Amplifier output automatic control method and device

Abstract

The present application discloses a method for automatic control of power amplifier output: measuring and saving the first correlation data between output frequency and gain control voltage, and measuring and saving the second correlation data between output power and temperature; searching in the first correlation data and the second correlation data in turn according to the target output power and the target output frequency, and performing power amplifier output according to the initial gain control voltage determined by the search; periodically measuring the current actual output power, and calculating the current difference between the actual output power and the target output power; if the current difference is outside the tolerance range, after lowering the target output power, searching in the first correlation data and the second correlation data in turn, and performing power amplifier output according to the adjusted gain control voltage determined by the search. The present application has formulated the first correlation data and the second correlation data, and after setting the target output power and the target output frequency, the gain control voltage can be quickly confirmed by searching, which greatly improves the efficiency of power amplifier control.

Description

Technical Field

[0001] The present application relates to the field of communications, and in particular to a method and device for automatically controlling output of a power amplifier. Background Art

[0002] The application field of power amplifier is very wide, from household appliances such as audio, television, microwave oven, etc. to civilian products such as repeater, TV tower, etc., power amplifiers can be found. The factors that affect the output power of the power amplifier are mainly: ambient temperature, electrical signal frequency, electrical signal phase. There are two methods for regulating the power amplifier: gain control and amplitude control. However, how to ensure that a series of parameters such as the output power, echo, and background noise of the power amplifier are stable and controllable so that the output power reaches the target power has always been the focus and difficulty of research. Summary of the invention

[0003] The purpose of the present application is to at least partially overcome the deficiencies of the prior art and to provide a fast and stable power amplifier output automatic control method and device.

[0004] In order to achieve the above technical objectives, the technical solutions adopted in this application are as follows:

[0005] First, a method for automatic control of power amplifier output is provided, which comprises the following steps:

[0006] For a specified power amplifier, first correlation data between output frequency and gain control voltage is measured and saved, and second correlation data between output power and temperature is measured and saved;

[0007] Searching in the first associated data and the second associated data in sequence according to the target output power and the target output frequency, and performing power amplifier output according to the initial gain control voltage determined by the search;

[0008] Periodically measure the current actual output power and calculate the current difference between the actual output power and the target output power;

[0009] The current difference is outside the tolerance range, and after lowering the target output power, the first associated data and the second associated data are searched in sequence, and the power amplifier output is performed according to the adjusted gain control voltage determined by the search.

[0010] Specifically, the method for obtaining the first associated data is as follows:

[0011] Select characteristic frequency points within the intended output frequency range;

[0012] Determining the gain control voltage corresponding to different output powers in each of the characteristic frequency points;

[0013] Arranging the data obtained by the measurement to form a table of the first associated data;

[0014] The method for obtaining the second associated data is as follows:

[0015] Determining the compensation voltage corresponding to different temperatures in each of the characteristic frequency points;

[0016] The data obtained by the measurement are sorted to form a table of the second correlation data.

[0017] Preferably, the number of the characteristic frequency points is at least 5; the characteristic frequency points include two end values ​​of the intended output frequency range.

[0018] Further preferably, the difference between the different output powers is 5-10W; the difference between the different temperatures is 0.2-2°C.

[0019] Further preferably, the table of the first associated data and the table of the second associated data are stored in a flash format.

[0020] Preferably, the method for lowering the target output power is as follows:

[0021] The original target output power is subtracted from half of the current difference to obtain the adjusted target output power, which is used to determine the adjusted gain control voltage.

[0022] Optionally, a method for determining whether the current difference is outside the tolerance range is one of the following:

[0023] Specifying an upper limit interval value and a lower limit interval value based on the target output power fluctuation, when the current difference value is greater than the upper limit interval value or less than the lower limit interval value, it is considered that the current difference value is outside the tolerance range;

[0024] The accumulated value of the difference values ​​obtained in the most recent several measurement cycles is calculated. When the accumulated value is greater than 1W, it is considered that the current difference value is outside the tolerance range.

[0025] Preferably, the upper limit interval value is 0 to 1W; the lower limit interval value is -1 to 0W; and the number of most recent measurement cycles is 3 to 8.

[0026] Furthermore, if the current difference is within a tolerance range, output control of the power amplifier is suspended.

[0027] Secondly, an automatic control device for power amplifier output includes a processing chip and a storage medium, one or more programs are stored in the storage medium and are configured to be executed by the processing chip, and the one or more programs are used to drive the processing chip to execute the automatic control method for power amplifier output as described above.

[0028] Compared with the prior art, this application has the following advantages:

[0029] (1) The method of the present application establishes first correlation data between output frequency and gain control voltage and second correlation data between output power and temperature. After setting the target output power and target output frequency, the gain control voltage can be quickly confirmed by searching. The background operation is fast, which greatly improves the efficiency of automatic control of the power amplifier.

[0030] (2) The method of the present application has simple and clear operation logic, clear boundaries and termination conditions, is stable and not prone to errors, and is suitable for long-term operation;

[0031] (3) The first associated data and the second associated data of the method of the present application are both stored in the flash in a table format, which greatly improves the security of the data and the speed of calculation;

[0032] (4) The method of the present application can handle situations where the output power of the power amplifier is offset due to various factors, and can quickly adjust the output power in a variety of complex environments.

[0033] (5) The method and device of the present application are applicable to a variety of power amplifier systems, including signal source systems, and are suitable for integration into the software of an embedded monitoring system to monitor and automatically control the power amplifier system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a flow chart of the automatic control method of power amplifier output of this application. DETAILED DESCRIPTION

[0035] The present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0036] The power amplifier involved in this application has rich application scenarios, ranging from household appliances such as audio, television, and microwave ovens to civil equipment such as repeaters and TV towers. Therefore, in order to improve the applicability of the method involved in this application to a specified power amplifier, it is necessary to measure and debug the power amplifier in a specific scenario. The following article takes a repeater as an example to describe in detail the power amplifier output automatic control method of this application.

[0037] The power amplifier output automatic control method of the present application comprises the following steps:

[0038] S1, for a specified power amplifier, measuring and saving first correlation data between output frequency and gain control voltage, and measuring and saving second correlation data between output power and temperature;

[0039] The first associated data is about the correspondence between the output frequency and the gain control voltage. In the prior art, the output frequency can be adjusted by adjusting the gain control voltage. However, the mathematical correspondence between the gain control voltage and the output frequency is relatively complex, and there is a large deviation in this correspondence for different power amplifiers. In order to simplify the calculation, this application first formulates a "standard correspondence table". The second associated data is about the correspondence between the output power and the temperature. Determining the second associated data can further calibrate the output power of the power amplifier. For power amplifiers in other application scenarios, other associated data can also be formulated in a targeted manner, such as the associated data between output power and phase.

[0040] Specifically, it is assumed that the frequency range of the electrical signal output by the power amplifier control in this embodiment is 2400MHz-2500MHz, and five characteristic frequency points 2400MHz, 2425MHz, 2450MHz, 2475MHz, and 2500MHz are taken within the frequency range 2400MHz-2500MHz, including two end values ​​of the frequency range. Next, at the frequency point of 2400MHz, the corresponding relationship between the output frequency and the gain control voltage is calculated: 10W-1508mV, 20W-1564mV, 30W-1620mV, 40W-1676mV, 50W-1716mV... In the same way, the corresponding relationship between the output frequency and the gain control voltage at the frequency points of 2425MHz, 2450MHz, 2475MHz, and 2500MHz is calculated. The data obtained by the measurement is sorted and compiled into a flash table of the first associated data for storage.

[0041] Furthermore, the second correlation data between output power and temperature can be obtained through the test of the high and low temperature box. After calculation, this embodiment knows that when the temperature is less than 35°C, the gain control voltage needs to be compensated by 1mV for every 1°C decrease. The data obtained by the measurement is sorted and compiled into a flash table of the second correlation data for storage.

[0042] In summary, the method for calculating the first associated data and the second associated data is as follows:

[0043] Select characteristic frequency points within the intended output frequency range; those skilled in the art should know that the more characteristic frequency points there are, the higher the accuracy of the first associated data and the second associated data, but the calculation workload also increases accordingly. Usually, the number of characteristic frequency points is at least 5 and must include the two end values ​​of the frequency range;

[0044] Determine the gain control voltage corresponding to different output powers in each of the characteristic frequency points, preferably, the difference between the different output powers is 5 to 10W, so as to achieve a certain measurement accuracy;

[0045] Arranging the data obtained in the previous step of measurement to form a table of the first associated data;

[0046] Determine the compensation voltage corresponding to different temperatures in each of the characteristic frequency points, preferably, the difference between the different temperatures is 0.2-2° C., so as to achieve a certain measurement accuracy;

[0047] The data obtained from the previous step of measurement are sorted to form a table of the second correlation data.

[0048] S2, searching in the first associated data and the second associated data in turn according to the target output power and the target output frequency, and performing power amplifier output according to the initial gain control voltage determined by the search;

[0049] Specific search method: Assuming that the target output power currently set in this embodiment is 50W and the target output frequency is 2430MHz, the gain control voltage corresponding to the two frequency points of 2425MHz and 2450MHz in the first associated data table is calculated. After measuring the current ambient temperature, the initial gain control voltage is calculated based on the compensation voltage corresponding to the two frequency points of 2425MHz and 2450MHz in the second associated data table, and the power amplifier output is performed with the initial gain control voltage value.

[0050] S3, periodically measuring the current actual output power and calculating the current difference between the actual output power and the target output power;

[0051] The current difference is outside the tolerance range, and after lowering the target output power, the first associated data and the second associated data are searched in sequence, and the power amplifier output is performed according to the adjusted gain control voltage determined by the search.

[0052] Otherwise, the output control of the amplifier is suspended.

[0053] In this embodiment, after the power amplifier output is performed by the initial gain control voltage determined in the previous step, the actual output power of the power amplifier system is measured, and the actual output power of the power amplifier system is 55W. There is a tolerance between the target output power and the actual output power. Within the tolerance range, it can be considered that the actual output power has basically reached the target output power, and the power amplifier system has reached a stable state, and no intervention adjustment is required. If the following situations occur, it is considered that the difference between the target output power and the actual output power is outside the tolerance range:

[0054] (i) specifying an upper limit interval value and a lower limit interval value based on the target output power fluctuation, when the current difference value is greater than the upper limit interval value or less than the lower limit interval value, the current difference value is considered to be outside the tolerance range; preferably, the upper limit interval value is 0 to 1W; the lower limit interval value is -1 to 0W; in this embodiment, the target output power is 50W, the actual output power is 55W, and the current difference value is 5W, which exceeds the upper limit interval value, and the current difference value is considered to be outside the tolerance range;

[0055] (ii) Calculate the cumulative value of the difference values ​​obtained in the most recent several measurement cycles. When the cumulative value is greater than 1W, it is considered that the current difference value is outside the tolerance range. Preferably, the most recent several measurement cycles are 3 to 8. In this embodiment, the cumulative value of the latest 5 difference values ​​is greater than 1W (the current difference value is 5W, which is greater than 1W), and the current difference value is considered to be outside the tolerance range.

[0056] The current difference is outside the tolerance range, and the target output power needs to be adjusted to adjust the output power of the power amplifier. The specific adjustment method is: the original target output power is subtracted from one-half of the current difference to obtain the adjusted target output power. For this embodiment, the calculation formula for the adjusted target output power is 50-(55-50) / 2=47.5 W. With 47.5 W as the new target output power, the first associated data and the second associated data are searched again in the aforementioned manner to obtain the adjusted gain control voltage, and the power amplifier output is performed with the adjusted gain control voltage value.

[0057] In fact, it is difficult to adjust the target output power and gain control voltage in one go, and multiple approximations are required. For this, a measurement cycle needs to be set. After the current cycle ends, the current output power is measured again in the next cycle, and it is determined whether the difference between the target output power and the actual output power is outside the tolerance range. If the current difference is outside the tolerance range, the target output power is adjusted again and the gain control voltage is determined again. Otherwise, the output control of the power amplifier is suspended and the last updated state is maintained.

[0058] Furthermore, the present application also provides an automatic control device for power amplifier output, which includes a processing chip and a storage medium, one or more programs are stored in the storage medium and configured to be executed by the processing chip, and the one or more programs are used to drive the processing chip to execute the automatic control method for power amplifier output as described above.

[0059] In a possible implementation manner, the power amplifier automatic control device of the present application includes:

[0060] A timer, used to calculate the measurement cycle;

[0061] A processing chip, used to analyze and process the received data signal within the measurement period, send instruction information to other parts of the power amplifier output automatic control device, and execute a preset program;

[0062] A memory, used to record first correlation data between output frequency and gain control voltage, second correlation data between output power and temperature, other preset information and other real-time recorded data, for analysis and processing by the controller;

[0063] Furthermore, if Figure 1 As shown, the processing chip is driven by the program stored in the memory to execute the power amplifier output automatic control method as described above: searching in the first associated data and the second associated data in turn according to the target output power and the target output frequency, and performing power amplifier output according to the initial gain control voltage determined by the search; periodically measuring the current actual output power, and calculating the current difference between the actual output power and the target output power; if the current difference is outside the tolerance range, after lowering the target output power, searching in the first associated data and the second associated data in turn again, and performing power amplifier output according to the adjusted gain control voltage determined by the search.

[0064] The power amplifier output automatic control device can be integrated into an embedded monitoring system to monitor and automatically control the power amplifier system.

[0065] In summary, the method and device of the present application establish the first correlation data between the output frequency-gain control voltage and the second correlation data between the output power-temperature. After setting the target output power and the target output frequency, the gain control voltage can be quickly confirmed by searching, and the background operation is fast, which greatly improves the efficiency of automatic control of the power amplifier.

[0066] The above embodiments are preferred implementation modes of the present application, but are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present application should be equivalent replacement methods and are included in the protection scope of the present application.

Claims

1. A method for automatic control of power amplifier output, characterized in that: It includes the following steps: For a specified power amplifier, first correlation data between output frequency and gain control voltage is measured and saved, and second correlation data between output power and temperature is measured and saved; Searching in the first associated data and the second associated data in sequence according to the target output power and the target output frequency, and performing power amplifier output according to the initial gain control voltage determined by the search; Periodically measure the current actual output power and calculate the current difference between the actual output power and the target output power; The current difference is outside the tolerance range, and after lowering the target output power, the first associated data and the second associated data are searched in sequence, and the power amplifier output is performed according to the adjusted gain control voltage determined by the search; the method for lowering the target output power is as follows: the original target output power is subtracted from one half of the current difference to obtain the adjusted target output power, which is used to determine the adjusted gain control voltage; The target output power is adjusted multiple times so that the actual output power and the target output power are close to each other, and when the current difference is within the tolerance range, the output control of the power amplifier is suspended.

2. The method according to claim 1, characterized in that The method for obtaining the first associated data is as follows: Select characteristic frequency points within the intended output frequency range; Determining the gain control voltage corresponding to different output powers in each of the characteristic frequency points; Arranging the data obtained by the measurement to form a table of the first associated data; The method for obtaining the second associated data is as follows: Determining the compensation voltage corresponding to different temperatures in each of the characteristic frequency points; The data obtained by the measurement are sorted to form a table of the second correlation data.

3. The method according to claim 2, characterized in that The number of the characteristic frequency points is at least 5; the characteristic frequency points include two end values ​​of the intended output frequency range.

4. The method according to claim 2, characterized in that The difference between the different output powers is 5-10W; the difference between the different temperatures is 0.2-2°C.

5. The method according to claim 2, characterized in that The table of the first associated data and the table of the second associated data are stored in a flash format.

6. The method according to claim 1, characterized in that The method for determining whether the current difference is outside the tolerance range is one of the following: Specifying an upper limit interval value and a lower limit interval value based on the target output power fluctuation, when the current difference value is greater than the upper limit interval value or less than the lower limit interval value, it is considered that the current difference value is outside the tolerance range; The accumulated value of the difference values ​​obtained in the most recent several measurement cycles is calculated. When the accumulated value is greater than 1W, it is considered that the current difference value is outside the tolerance range.

7. The method according to claim 6, characterized in that The upper limit interval value is 0~1W; the lower limit interval value is -1~0W; and the most recent number of measurement cycles is 3~8.

8. A power amplifier output automatic control device, characterized in that: It includes a processing chip and a storage medium, one or more programs are stored in the storage medium and are configured to be executed by the processing chip, and the one or more programs are used to drive the processing chip to execute the method for automatic control of power amplifier output as described in any one of claims 1 to 7.

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