A method for making a power amplifier support multi-power, a radio frequency module and a testing method

CROSS-REFERENCE TO RELATED APPLICATIONS

0001This application claims priority to Chinese Patent Publication No. <patcit id="pcit0001" dnum="CN1983851A"><text>CN1983851A, filed on June 16, 2006</text></patcit>, entitled "METHOD, RF MODULE AND TEST METHOD FOR ENABLING POWER AMPLIFIER TO SUPPORT MULTIPLE POWERS", commonly assigned herein for all purposes.

FIELD OF THE INVENTION

0002The present invention relates to a Radio Frequency (RF) technology, and more particular to a method, an RF module, and a test method for enabling a power amplifier to support multiple powers.

BACKGROUND

0003Currently, in a base station, an RF module receives the downlink data distributed by a baseband board. The downlink data is processed in the RF module, and becomes an RF signal. The processing to downlink data includes shaping filter, digital up-conversion, digital-to-analog conversion (DAC), amplification of Intermediate Frequency (IF) analog signals, and up-conversion of analog signals. The RF signal is then amplified by a power amplifier before being transmitted to an antenna.

0004In the prior art, the RF module includes a conversion module that converts a baseband board signal into an RF signal, a storage module, a control module, a power amplifier module, a power module, and an antenna linear device.

0005The conversion module that converts a baseband board signal into an RF signal converts the downlink data distributed by the baseband board into an RF signal. The storage module stores the manufacturing information about the RF module, such as the information about the hardware version; the control module reads and resolves the information about the hardware version stored in the storage module, and determines the power supported by the power amplifier module. The power amplifier module amplifies the received signal, and transmits the signal to an antenna through the antenna linear device. The power module supplies power to the power amplifier module, which outputs a fixed voltage to the power amplifier module, and ensures that the power amplifier module amplifies the signal based on the power supported by the power amplifier module.

0006When the RF module is manufactured, the production equipment writes the manufacturing information into the RF module. The information about the hardware version includes a byte indicating the power amplification capability of the module. The byte records the power supported by the RF module, for example, 20 W. When the RF module works, the control module of the RF module reads and resolves the byte to know the power amplification capability of the RF module. When the RF module transmits the signal, the maximum power is the maximum capability of power amplification.

0007Therefore, the power amplification capability of the RF module depends on the manufacturing information, which needs to be written precisely by the production equipment. Once the power amplification capability supported by the RF module is determined, the RF module can work with only the power amplifier module that supports the maximum power. In the RF module, the voltage provided to the power amplifier module is a fixed value. If the power amplifier modules which support different powers are used, these power amplifier modules may be burnt due to overlarge input voltages. In particular, if these power amplifier modules are improperly assembled during production, they are more likely to be burnt.

0008According to meet the requirements of different operators, the RF module of a base station needs to be supported by power amplifier modules with multiple powers. Therefore, the power amplifier modules with multiple powers needs to developed to meet the different application requirement. However, the power amplifier modules with multiple powers have different requirements on manufacturing, testing, and processes. Too many different types and numbers of the power amplification products reduce the productivity, and increase burden on the development and maintenance. <patcit id="pcit0002" dnum="US20050186923A1"><text>US2005/0186923A1</text></patcit> discloses Method and apparatus for improving power amplifier efficiency in wireless communication systems having high peak to average power ratios. A power management system and method for a wireless communication device generates an average desired transmit power signal based on at least one of a received signal strength indicator signal and a power control instruction signal from a base station. A power supply level adjustment signal is generated based on the data parameters of an outgoing data stream and at least one environmental information signal. A combination of the power supply level adjustment signal and the average desired transmit power or a gain control signal and an altered version of the power supply level adjustment signal is used to generate a variable power supply signal that is provided to an output amplifier block for sufficiently generating outgoing wireless device radio signals while reducing power loss in the output amplifier block. <patcit id="pcit0003" dnum="WO0048307A"><text>WO00/48307A</text></patcit> discloses HIGH-EFFICIENCY MODULATING RF AMPLIFIER. The present invention, generally speaking, provides for high-efficiency power control of a high-efficiency (e.g., hard-limiting or switch-mode) power amplifier in such a manner as to achieve a desired modulation. In one embodiment, the spread between a maximum frequency of the desired modulation and the operating frequency of a switch-mode DC-DC converter is reduced by following the switch-mode converter with an active linear regulator. The linear regulator is designed so as to control the operating voltage of the power amplifier with sufficient bandwidth to faithfully reproduce the desired amplitude modulation waveform. The linear regulator is further designed to reject variations on its input voltage even while the output voltage is changed in response to an applied control signal. This rejection will occur even though the variations on the input voltage are of commensurate or even lower frequency than that of the controlled output variation. Amplitude modulation may be achieved by directly or effectively varying the operating voltage on the power amplifier while simultaneously achieving high efficiency in the conversion of primary DC power to the amplitude modulated output signal. High efficiency is enhanced by allowing the switch-mode DC-to-DC converter to also vary its output voltage such that the voltage drop across the linear regulator is kept at a low and relatively constant level. Time-division multiple access (TDMA) bursting capability may be combined with efficient amplitude modulation, with control of these functions being combined. In addition, the variation of average output power level in accordance with commands from a communications system may also be combined within the same structure. <patcit id="pcit0004" dnum="US20060046668A1"><text>US2006/0046668A1</text></patcit> discloses Power consumption controlling apparatus for high frequency amplifier. A power consumption controlling apparatus controls power consumption of a high frequency amplifier to reduce the power consumption by adjusting a power supply voltage and a bias voltage of the high frequency amplifier which amplifies a high frequency transmitting signal. The power consumption controlling apparatus includes: a receiving circuit for receiving the high frequency transmitting signal amplified by the high frequency amplifier; an evaluating section for evaluating whether or not a receiving signal obtained from the receiving circuit satisfies a predetermined quality; and an adjusting section for adjusting the power supply voltage and the bias voltage in a range in which the receiving signal evaluated by the evaluating section satisfies the predetermined quality. <patcit id="pcit0005" dnum="US6141541A"><text>US-A-6141541</text></patcit> discloses Method, device, phone and base station for providing envelope-following for variable envelope radio frequency signals. A method (200) and device (100) provide an efficient linear power amplifier that generates a variable-envelope radio frequency RF signal. The method includes the steps of: A) using an efficient envelope-following unit to output a supply voltage in accordance with a variable envelope of an input baseband signal, wherein using the efficient envelope-following unit includes: 1) using a bandwidth-limiting mapping unit to determine a reference signal based on the baseband signal; and 2) using an envelope-tracking power converter to output a supply voltage, responsive to the reference signal, to the linear RF power amplifier; B) providing an RF input signal with amplitude and phase information to a linear RF power amplifier; and C) using the linear RF power amplifier to output a power-efficient amplified variable-envelope RF signal with substantially a same amplitude and phase information as the RF input signal. <patcit id="pcit0006" dnum="US4866714A"><text>US-A-4866714</text></patcit> discloses Personal computer-based dynamic burn-in system. An installation for the dynamic burn-in testing of a plurality of digital circuits, and/or microcomputer-controlled circuits, mounted in a burn-in chamber for testing includes a personal computer; power supply for the digital circuits, and a bilateral line of communication between the PC computer and each of the digital circuits; the PC computer interrogating separately, and at will, any of the digital circuits as to their status and capability of changing status while retrieving any indication of a critical testing condition from any digital circuit, to determine a failure-free burn-in time. <patcit id="pcit0007" dnum="EP0590651A"><text>EP-A-0590651</text></patcit> discloses Dynamic random access memory device having power supply system appropriately biasing switching transistors and storage capacitors in burn-in testing process. A power supply system incorporated in a dynamic random access memory device distributes a step-down power voltage and a boosted voltage to a sense amplifier unit and a word line driver for allowing switching transistors of the memory cells to transfer the step-down voltage level to the storage capacitor without any voltage drop in read-out and write-in modes, and the switching transistors and the storage capacitors are subjected to inspections through a burn-in testing process before delivery from the manufacturing factory so as to actualize potential failure; ; however, either switching transistors or storage capacitors are insufficiently stressed in the burn-in testing process, and the power supply system changes the ratio of the boosted voltage to the step-down power voltage between the read-out and write-in modes and the burn-in testing process so that the switching transistors and the storage capacitors are sufficiently stressed.

SUMMARY

0009Accordingly, an embodiment of the present invention provides a method for enabling a power amplifier to support multiple powers, and an RF module capable of enabling a power amplifier to support application requirements for different transmit powers in a system. Another embodiment of the present invention also provides a test method for determining a corresponding relationship between a transmit power and a power amplifier voltage.

0010The method for enabling a power amplifier to support multiple powers includes: receiving RF parameters delivered by a baseband board, and calculating a transmit power according to the RF parameters; determining a power amplifier voltage according to the transmit power and a determined corresponding relationship between the transmit power and the power amplifier voltage; and adjusting a supply voltage of the power amplifier according to the determined power amplifier voltage so as to adjust an output power of the power amplifier; wherein the determined corresponding relationship between the transmit power and the power amplifier voltage is obtained through: calibrating a power amplifier module (203) and an RF module; storing a corresponding relationship between the transmit power and the power amplifier voltage in the RF module; performing, by a production equipment, index test on the RF module according to the power amplifier voltage corresponding to the transmit power after an aging treatment of the RF module; determining whether the index test satisfies a specification, adjusting the power amplifier voltage corresponding to the transmit power according to result of the determination; and updating the corresponding relationship between the transmit power and the power amplifier voltage by using the adjusted power amplifier voltage.

0011The system includes a RF module. The RF module includes a conversion module that converts a baseband board signal into an RF signal, an antenna linear device, and a power amplifier module. The RF module further includes an adjustable power module; a storage module (208), adapted to store RF parameters delivered by a baseband board and corresponding relationship between transmit power and power amplifier voltage; and a power control module (201), adapted to calculate the transmit power according to the RF parameters stored in the storage module (208), determine the power amplifier voltage according to the transmit power and the corresponding relationship between the transmit power and the power amplifier voltage, and adjust an output voltage of the adjustable power module (202) according to the determined power amplifier voltage; and the system further includes: means for calibrating the power amplifier module and the RF module; means for storing a corresponding relationship between the transmit power and the power amplifier voltage in the RF module; a production equipment, adapted to perform index test on the RF module according to the power amplifier voltage corresponding to the transmit power after an aging treatment of the RF module; means for determining whether the index test satisfies a specification; means for adjusting the power amplifier voltage corresponding to the transmit power according to result of the determination; and means for updating the corresponding relationship between the transmit power and the power amplifier voltage by using the adjusted power amplifier voltage.

0012As disclosed by the above technical schemes, in the embodiments of the present invention, the corresponding relationship between the transmit power and the power amplifier voltage is determined by the test method of the present invention. Then, the determined corresponding relationship is stored in the RF module. The power module is set to be an adjustable power module. The RF module calculates the transmit power according to the received RF parameters delivered by the baseband board, determines the power amplifier voltage according to the calculated transmit power and the corresponding relationship between the transmit power and the power amplifier voltage stored in the RF module, and adjusts the output power of the adjustable power module according to the determined power amplifier voltage, so as to adjust the output power of the power amplifier module, i.e., the transmit power of the RF module. Thus, the power amplifier can support multiple powers.

BRIEF DESCRIPTION OF THE DRAWING(S)

0013<figref idref="f0001">Figure 1</figref> is a flow chart for determining a corresponding relationship between the transmit power and the power amplifier voltage according to an embodiment of the present invention;

0014<figref idref="f0002">Figure 2</figref> is a structural view of an exemplary embodiment of an RF module of the present invention; and

0015<figref idref="f0003">Figure 3</figref> is a flow chart of an exemplary embodiment of a method for enabling a power amplifier to support multiple powers of the present invention.

DETAILED DESCRIPTION

0016In order to make the objectives, technical schemes, and beneficial effects of the present invention more understandable, the present invention is described in more detail below by reference to the accompanying drawings and embodiments.

0017In an embodiment of the present invention, the corresponding relationship between the transmit power and the power amplifier voltage is first determined, and then stored in the RF module, and the power module in the RF module is replaced by an adjustable power module. The RF module receives the RF parameters delivered by the baseband board, calculates the transmit power according to the received RF parameters, and determines the power amplifier voltage according to the calculated transmit power and the corresponding relationship between the transmit power and the power amplifier voltage stored in the RF module. The supply voltage of the power amplifier is adjusted according to the determined voltage, so as to adjust the output power of the power amplifier.

0018In this embodiment, the method of the RF module determining the power amplifier voltage according to the calculated transmit power and the corresponding relationship between the transmit power and the power amplifier voltage stored in the RF module specifically includes: the RF module queries the list in which the corresponding relationship between the transmit power and the power amplifier voltage is stored and reads the power amplifier voltage corresponding to the calculated transmit power. If the query and reading succeeds, the read power amplifier voltage is determined to be the power amplifier voltage; and if the query and reading fails, the preset default value is determined to be the power amplifier voltage.

0019<figref idref="f0001">Figure 1</figref> is a flow chart for determining a corresponding relationship between the transmit power and the power amplifier voltage according to an embodiment of the present invention, which includes the following steps.

0020Step 101: Production equipment debugs the power amplifier module and the RF module under the configuration of the tested RF module, and the obtained corresponding relationship between RF power and standard operating voltage of the power amplifier is written into the storage module of the RF module, namely , the different RF powers and the standard operating voltages of the power amplifier corresponding to the RF powers are written into the storage module of the RF module.

0021For the convenience of use, a table of voltage parameters of the power amplifier can be generated, and the corresponding relationship between the transmit power and the standard operating voltage of the power amplifier obtained after calibrating can be written into the table of voltage parameters of the power amplifier.

0022Step 102: An aging treatment is performed on the RF module.

0023Step 103: The production equipment performs index tests on the RF module after the aging treatment under the standard operating voltages, stored in the RF module, of the power amplifier corresponding to different transmit powers. The index tests include a spectrum index test and an efficiency index test.

0024In Step 104, the production equipment determines whether the spectrum index and the efficiency index tested under all the standard operating voltages of the power amplifier satisfy relevant specifications. If the two indexes satisfy the specifications, Step 105 is performed. If the spectrum index tested under some standard operating voltages of the power amplifier does not satisfy the specifications, Step 106 is performed. If the efficiency index tested at some standard operating voltages of the power amplifier does not satisfy the specifications, Step 107 is performed.

0025Step 105: The corresponding relationship between the RF power and the standard operating voltage of the power amplifier stored in the storage module of the RF module is kept unchanged.

0026Step 106: The production equipment finely adjusts the standard operating voltages under which the tested spectrum index does not satisfy the specifications to lower values, until the spectrum index satisfies the specifications, and then Step 108 is performed.

0027Step 107: The production equipment finely adjusts the standard operating voltages of the power amplifier under which the tested efficiency index does not satisfy the specifications to higher values, until the efficiency index satisfies the specifications.

0028Step 108: The production equipment updates the corresponding relationship between the transmit power and the power amplifier voltage stored in the RF module according to the power amplifier voltages obtained through the adjustment in Step 106 or 107.

0029In order to improve the production efficiency, the written and adjusted corresponding relationship between the RF power and the power amplifier voltage needs to be maintained and updated periodically. The corresponding relationship between the RF power and the power amplifier voltage of the RF modules produced in a batch has a data standard, which exhibits the trend of the corresponding relationship between the RF power and the power amplifier voltage. Normally, the corresponding relationship between the RF power and power amplifier voltage of the RF modules produced in a production batch is basically the same, and a batch lasts several months. Therefore, if the corresponding relationship between the RF power and the power amplifier voltage of the RF modules produced in the batch is updated in time, the RF modules produced later will need less adjustment, which improves the production efficiency.

0030For the convenience of use, a table of voltage parameters of the power amplifier can be generated, and the corresponding relationship between the RF power and the power amplifier voltage can be written into the table of voltage parameters of the power amplifier. The table of voltage parameters of the power amplifier is maintained and updated periodically.

0031<figref idref="f0002">Figure 2</figref> is a structural view of a preferred embodiment of the RF module that enables a power amplifier to support multiple powers of the present invention. Referring to <figref idref="f0002">Figure 2</figref>, the RF module includes a power control module 201, a power module 202, a power amplifier module 203, a conversion module 204 that converts a baseband board signal into an RF signal, and an antenna linear device 205.

0032The conversion module 204 that converts a baseband signal into an RF signal is adapted to convert downlink data delivered by the baseband board into an RF signal. The antenna linear device 205 is adapted to transmit the RF signal amplified by the power amplifier module to the antenna.

0033The power module 202 is an adjustable power module, and includes a power control portion 206, a power amplifier power source 207, and a storage module 208. In this embodiment, the power control portion 206 can be an adjustable chip.

0034The storage module 208 is connected to the power control module 201 through a bus. The power control portion 206 of the power module 202 is connected to the power control module 201 through the bus. The power amplifier power source 207 is connected to the power control portion 206 through a power cable. The power amplifier power source 207 is connected to the power amplifier module 203, and supplies power to the power amplifier module 203.

0035The storage module 208 stores a parameter carrier n, a power level Ln per carrier, a switch value of the power-saving mode, the table of voltage parameters written into the RF module by the production equipment and information about the power module 202 including coefficients for calculating a voltage control parameter, which are received by the RF module from the baseband board.

0036The power control portion 206 of the power module 202 is adapted to set the voltage control parameter output from the power control module 201 to the output voltage of the power amplifier power source 207.

0037The functions of the power control module 201 include:

00381) obtaining the switch value of the power-saving mode from the storage module 208 to determine whether to enable the power-saving mode, that is, whether to select the power amplifier that supports multiple functions. The switch value of the power-saving mode is a hexadecimal software tag. Normally, the value 0 indicates that the power-saving mode is disabled, and the value 1 indicates that the power-saving mode is enabled.

00392) determining whether it is necessary to calculate the transmit power based on the RF parameters stored in the storage module 208 according to the switch value of the power-saving mode obtained from the storage module 208, and determining the mode of reading the power amplifier voltage in the table of voltage parameters of the power amplifier. If the reading succeeds, the power amplifier voltage, for example, Vout is set to the read voltage; otherwise, the power amplifier voltage Vout is set to the default value.

00403) reading the values of the coefficients, the coefficients for calculating a voltage control parameter K and B, for calculating the voltage control parameter from the storage module 208 of the power module. If the reading fails, the coefficients for calculating a voltage control parameter K and B are set to the default values. Then, the voltage control parameter is calculated with the formula Vc = K x Vout + B based on the determined values of the coefficients for calculating a voltage control parameter K and B.

00414) outputing the obtained voltage control parameter to the power control portion 206, and set to be the output voltage of the power amplifier power source 207 through the power control portion 206, so as to control the output voltage of the power control power source.

0042In this embodiment, the storage module 208 is disposed in the power module 202. In actual applications, the storage module 208 may also be disposed outside the power module 202, or a part of the storage module 208 is disposed in the power module 202, and the other part is disposed outside the power module 202.

0043<figref idref="f0003">Figure 3</figref> is a flow chart of a preferred embodiment of a method for enabling a power amplifier to support multiple powers of the present invention. Referring to <figref idref="f0003">Figure 3</figref>, this method uses the method shown in <figref idref="f0001">Figure. 1</figref>. The table of voltage parameters of the power amplifier in which the corresponding relationship between the RF power and the power amplifier voltage is written is stored in the storage module of the RF module in advance. The method includes the following steps.

0044Step 301: The RF module receives the RF parameters delivered by the baseband board, including the parameter carrier n, the power level Ln per carrier, and the switch value of the power-saving mode, and stores the parameters in the storage module thereof.

0045Step 302: The power control module obtains the switch value of the power-saving mode from the storage module, and determines whether to enable the power-saving mode.

0046The switch value of the power-saving mode is a hexadecimal software tag delivered by the baseband board. Normally, the value 0 indicates that the power-saving mode is disabled, and the value 1 indicates that the power-saving mode is enabled. If the power-saving mode is disabled, Step 307 is performed; otherwise, Step 303 is performed.

0047Step 303: The power control module calculates the transmit power according to the RF parameters stored in the storage module. In this embodiment, the RF parameters include the carrier number and the carrier power level, and the process of calculating the transmit power is to calculate the transmit power level.

0048Provided that the transmit power level is L, which can be calculated with the formula L = -100 x log(10^(L1 / (-100)) + ... + 10^(Ln/(-100)). Here, the values of L1 to Ln range from 0 to 100.

0049The prerequisite for the transmit power level to represent the transmit power is that the power amplifier voltages corresponding to the transmit power levels are stored during calibrating, that is, the different transmit power levels and the corresponding power amplifier voltages are stored in the table of voltage parameters of the power amplifier.

0050Step 304: The power control module queries a corresponding power amplifier voltage in the table of voltage parameters of the power amplifier stored in the storage module according to the obtained transmit power level. If the query succeeds, Step 305 is performed; otherwise, Step 306 is performed.

0051Step 305: The power control module sets the power amplifier voltage Vout to the queried power amplifier voltage. Then, Step 308 is performed.

0052Step 306: The power control module sets the power amplifier voltage Vout to the default value. Then, Step 308 is performed.

0053Step 307: The power control module reads the first power amplifier voltage in the table of voltage parameters of the power amplifier stored in the storage module, and sets the power amplifier voltage Vout to the value.

0054Steps 308 and 309, the power control module reads the values of the coefficients for calculating a voltage control parameter K and B from the storage module. If the reading succeeds, Step 311 is performed; otherwise, Step 310 is performed.

0055Step 310: The power control module sets the coefficients for calculating a voltage control parameter K and B to the default values.

0056The storage module is normally an E2PROM, which is a physical component. The E2PROM may become invalid due to the limitation on reading/writing times, or may have an exception because the bus is busy, which result in the failure of the power control module reading the E2PROM. Therefore, in order to ensure the continuity of the implementation process of the power control module, the default values of K and B are set in the power control module. When the power control module fails to read K and B, the default values are used in the calculation.

0057Step 311: The power control module calculates the voltage control parameter Vc based on the values of K and B determined in Steps 308 and 309, the power amplifier voltage Vout set in Step 305, 306, or 307, and the formula Vc = K x Vout + B, and outputs the voltage control parameter Vc to the power control portion of the power module.

0058Step 312: The power control portion of the power module sets the value of the voltage control parameter Vc obtained in Step 311 to the output voltage of the power amplifier power source, so as to adjust the voltage of the power amplifier power source.

0059After the voltage of the power amplifier power source is adjusted, according to the formula Power = Input voltage X Input current, in the situation that the input current of the power amplifier module remains unchanged, the power of the power amplifier module can be adjusted by adjusting the input voltage of the power amplifier module.

0060It is known from the above embodiments that the RF module and the power amplifier module are calibrated, the corresponding relationship between the transmit power and the power amplifier voltage is obtained after the aging treatment and index tests, and the corresponding relationship is stored in the RF module. Meanwhile, the power control module is disposed in the RF module, and the power module in the RF module is set to an adjustable power module, such that the RF module can adjust the supply voltage of the power amplifier module according to the obtained transmit power and the stored power amplifier voltages corresponding to different transmit powers. Further, the power amplifier can support multiple powers.

0061In addition, the test method provided in an embodiment of the present invention can update the corresponding relationship between the transmit power and the power amplifier voltage stored in the RF module in real time if necessary.

0062In a word, the method and the RF provided in the embodiments of the present invention can enable a power amplifier to support multiple powers and satisfy the different application requirements by adjusting the output voltage that the power module supplies to the power amplifier module according to the different application requirements. Thus, it is unnecessary to produce and maintain power amplifiers with different transmit powers. The power amplifier can be used more flexibly, the maintenance cost of the power amplifier is reduced, and the production and use of the power amplifier becomes easier.

0063Though the objectives, technical schemes, and beneficial effects of the present invention have been disclosed above by exemplary embodiments, the present invention is not limited to these. Any modifications, equivalent substitutions, and variations made within the scope of the present invention fall within the scope of the present invention.