the electrical lengths of the elements of the distribution summing path and amplifying modules, by changing the phases of the microwave signal in (n -1) amplification channels, by means of a controlled discrete phase shifter integrated into each amplifying module, by the values of the calculated phase corrections. The output power is estimated by the ADC according to the level of the microwave power envelope at three frequencies of the operating range.

EFFECT: increased summing efficiency and output power of a solid-state transmitter, reduced requirements for the identity of the electrical lengths (phases) of the elements of the distribution-summing path of the transmitter and to amplifying modules, and facilitated layout process.

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Description

This invention relates to the field of solid-state transmitters with microwave power summation in special summators (adders) and serves to increase the summation efficiency and increase the output power of a solid-state transmitter.

Methods of phase correction are known from the prior art (for example, UDC 621.396.67, Elimination of phase errors on the elements of the short-wave antenna array by compensating for the phase shift in the feeder, V.I. Nevzorov, P.V. Savochkin, S.Yu. Semin , R. G. Nikitin; patent No. 2115222, Device for compensating the phase shift in the feedback circuit of a power amplifier (options), Per-Set Tor Bergsten, Jan-Christian Nystrom; patent No. 150918 Solid-state power amplifier, Kotov A. P. Vyboldin Yu.K.).

The technical result to which the present invention is directed is to increase the efficiency of summing the output powers of solid-state microwave amplifiers (4.1-4.n) and increase the output power of the transmitter (1), which includes the proposed correction system. Another achievement is a lighter layout of the transmitting device, in the form of removing restrictions from its components (distribution-summing path (3, 5, 15.1-15.n, 16.1-16.n), solid-state amplifying modules (4)) in terms of requirements for identity of electrical lengths (phases).

These technical results are provided by a combination of the following technical solutions:

1. a controlled discrete phase shifter (10) is introduced into each amplifying module (4),

2. all amplifying modules (4) of the transmitter (1) are added in turn with the same module - the reference one (for example, the first one (4.1)) and the phase correction of all other amplification channels is performed relative to the phase of this channel (for example, the first one (4.1) ).

3. part of the output microwave power after the adder (5) is diverted by means of a directional coupler (6) for analysis,

4. branched power is estimated by the level of the microwave power envelope obtained after detection by the amplitude detector (7) and analog-to-digital conversion (9) in the control and monitoring device (8),

5. after the power is estimated, the phase shifter (10) of the power amplifier (not the reference one) is rebuilt in accordance with the proposed phase correction algorithm,

6. The start of the phase correction procedure is carried out by the operator from his workplace (13), by issuing the appropriate command from the user menu during adjustment or maintenance work (if necessary).

This power amplifier (4) must have the following properties:

a) the composition must include a discrete phase shifter with electronic control (10),

b) the tuning range of the phase shifter (10) must be at least 360° with a nominal phase change increment of 5.625° (6 bits),

c) the restructuring of the phase shifter (10) must be carried out by the integrated control device (11) according to the received commands from the external control and monitoring device (8) in relation to the amplifying module,

d) the integrated control device (10) of the amplifying module (4) must provide the ability to turn the module on and off according to commands received from the external control and monitoring device (8).

This command and control device (8) must have the following properties:

a) the composition must include an ADC (9) with a clock frequency sufficient to obtain at least 10 samples of the envelope of the output microwave power during one test pulse, to ensure sufficient accuracy in estimating the output power and the quality of the phase correction being carried out,

b) (8) must receive and transmit commands to control amplifying modules from the automatic monitoring and control system (14)

(4), as well as transmit information about the modules (4) to the automatic monitoring and control system (14),

c) perform part of the phase correction algorithm in terms of enabling/disabling modules (4), controlling phase shifters (10), estimating the output power.

This directional coupler (6) must have the following properties:

a) be located as close as possible to the output of the power adder (5),

b) have transient attenuation such as to provide at the input of the amplitude detector (7) an acceptable value of the output power with an ideal (lossless) summation of two amplifying modules (4).

This amplitude detector (7) must have the following properties:

a) the amplitude of the output voltage at the input power corresponding to the ideal addition (lossless) of two amplifying modules must not overload the input of the ADC (9),

b) have thermal stabilization circuits that equalize the characteristics of the detector (7) in the range of operating temperatures.

To ensure the operability of the phase correction system, the following algorithm for the functioning of the correction system must be implemented, the block diagram of which is shown in figure 1.

The phase correction algorithm is launched by the operator from the information processing and display system (12) by activating the corresponding key of the software graphical interface on the monitor of the automatic monitoring and control system (14) of the operator’s workplace (13). In this case, the signal conditioner (2) begins to generate a test signal at the lower operating frequency ƒ _n , which differs from the signal used in normal operation by a fixed duration and repetition period (no wobbles). This is necessary to synchronize the ADC when performing output power level estimation and improve the accuracy of this estimation.

Further, (14) sends to (8) the command to turn on the first amplifying module (4.1). After switching on (4.1), at the input (9) the pulse voltage of the envelope of the detected output microwave signal arrives and the procedure for estimating the output power (4.1) P _outM1 (ƒ _n ) at a frequency ƒ _n is performed and recorded in memory (8). After that, (14 ₎ sequentially sets the average and upper frequency _of the signal ƒ _{with and} ƒ _in respectively, for which the estimation and recording of the output power ( _{4.1 )} frequency ƒ _in .

At the next step of the algorithm, (14) turns on the amplifying module (4.2), without turning off (4.1), and the total value of the power P _{outPU1 + AMP2} (ƒ _in ) of modules (4.1) and (4.2) is estimated at a frequency ƒ _in . Then, (14) gives a command to change the phase of the controlled phase shifter of the module (4.2) by 32 increments, which corresponds to a change in the phase of the output signal of the module (4.2) by 180°. Accordingly, the result of summing the output powers (4.1) and (4.2) P' _{vyhUM1 + UM2} (ƒ _in ), which is shown in figure 2, also changes. This value is also recorded.

At the initial moment of the algorithm operation, between the module (4.1) and (4.2) there will be a phase difference Δϕ, and after the phase increment of the module (4.2) by 32 samples:

At the next step, the phase correction algorithm calculates, using the proposed expression (2), the phase correction value (γ) of the module (4.2) at the upper operating frequency ƒ _in , necessary for the in-phase summation of the modules (4.1) and (4.2) at a given frequency.

where m is the nominal value of the discrete phase increment of the phase shifter of the module (4.2), k is the normalization coefficient (determined by the transient attenuation of the adder), Р _{outPU1 + MP2} is the result of estimating the output power of the joint work (4.1) and (4.2) with the initial phase of the module (4.2) , P' _vyuM1+UM2 - the result of the estimation of the output power of joint work (4.1) and (4.2) after the increment of the initial phase of the module (4.2) by 180° (32 samples).

The calculated value of the module phase correction (4.2) for the upper operating frequency is stored in the memory (14) and the cycle described above is repeated for the middle and lower frequencies of the operating range.

Thus, memory (14) accumulates three values of the phase corrections for the module (4.2) - γ _UM2 (ƒ _n ), γ _UM2 (ƒ _s ), γ _UM2 (ƒ _in ). Based on the correction values γ _AM2 (ƒ _n ), γ _AM2 (ƒ _c ), γ _AM2 (ƒ _in ) obtained at three points of the operating frequency range, the average value - γ _AM2 is calculated, which is rounded up to an integer and written to the non-volatile memory of the module ( 4.2). After that, module (4.2) is turned off, module (4.3) is turned on, and two nested loops of the phase correction algorithm are repeated.

Thus, the phases of the amplification channels of the transmitter (1), in which solid-state amplifying modules (4.1-4.n) are installed, are adjusted in turn to the phase of the amplification channel in which the module (4.1) is installed, after which the test signal is turned off, and the phase algorithm correction is completed.

DESCRIPTION OF THE SCHEME

The block diagram of the phase correction system for amplification channels of a solid-state transmitter is shown in figure 3 and consists of an n-channel solid-state transmitter (1) (signal shaper (2), n powerful amplifying modules (4), a distribution summing system based on a divider (3 ) and an adder (5), connecting feeders (15, 16), a directional coupler (6), a control and monitoring device (8) with an integrated ADC (9) and an amplitude detector (7)), an information processing and indication system (12) with an automatic monitoring and control system (14), software that implements the algorithm for the functioning of the phase correction system and a control interface at the operator's workplace (13).

The input microwave signal of a low power level from the shaper (2) is fed to the n-channel switchgear - power divider (3), the outputs of which are connected to the inputs of the amplifying modules (4) by connecting feeders (15). The outputs of the amplifying modules are connected by means of connecting feeders (16) to a power adder (5), the output of which is connected to the waveguide-feeder path through a directional coupler (6). Each module (4) has a controlled six-bit phase shifter (70) that changes the phase of the input signal in the range from 0° to 360° with a nominal tuning step of 5.625°. The phase shifters (10) are controlled, the modules (4) are switched on and off by an integrated control device (11) as part of each module (4) by commands from the control and monitoring device (8). Also, the ADC (9) of the control and monitoring device (8) receives the detected envelope of the output signal of the transmitting device, which is formed by a thermally stabilized amplitude detector (7) connected to the attenuated output of the directional coupler (6). The envelope value is estimated in (8) and, together with the ability to control the phase of the output signal of each amplifier, is the basis for the operation of the phase correction algorithm.

IMPLEMENTATION OF THE INVENTION

The technical result provided by the combination of the above features is an increase in the summation efficiency and an increase in output power, facilitating the process of setting up the elements of the distribution-summing path (3, 15, 16, 5), as well as amplifying modules (4), due to the absence of the need for phase requirements.

Claims (1)

Phase correction system of amplification channels, consisting of n solid-state power amplifiers (4) of the same type, each of which includes a controlled discrete phase shifter (10) with a control device (11), and the tuning range of the phase shifter (10) must be at least 360° with a minimum change phase is not more than 5.625°, while solid-state power amplifiers (4) are connected via connecting feeders (15) to the n-channel divider (3) and connected via connecting feeders (16) to the adder (5) of microwave power, which is connected to a directional coupler (6), one output of which is the output of the claimed system, the other output is connected to the detector (7), the output of which is connected to the ADC (9), which is part of the control and monitoring device (8), which is connected to the control device (11) of each solid-state power amplifier (4), while the control and monitoring device (8) is also connected to the automatic monitoring and control system (14) associated with the operator’s workplace (13) and with a low-power microwave signal generator (2), output which is connected to the input of the n-channel divider (3), and the output powers (n-1) of the amplifying modules (4) are added in turn to the output power of one reference module (4) and the result of the addition is evaluated, while the output power is evaluated sequentially on three frequencies of the operating range, based on the results of which the value of the phase correction of the phase shifter of the module is calculated, the power of which at the current step of the algorithm is summed with the power of the reference module, for each of the three frequencies of the operating range, followed by averaging the corrections obtained for the three frequencies of the operating range and recording this averaged value in non-volatile memory of the control device (11) of the module, the power of which at the current step of the algorithm is added to the power of the reference module.