KR100659718B1 - Method and Apparatus for detecting 1xEV-DO power in RF power amplifer - Google Patents

Abstract

The present invention relates to a method of detecting 1xEV-DO power in an RF power amplifier, comprising: converting a magnitude of power amplified by the power amplifier into a voltage, converting the converted voltage into digital data, and then converting the digital data. Sampling asynchronously, storing the sampled data in a buffer, sorting in size order to obtain a mode switch point, using the obtained mode switch point to determine a mode of 1xEV-DO, and an error value according to the determined mode. To compensate for this, the 1xEV-DO signal can be detected by software change without hardware change in the power detector used in the conventional power amplifier.

Power Amplifier, 1xEV-DO, Error Compensation, Power Detection

Description

METHOD AND APPARATUS FOR DETECTING 1x EV-DO power in RF power amplifer

1 is a view showing the structure of a typical 1xEV-DO frame.

2A and 2B show modes of a typical 1xEV-DO signal.

Figure 3 is a block diagram schematically showing the configuration of an apparatus for detecting 1xEV-DO power in the RF power amplifier according to the present invention.

4 is a flowchart illustrating a method of detecting power of 1 × EV-DO using a power detection device according to the present invention.

5A-5E are waveform diagrams showing the output of a power detector for a 1xEV-DO signal in accordance with the present invention.

6 is a diagram for explaining a mode switch point for mode division of a 1xEV-DO signal according to the present invention;

7 is a view showing a mode switching point value of each mode of the 1xEV-DO signal according to the present invention.

<Explanation of symbols for the main parts of the drawings>

300: power amplifier 310: power detector

320: DC level amplifier 330: A / D conversion unit

340: control unit

The present invention analyzes the output of the power detector without additional external information to determine the mode of the 1x EV-DO (1x Evolution-Data Optimized) signal that is currently input / output, RF power amplifier for compensating the power error according to each mode It relates to a 1xEV-DO power detection method and apparatus.

Code Division Multiple Access 2000 (CDMA 2000) and 1xEV-DO communicate data using the same 1.25 MHz wide radio as the existing IS-95B / cdma2000 1x, so the system sector continues to use IS-95B / cdma2000 1x. Many parts make it easy to coexist with these facilities. Therefore, the use of RF power amplifiers that can accommodate the existing CDMA and 1xEV-DO is required.

In general, a power amplifier is a kind of amplifier and refers to an amplifier for the purpose of supplying power to a load. The power amplifier is divided into a low frequency power amplifier and a high frequency power amplifier according to the handling frequency, and it is important to be able to supply power to the load with little distortion and efficiently. For this reason, power transistors are often used in transistor amplifiers.

The 1xEV-DO signal is designed for data only. The TDM (Time Division Multiplexer) method is used for allocating data to the user, and various modulation methods such as QPSK, 8PSK, and 16QAM are used. Implementing an RF power amplifier that can accept signals of a different type than the IS-95B / cdma2000 1x requires a new power detection method that can accurately measure power levels.

1xEV-DO divides transmission data into frame units as shown in FIG. 1, and one frame includes 16 slots. One slot consists of various additional information data including data. 1xEV-DO saves the data fields in the slots in the active or idle state according to the communication situation with the user, and the characteristics of the signal in five modes according to the data configuration of the slots in the active and idle states. This is distinguished.

Since CDMA or 1xEV-DO are ultimately spread at the same chip rate, when two signals are measured with power detectors, two signals of the same power can be measured to approximately the same size. However, 1xEV-DO changes output depending on the presence or absence of data. That is, it can be seen that when the data section of the slot is idle, no signal is measured in this section.

FIG. 2A illustrates the case of 1xEV-DO 100%. Since the data field sections of the slots are all active, the result of the measurement using the power detector does not differ significantly from that of the CDMA signal. The output voltages of the power detectors of the two signals have the same magnitude and waveform. However, when 1xEV-DO is 75%, 50%, 25%, and idle as shown in FIG. 2B, there is an idle section in the slot, and since there is no signal in this section, the waveform of the voltage measured by the power detector Is measured as a square wave of constant padfen. Importantly, not only is the waveform different for each mode, but the magnitude of the measured voltage is measured differently for each mode of 1xEV-DO.

Therefore, the signal change according to the 1xEV-DO mode cannot be conventionally used in the power amplifier. That is, because the current measured voltage cannot be used as control information of the power amplifier due to the change of the measured value according to each mode of 1xEV-DO, the constant power measurement value is extracted and the 1xEV-DO is compensated for the error of each mode. It should be possible to tell which mode DO is.

For this purpose, the compensation of 1xEV-DO can be easily handled if information about the mode of 1xEV-DO is provided from an external system. However, in a conventionally designed power amplifier or maintenance / maintenance power amplifier to add 1xEV-DO function, It is difficult to apply and the newly designed power amplifier has many disadvantages that the system side does not provide mode information for 1xEV-DO.

Accordingly, an object of the present invention is to provide a method and apparatus for detecting 1xEV-DO power in an RF power amplifier that can distinguish a mode of a currently input / output 1xEV-DO signal by analyzing the output of the power detector without any external information. have.

According to an aspect of the present invention to achieve the above object, in the method for detecting 1xEV-DO power in the RF power amplifier, converting the amount of power amplified in the power amplifier to a voltage, and converting the converted voltage After converting to digital data, the digital data is asynchronously sampled, the sampled data is stored in a buffer, and then, in order of size, a mode switch point is obtained, and the mode of the 1xEV-DO is obtained by using the obtained mode switch point. There is provided a 1xEV-DO power detection method in an RF power amplifier, characterized in that for determining and compensating for an error value according to the determined mode.

The mode switch point refers to a point where the size of the data changes rapidly when the sampled data is sorted in order of size, and the value is determined for each mode.

Determining the mode of 1xEV-DO using the obtained mode telephone point compares a mode switch point value obtained through a configuration ratio of high level data and low level data through a chip with a predetermined switch point value for each mode to determine the corresponding mode. To judge.

According to another aspect of the present invention, in the apparatus for detecting 1xEV-DO power in the RF power amplifier for amplifying and outputting the input power, the DC level by measuring the input power, output power and reflected power of the power amplifier A power detector to extract, a DC level amplifier to amplify a predetermined level of the DC level extracted by the power detector, an A / D converter to convert the DC level amplified by the DC level amplifier into a digital value, the A / D conversion And a controller for sampling the digital data converted by the unit, determining a mode of an output signal by obtaining a mode switching point using the sampled data, and compensating for an error according to the determined mode. An apparatus for detecting 1xEV-DO power in an amplifier is provided.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 3 is a block diagram schematically showing the configuration of an apparatus for detecting 1xEV-DO power in the RF power amplifier according to the present invention.

Referring to FIG. 3, an apparatus for detecting 1 × EV-DO power in an RF power amplifier includes a power amplifier 300 for amplifying and outputting input power, and input power, output power, and reflected power of the power amplifier 300. A power level detector 310 for measuring and extracting a DC level, a DC level amplifier 320 for level amplifying the DC level extracted by the power detector 310 to a DC level suitable for input of an A / D converter, and the DC level The A / D converter 330 converts the DC level amplified by the amplifier 320 into a digital value, and the digital data converted by the A / D converter 330 is sampled, and the sampled data is used. The controller 340 may determine a mode of an output signal by obtaining a mode switch point, and compensate the error according to the determined mode.

The power detector 310 envelopes peak power and outputs a magnitude of power as a voltage.

An RC low pass filter (not shown) is configured in the DC level amplifier 320 to remove noise and high frequency components while maintaining the shape of the output waveform of the power detector 310.

The controller 340 asynchronously samples at least four slots asynchronously with respect to the voltage output from the A / D converter 330, and stores the sampled data in a buffer and arranges them in order of size.

Then, the controller 340 obtains a point where the size rapidly changes, that is, a mode switch point, for the sorted data. That is, the controller 340 obtains the mode switch point from the ratio of the configuration of the high level and the low level data in the sorted data. Here, the mode switch point is a point where the size of the data is rapidly changed when the data formed by the two groups of the high level data and the low level data is changed in size, and the ratio of the two data groups in each mode is different and own It has a specific ratio, and refers to the change position of the level obtained by the specific ratio in the entire data.

When the mode switch point is obtained, the controller 340 determines the mode of 1xEV-DO using the obtained mode switch point, and compensates an error value according to the determined mode. For example, if the mode switch point is 0.854, 1xEV-DO is 75%, and if 0.707, 1xEV-DO is 50%, the error value is compensated for each mode.

A method of detecting 1xEV-DO power using the 1xEV-DO power detection device configured as described above will be described in detail with reference to FIG. 4.

4 is a flowchart illustrating a method of detecting power of 1xEV-DO using a power detection apparatus according to the present invention, and FIGS. 5A to 5E are waveforms illustrating an output of a power detector for a 1xEV-DO signal according to the present invention. 6 is a view illustrating a mode switch point for mode division of a 1xEV-DO signal according to the present invention, and FIG. 7 is a view illustrating values of mode switch points for each mode of the 1xEV-DO signal according to the present invention.

Referring to FIG. 4, the power detection apparatus outputs a magnitude of power amplified by the power amplifier as a voltage (S400).

That is, the power detection device envelopes the peak power of the power amplified by the power amplifier and outputs the magnitude of the power as a voltage.

The output voltage is as shown in Figs. 5a to 5e.

FIG. 5A illustrates that the data field sections of the slots are all active in the case of 1xEV-DO 100%, and there is no difference from the CDMA signal.

In FIG. 5B, in the case of 1xEV-DO 75%, an idle section B exists in the slot. Since there is no signal in this section, the waveform of the voltage measured by the power is measured as a square wave of a constant pattern.

Looking at the measured square wave, the square wave is divided into a high level and a low level. Here, the high level region C represents data of a slot, MAC, Pilot, etc., and the low level region D represents no data in the slot.

In addition, the waveform should be an accurate square wave, but appears as a square wave distorted by a filter or the like.

In FIG. 5C, in the case of 1xEV-DO 50%, an idle section B exists in the slot. Since there is no signal in this section, the waveform of the voltage measured by the power is measured as a square wave of a constant pattern.

Looking at the measured square wave, the square wave is divided into a high level and a low level. Here, the high level region C represents data of a slot, MAC, Pilot, etc., and the low level region D represents no data in the slot.

In FIG. 5D, in the case of 1xEV-DO 25%, an idle section B exists in a slot. Since there is no signal in this slot, the waveform of the voltage measured by the power is measured as a square wave of a constant pattern.

Looking at the measured square wave, the square wave is divided into a high level and a low level. Here, the high level region C represents data of a slot, MAC, Pilot, etc., and the low level region D represents no data in the slot.

5E illustrates a case of 1xEV-DO idle, in which there is no data section in the slot and only idle section B exists. Looking at the measured square wave, the square wave is divided into a high level and a low level. Here, the high level region C indicates MAC, Pilot, etc., and the low level region D indicates that there is no data in the slot.

After performing step 400, the power detection apparatus converts the output voltage into digital data and asynchronously samples the digital data (S402). At this time, since each mode of the 1xEV-DO is classified into a configuration ratio between an active slot and an idle slot, at least four slots must be sampled to determine the mode.

In the sampling method, sampling is performed asynchronously without synchronizing with 1xEV-DO frame, so at least 1/3 or 1/2 frame of 1xEV-DO should be sampled to obtain data that can be used for mode classification. That is, one frame consists of 16 slots, and in the case of 1xEV-DO 75%, 12 active slots and four idle slots exist in one frame. That is, one frame has a pattern in which the active slot and the idle slot are 'AAAI AAAI AAAI AAAI'. Here, 'A' refers to the active slot, 'I' refers to the idle slot.

In the case of 1xEV-DO 50%, since there are 8 active slots and 8 idle slots in one frame, the pattern becomes 'AIAI AIAI AIAI AIAI'.

In addition, in the 1xEV-DO idle mode, since all 16 slots of one frame are idle slots, the pattern becomes 'IIII IIII IIII IIII'.

Therefore, at least four slots must be observed to determine the mode of 1xEV-DO, so sample at least four slots.

Which frame of information is sampled can be adjusted according to the system's specifications, and the more sampling, the higher the accuracy.

After performing step 402, the apparatus for detecting power stores the sampled data in a buffer, sorts the data in size order (S404), and obtains a mode switch point of the sorted data (S406).

Since the data sampling is asynchronous, the occupancy time of the high level signal and the low level signal changes, so it is necessary to estimate the time ratio between the low level and the high level of the signal according to the data change for each 1xEV-DO signal.

When the sampling data is aligned, the ratio change between the high level and the low level can find a switch point that converges to the final level as shown in FIG. 6, and the signal can be distinguished by identifying the position of the switch point.

Referring to FIG. 6, the data distribution is the same for the CDMA and 1xEV-DO 100% signals, and for the remaining 1xEV-DO signals, the positions of convergence to the final level differ according to the data ratio. The signals of 1xEV-DO are clearly distinguished by the data distribution before and after the point.

The location of the points is affected by asynchronous sampling, but the 1xEV-DO signal can be distinguished by the data distribution before and after each point.

In order to calculate the position of the mode switching point of each mode, the position in the sampled data group is estimated using the chip, which is the minimum data unit of the slot, not the time unit. The problem here is that since sampling is performed asynchronously, the position of the mode switch point may change depending on the number of slots being sampled. For example, in the case of 1xEV-DO 75%, the entire signal repeats the AAAI pattern. When sampling six slots, the AAAIAA pattern and the IAAAIA pattern can be read according to the sampling time. To solve this problem, the mode change point size due to the pattern change becomes almost constant if enough slots are read.

Assuming that enough data is sampled from enough slots, the four slots provide enough insight into the overall characteristics. Through the chip, the mode switch point is obtained from the composition ratio of high level and low level data.

The mode switch point will be described with reference to FIG. 7.

Referring to FIG. 7, since 1xEV-DO 100% is a signal having a constant magnitude, all samples are high level data when sampled.

Since 1xEV-DO 75% has an A / A / A / I pattern, the mode switching point is 6992/8192 = 2046 * 3 + 848 * 1 = 6992 chips, that is, 6882 chips among the 8192 chips appear as high-level signals. 0.854.

Since 1xEV-DO 50% has an A / I / A / I pattern, the mode switching point is 5792/8192 = 0.797 because 2048 * 2 + 848 * 2 = 5792 chips, or 5792 chips of all 8192 chips, appear as high-level signals. do.

Since 1xEV-DO 25% has an A / A / A / I pattern, the mode switching point is 4592/8192 = 0.56 because 2048 * 1 + 848 * 3 = 4592 chips, or 4592 chips out of all 8192 chips, appear as high signals. .

Since the 1xEV-DO idle has an I / I / I / I pattern, the mode switching point is 3392/8192 = 0.414 because 858 * 4 = 3392 chips, that is, 3392 chips of the total 8192 chips, appear as high level signals.

When the mode switch point is obtained as described above, the power detection apparatus determines the mode of 1xEV-DO using the obtained switch point (S408) and compensates for an error value according to the determined mode (S410).

For example, if the obtained mode switch point is 0.854, it is determined as 1xEV-DO 75% and the error value is compensated accordingly. If the mode switch point is 0.797, it is determined as 1xEV-DO 50% and other error values are compensated.

The present invention is not limited to the above embodiments, and many variations are possible by those skilled in the art within the spirit of the present invention.

As described above, according to the present invention, a method and apparatus for detecting 1xEV-DO power in an RF power amplifier capable of detecting a 1xEV-DO signal with only a software change without a hardware change in a power detecting apparatus used in a conventional power amplifier. Can be provided.

In addition, according to the present invention, since the algorithm is used to compensate for the error of power by dividing the signal by itself, a method and apparatus for detecting 1xEV-DO power in an RF power amplifier that can be used even without providing information on an input signal separately from an external system. Can provide.

In addition, according to the present invention, it is possible to provide a method and apparatus for detecting 1xEV-DO power in an RF power amplifier that can be easily implemented in a low-cost system because it does not require high-specific hardware or high-speed computation.

Claims (9)

A method for detecting 1xEV-DO power in an RF power amplifier, Converting the amount of power amplified by the power amplifier into a voltage; Converting the converted voltage into digital data and asynchronously sampling the digital data; Storing the sampled data in a buffer and then arranging them in order of size to obtain a mode switch point; Determining a mode of 1xEV-DO by using the obtained mode switch point, and compensating for an error in power according to the determined mode 1xEV-DO power detection method in the RF power amplifier comprising a. The method of claim 1, Converting the magnitude of the power amplified by the power amplifier to a voltage, characterized in that for enveloping (peak) the peak power of the power amplified by the power amplifier to convert the magnitude of power to a voltage and outputs 1xEV-DO power detection method in an RF power amplifier. The method of claim 2, The output voltage is a 1xEV-DO power detection method of the RF power amplifier, characterized in that the square wave having a high level region indicating that the data is present in the slot and the low level region indicating no data in the slot. The method of claim 1, In the asynchronous sampling of the digital data, each mode of 1xEV-DO is classified into a configuration ratio of an active slot and an idle slot, so that at least four slots are sampled. Power detection method. The method of claim 1, The mode switch point refers to a point where the size of the data changes drastically when the sampled data is arranged in the order of size, and the value of the mode switch point is determined for each mode. The method according to claim 1 or 5, The mode switching point is obtained through the ratio of the high level data and the low level data through the chip which is the minimum data unit of the slot because the ratio of the high level data group and the low level data group is different in each mode. 1xEV-DO Power Detection Method The method of claim 1, Determining the mode of 1xEV-DO using the obtained mode switch point includes determining a mode by comparing the value of the mode switch point obtained through the configuration ratio of the high level data and the low level data through the chip with a predetermined switch point value for each mode. 1xEV-DO power detection method in the RF power amplifier, characterized in that. An apparatus for detecting 1xEV-DO power in an RF power amplifier that amplifies and outputs input power, A power detector configured to measure input power, output power, and reflected power of the power amplifier to extract a DC level; A DC level amplifier configured to amplify a predetermined level of the DC level extracted by the power detector; An A / D converter converting the DC level amplified by the DC level amplifier into a digital value; A controller which samples the digital data converted by the A / D converter, obtains a mode switch point using the sampled data, determines a mode of an output signal, and compensates for an error in power according to the determined mode 1xEV-DO power detection device in the RF power amplifier comprising a. The method of claim 8, An RC low pass filter is configured in the DC level amplifier to remove noise and high frequency components while maintaining the shape of the output waveform of the power detector.

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