CN209072461U - Radio-frequency power amplifier dynamic power adjusts device - Google Patents

Abstract

The utility model discloses radio-frequency power amplifier dynamic powers to adjust device, is arranged between the equipment and antenna for generating radiofrequency signal, including radio frequency amplifier and RF coupler；It further include filter, radiofrequency power detector, micro-control unit and supply voltage and substrate bias controller, the output end of the RF coupler is also connected with the input terminal of the filter, the output end of the filter connects the input terminal of the radiofrequency power detector, the output end of the radiofrequency power detector connects the input terminal of the micro-control unit, the output end of the micro-control unit connects the input terminal of the supply voltage and substrate bias controller, and the supply voltage connects the input terminal of the radio frequency amplifier with the output end of substrate bias controller.

Description

RF Power Amplifier Dynamic Power Adjustment Device

technical field

The utility model belongs to the field of communication, in particular to a radio frequency power amplifier technology used for indoor coverage of mobile communication, in particular to a dynamic power adjustment device of the radio frequency power amplifier.

Background technique

At present, in the existing indoor coverage application scenario, the RF power amplifier, as the last stage of the transmitter, plays the function of amplifying the modulated signal to the required power value and sending it to the antenna for transmission, ensuring that the signal is transmitted within a certain area. The receiver can receive high enough signal levels without interfering with adjacent channel signals.

In the existing indoor coverage environment, in order to meet the fringe field strength, considering the gain of omnidirectional ceiling antenna or directional antenna, the final power amplifier should meet the maximum linear power output +17dBm (for example, the modulation mode 64QAM needs to meet ACPR-45dBc). When selecting RF power amplifiers, considering cost and performance factors, such power amplifiers mostly use class AB, which will be used according to the signal peak-to-average ratio to perform linearity fallback processing to ensure that the power amplifier works linearly in the linear region and avoid saturation distortion. Ensure that the adjacent channel leakage and vector magnitude error (EVM) meet the standard requirements, and consider adding a margin to ensure stability while ensuring the peak-to-average ratio.

for example:

Peak-to-average ratio: 10dB;

Output power: +17dBm;

Design margin: 2dB.

The selection of RF power amplifier should meet:

17dBm+10dB+2dB=29dBm

That is, the RF power amplifier with P1dB greater than 29dBm should be selected to meet the system requirements.

However, when covering wiring in a mobile communication room, multiple passive devices, such as cables, connectors, power dividers and couplers, need to pass between the device that generates the radio frequency signal and the antenna, and the device that generates the radio frequency signal passes through each antenna. The number of passive components used is different, and the connection quality of each component during construction is also different, resulting in the power of the RF signal reaching the antenna varies greatly, which seriously deviates from the theoretical power of the design. It is very common that the traditional active antenna final stage AB radio frequency power amplifier has a fixed compression point according to the peak-to-average ratio and the nominal output power, and cannot be adjusted, which will introduce the following problems:

(1) The power consumption is large and fixed, regardless of the size of the input and output signals;

(2) For the remote power supply system, the pressure on the power supply is large;

(3) The power amplifier causes the temperature of the remote unit to increase, which accelerates the aging process.

In view of this, the present invention is proposed.

Utility model content

The purpose of the utility model is to provide a dynamic power adjustment device of a radio frequency power amplifier, which solves the problems of high power consumption, high power supply pressure and rapid aging of the remote machine caused by the inability of the power amplifier to adjust the maximum output power.

In order to achieve the above purpose, the utility model provides a dynamic power adjustment device for a radio frequency power amplifier, which is arranged between a device that generates radio frequency signals and an antenna, and includes a radio frequency amplifier and a radio frequency coupler, and the device that generates radio frequency signals is connected to the radio frequency amplifier. The input end of the radio frequency amplifier, the output end of the radio frequency amplifier is connected to the input end of the radio frequency coupler, and the output end of the radio frequency coupler is connected to the antenna;

It also includes a filter, a radio frequency power detector, a micro-control unit, and a supply voltage and bias voltage controller. The output end of the radio frequency coupler is also connected to the input end of the filter, and the output end of the filter is connected to the The input end of the radio frequency power detector, the output end of the radio frequency power detector is connected to the input end of the micro control unit, the output end of the micro control unit is connected to the input end of the supply voltage and the bias voltage controller, so The output end of the supply voltage and bias voltage controller is connected to the input end of the radio frequency amplifier.

Preferably, the filter is a passive filter.

Further, the micro-control unit is a single-chip microcomputer with ADC function and/or DAC function.

The dynamic power adjustment device of the radio frequency power amplifier provided by the utility model has the following beneficial effects:

1. The power amplifier is designed as a closed loop, and the power amplifier state is dynamically adjusted through output power detection to achieve the purpose of reducing power consumption and saving energy consumption;

2. For the remote power supply system, the power supply pressure is reduced;

3. The power consumption is reduced, which reduces the temperature of the remote machine and slows down the aging process.

Description of drawings

FIG. 1 is a schematic structural diagram of an apparatus for dynamic power adjustment of a radio frequency power amplifier according to a specific embodiment.

In the picture:

1. RF amplifier 2. RF coupler 3. Filter 4. RF power detector 5. Micro-control unit 6. Supply voltage and bias controller.

Detailed ways

In order to make those skilled in the art better understand the solution of the present invention, the present invention will be further described in detail below with reference to the specific embodiments.

A dynamic power adjustment device for a radio frequency power amplifier, which is arranged between a device that generates a radio frequency signal and an antenna, and includes a radio frequency amplifier 1, a radio frequency coupler 2, a filter 3, a radio frequency power detector 4, a microcontroller unit 5 (MCU) and a power supply voltage With the bias voltage controller 6, the output end of the radio frequency amplifier 1 is connected to the input end of the radio frequency coupler 2, the output end of the radio frequency coupler 2 is connected to the input end of the filter 3, and the output end of the filter 3 is connected to the radio frequency power detector 4. The input end, the output end of the radio frequency power detector 4 is connected to the input end of the micro-control unit 5, the output end of the micro-control unit 5 is connected to the input end of the supply voltage and the bias voltage controller 6, and the output end of the supply voltage and the bias voltage controller 6 The terminal is connected to the input terminal of the radio frequency amplifier 1 .

Filter 3 selects a passive filter (LC filter or SAW filter) according to the frequency band used. The easy-to-use passive filter structure is to connect the inductor and capacitor in series, which can filter the main harmonics (3, 5, 7). ) constitutes a low-impedance bypass, the LC filter is relatively easy to manufacture, has a low price, and can be applied in a wide frequency band, which is widely used in communications, instrumentation and other fields; filter 3 is mostly selected to use a band-pass filter. The band-pass filter can filter out unwanted signals, which is simpler to install, simpler to design and use, and smaller in size.

Micro-control unit 5 (MCU) should choose to use a microcontroller with ADC (analog-to-digital converter) function, which can sample the analog signal of continuous variable. The micro-control unit 5 (MCU) can choose to use a single-chip microcomputer with a DAC (digital-to-analog converter) function, and adjust the output analog voltage through algorithm calculation to output analog voltages of different amplitudes to adjust the amplifier bias voltage.

The input end of the RF amplifier 1 receives the signal and amplifies the power of the signal. The amplified signal enters the RF coupler 2, and the RF coupler 2 couples the signal power at a fixed ratio and sends it to the filter 3, and the filter 3 passes the band from it. Select, extract the desired signal, filter the undesired signal, and after extracting the desired signal, transmit the desired signal to the radio frequency power detector 4, and the radio frequency power detector 4 converts the detected different signal powers into different voltage values, the radio frequency The power detector 4 converts the signal power into voltage and sends the voltage to the micro-control unit 5. After the micro-control unit 5 collects the voltage value, it completes the calculation of the output power through a related algorithm; when the output power is lower than the predetermined power of the theoretical output, According to the characteristics of the power amplifier tube, the microprocessor unit can be a linear function ax-b or a logarithmic formula or other algorithm formula, or a list of the sampling voltage corresponding to the power, that is, the bias voltage corresponding to different power is linearly reduced or other corresponding relationship, the dynamic power adjustment device can be activated, and the power supply voltage and the bias voltage controller 6 are adjusted by the micro-control unit 5. The power supply voltage and bias voltage controller 6 reduces the output level of the power supply voltage and the bias voltage, thereby reducing the power amplifier The purpose of maximum output power is to reduce power consumption and save energy consumption. The signal after adjusting and reducing the voltage and output level is sent to the antenna for use through RF amplifier 1 and RF coupler 2; when the output power is not lower than the theoretical output When the predetermined power is reached, the dynamic power adjustment device does not need to be activated, and the received signal is directly sent to the antenna through the radio frequency amplifier 1 and the radio frequency coupler 2 for use.

Example 1

Existing room division common networking, that is 1RRU-1 near-end unit - 40 remote active antennas, the power consumption of the remote unit of the active system is about 4W, and the power consumption of the RF amplifier 1 (PA) selected for the final stage About 1.175, accounting for more than 25% of the total power consumption, P-1dB is 30dBm; start the dynamic power adjustment device, reduce the output level of the supply voltage and bias voltage through the supply voltage and bias voltage controller 6, and reduce the maximum output of the power amplifier Power, test the P-1db corresponding to different paranoid voltages, the test shows that when the P-1dB is reduced from 30dBm to 27dBm, the power consumption can be reduced to 0.65W, and a single remote active antenna can reduce the power consumption by about 0.5W. 40 remote units can reduce the total power consumption by 20W. In the case of 4G or 5G indoor coverage widely using MIMO technology, 40 remote units with dual channels can reduce the power consumption by 20×2=40W.

Specific examples are used herein to describe the inventive concept in detail, and the descriptions of the above embodiments are only used to help understand the core idea of the present invention. It should be pointed out that for those skilled in the art, without departing from the inventive concept, any obvious modifications, equivalent replacements or other improvements made should be included within the protection scope of the present invention .

Claims (3)

1. The dynamic power adjustment device of a radio frequency power amplifier is arranged between a device that generates a radio frequency signal and an antenna, including a radio frequency amplifier and a radio frequency coupler, and the device that generates a radio frequency signal is connected to the input end of the radio frequency amplifier, and the output of the radio frequency amplifier is connected. The end is connected to the input end of the radio frequency coupler, and the output end of the radio frequency coupler is connected to the antenna; it is characterized in that, It also includes a filter, a radio frequency power detector, a micro-control unit, and a supply voltage and bias voltage controller. The output end of the radio frequency coupler is also connected to the input end of the filter, and the output end of the filter is connected to the The input end of the radio frequency power detector, the output end of the radio frequency power detector is connected to the input end of the micro control unit, the output end of the micro control unit is connected to the input end of the supply voltage and the bias voltage controller, so The output end of the supply voltage and bias voltage controller is connected to the input end of the radio frequency amplifier. 2 . The dynamic power adjustment device according to claim 1 , wherein the filter is a passive filter. 3 . 3 . The dynamic power adjustment device according to claim 1 , wherein the micro-control unit is a single-chip microcomputer with an ADC function and/or a DAC function. 4 .