JP2012080298A - Nonlinear distortion compensation amplification device and nonlinear distortion compensation method - Google Patents
Nonlinear distortion compensation amplification device and nonlinear distortion compensation method Download PDFInfo
- Publication number
- JP2012080298A JP2012080298A JP2010223297A JP2010223297A JP2012080298A JP 2012080298 A JP2012080298 A JP 2012080298A JP 2010223297 A JP2010223297 A JP 2010223297A JP 2010223297 A JP2010223297 A JP 2010223297A JP 2012080298 A JP2012080298 A JP 2012080298A
- Authority
- JP
- Japan
- Prior art keywords
- signal
- frequency characteristic
- feedback circuit
- distortion compensation
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Amplifiers (AREA)
- Transmitters (AREA)
Abstract
Description
本発明は、無線通信システム送信機の非線形歪補償に係り、特にフィードバック回路の周波数特性編差を補償する非線形歪補償増幅装置及びそのフィードバック回路周波数特性偏差補償方法に関する。 The present invention relates to non-linear distortion compensation of a radio communication system transmitter, and more particularly to a non-linear distortion compensation amplifying apparatus and a feedback circuit frequency characteristic deviation compensating method for compensating for frequency characteristic variation of a feedback circuit.
無線通信システムの送信機を構成する高周波増幅器における非線形歪特性への対応、及び非線形歪特性に起因する電力利用効率の低さ及び小型化のため、非線形歪補償増幅装置が用いられる。非線形歪補償増幅装置として適応型プリディストーション補償装置が知られている。 A non-linear distortion compensation amplifying apparatus is used in order to cope with non-linear distortion characteristics in a high-frequency amplifier constituting a transmitter of a wireless communication system, and to reduce power use efficiency and size due to the non-linear distortion characteristics. An adaptive predistortion compensation device is known as a nonlinear distortion compensation amplification device.
図４は従来の非線形歪補償増幅装置の回路構成を示す図である。演算部４１、ＤＡＣ４２、直交変調部４３、高周波増幅器４４、方向性結合器４５、アンテナ４６、ＦＢ回路（フィードバック回路）４７で構成する。ＦＢ回路４７はＡＤＣ５１、バンドパスフィルタ５２、増幅器５３、振幅等化器５４、ミキサ５５で構成する。 FIG. 4 is a diagram showing a circuit configuration of a conventional nonlinear distortion compensation amplifying apparatus. The calculation unit 41, DAC 42, quadrature modulation unit 43, high frequency amplifier 44, directional coupler 45, antenna 46, and FB circuit (feedback circuit) 47 are included. The FB circuit 47 includes an ADC 51, a band pass filter 52, an amplifier 53, an amplitude equalizer 54, and a mixer 55.
入力ベースバンド信号が演算部４１より出力され、ディジタルアナログ変換器（ＤＡＣ４２）によりアナログ信号に変換後、直交変調部４３で無線周波数帯域の高周波信号に直交変調される。この直交変調波は、必要な送信電力まで高周波増幅器４４により増幅後、方向性結合器４５を介して無線周波数の送信信号としてアンテナ４６より送出される。 An input baseband signal is output from the calculation unit 41, converted into an analog signal by a digital-analog converter (DAC 42), and then orthogonally modulated by a quadrature modulation unit 43 into a high-frequency signal in a radio frequency band. The quadrature modulated wave is amplified by the high frequency amplifier 44 to a required transmission power, and then transmitted from the antenna 46 as a radio frequency transmission signal via the directional coupler 45.
高周波増幅器４４の入出力電力特性の非線形性により、送信信号に非線形歪が生じる。 Non-linear distortion occurs in the transmission signal due to the non-linearity of the input / output power characteristics of the high-frequency amplifier 44.
この非線形歪補償のため、方向性結合器４５により抽出された無線周波数の送信信号の一部をＦＢ回路４７により演算部４１にフィードバックして適応的に非線形歪の補償処理が行われる。 For this nonlinear distortion compensation, a part of the radio frequency transmission signal extracted by the directional coupler 45 is fed back to the arithmetic unit 41 by the FB circuit 47 to adaptively compensate the nonlinear distortion.
ＦＢ回路４７では、ミキサ５５により低周波信号にダウンコンバートされた信号は増幅器により所定の電力まで増幅され、バンドパスフィルタ５２により不要周波数信号の除去後、アナログディジタル変換器（ＡＤＣ５１）によりディジタル信号に変換され、演算部４１にフィードバックされる。 In the FB circuit 47, the signal down-converted to the low frequency signal by the mixer 55 is amplified to a predetermined power by the amplifier, and after the unnecessary frequency signal is removed by the band pass filter 52, it is converted into a digital signal by the analog-digital converter (ADC 51). The result is converted and fed back to the calculation unit 41.
演算部４１では、このフィードバックされた信号から歪補償成分を抽出し、送信波のベースバンド信号に歪補償成分を付加して送出する。この動作により、高周波増幅器等で発生する非線形歪に対して適応し、安定した歪補償制御が行われる。このような適応型非線形歪補償回路は環境の変化に対して適応し、安定した特性を得ることができる。適応型非線形歪補償回路については例えば、特許文献１に記載されている。 The computing unit 41 extracts a distortion compensation component from the fed back signal, adds the distortion compensation component to the baseband signal of the transmission wave, and sends it out. By this operation, stable distortion compensation control is performed by adapting to nonlinear distortion generated in a high-frequency amplifier or the like. Such an adaptive nonlinear distortion compensation circuit can adapt to environmental changes and obtain stable characteristics. An adaptive nonlinear distortion compensation circuit is described in Patent Document 1, for example.
また、高周波増幅器と適応非線形歪補償部の間にイコライザを備え、帯域外輻射電力が小さくなるフィルタ係数を算出して補正する方法が知られている（例えば、特許文献２）。 Also, a method is known in which an equalizer is provided between the high-frequency amplifier and the adaptive nonlinear distortion compensator, and a filter coefficient that reduces the out-of-band radiation power is calculated and corrected (for example, Patent Document 2).
なお、以下では、場合により、演算部４１からアンテナ４６の送信経路をフォワード系、また、フォワード系の信号を主信号と表現し、また、方向性結合器４５から分岐した信号の経路をフィードバック系（場合により、フィードバック回路、ＦＢ回路）と表現する。 In the following, the transmission path from the calculation unit 41 to the antenna 46 is represented as a forward system, the forward system signal is represented as a main signal, and the signal path branched from the directional coupler 45 is represented as a feedback system. (Depending on the case, it is expressed as a feedback circuit or an FB circuit).
従来の非線形歪補償増幅装置のＦＢ回路４７を構成するアナログフィルタ（バンドパスフィルタ５２）、増幅器５３、振幅等化器５４、ＡＤＣ５１は通常周波数特性を持っており、この周波数特性の編差による誤った歪成分を検出して歪補償を行うため、送信信号の非線形歪補償を悪化させる要因となっている。 The analog filter (bandpass filter 52), the amplifier 53, the amplitude equalizer 54, and the ADC 51 constituting the FB circuit 47 of the conventional nonlinear distortion compensation amplifying apparatus have normal frequency characteristics. Therefore, distortion compensation is performed by detecting a distortion component, which is a factor that deteriorates nonlinear distortion compensation of a transmission signal.
具体的にはＦＢ回路４７の周波数特性編差により、演算部は誤った歪成分の検出を行い、歪補償後の主信号の歪特性は、例えば、高域、あるいは低域の何れか片側の歪が悪化する。 Specifically, due to the frequency characteristic variation of the FB circuit 47, the arithmetic unit detects an erroneous distortion component, and the distortion characteristic of the main signal after distortion compensation is, for example, one of the high frequency and the low frequency. Distortion worsens.
この周波数特性の補正として、特許文献１では、フィードバック回路に補正フィルタを備え、ループ全体の周波数特性の逆特性を補正して周波数特性の改善を行う方法を開示している。 As correction of this frequency characteristic, Patent Document 1 discloses a method of improving a frequency characteristic by providing a correction filter in a feedback circuit and correcting an inverse characteristic of the frequency characteristic of the entire loop.
この場合、非線形歪成分を検出するためのＦＢ回路４７の周波数特性編差を含めて補償を行っているため、フィードバック回路に周波数特性の編差が存在する場合にはアンテナから送信する送信信号の歪特性を悪化させる歪補償を行う結果となる。 In this case, since the compensation including the frequency characteristic variation of the FB circuit 47 for detecting the nonlinear distortion component is performed, if there is a frequency characteristic variation in the feedback circuit, the transmission signal transmitted from the antenna As a result, distortion compensation that deteriorates the distortion characteristics is performed.
即ち、適応型非線形歪補償回路においては、予めフィードバック回路の周波数特性の編差を確認しておき、この周波数特性の編差を補正して歪補償を行うこととなる。
本発明は非線形歪補償装置の歪補償をフィードバック回路の周波数特性偏差による影響を排除して主信号系で生じる非線形歪の歪補償を行うことができる非線形歪補償増幅装置、及びフィードバック回路周波数特性偏差補償方法の提供を目的とする。
In other words, in the adaptive nonlinear distortion compensation circuit, the difference in frequency characteristics of the feedback circuit is confirmed in advance, and the distortion compensation is performed by correcting the difference in frequency characteristics.
The present invention relates to a nonlinear distortion compensation amplifying apparatus and a feedback circuit frequency characteristic deviation which can perform distortion compensation of nonlinear distortion generated in the main signal system by eliminating the influence of the frequency characteristic deviation of the feedback circuit. The purpose is to provide a compensation method.
上記問題解決のため、無線通信システムの送信機の試験時に試験信号を発生し、フォワード系の高周波増幅前に、該試験信号をフィードバック回路と検波回路に分岐して送信し、フィードバック回路の出力よりフィードバック回路の周波数特性の算出と、検波回路の出力より検波回路の周波数特性と、を算出し、２つの周波数特性偏差の差分より前記フィードバック回路の周波数特性偏差を算出し、算出したフィードバック回路の周波数特性偏差の逆特性を前記主信号系の送信信号に歪補償信号として加えて非線形歪補償を行う。 In order to solve the above problem, a test signal is generated at the time of testing the transmitter of the wireless communication system, and the test signal is branched and transmitted to the feedback circuit and the detection circuit before the high frequency amplification of the forward system. Calculate the frequency characteristic of the feedback circuit, calculate the frequency characteristic of the detection circuit from the output of the detection circuit, calculate the frequency characteristic deviation of the feedback circuit from the difference between the two frequency characteristic deviations, and calculate the frequency of the feedback circuit Nonlinear distortion compensation is performed by adding a reverse characteristic of the characteristic deviation to the transmission signal of the main signal system as a distortion compensation signal.
本発明によれば、非線形歪補償装置の歪補償をフィードバック回路の周波数特性偏差による影響を排除して主信号系で生じる非線形歪の歪補償を行うことができる。 According to the present invention, it is possible to perform distortion compensation of nonlinear distortion generated in the main signal system by eliminating the influence of the frequency characteristic deviation of the feedback circuit.
（実施例１）
図１は本発明の一実施形態の非線形歪補償増幅装置のブロック構成を示す図である。演算部１、適応非線形歪補償部２、ＤＡＣ３、直交変調部４、分波器１ ５、高周波増幅器６、方向性結合器７、アンテナ８、ＦＢ回路９、分波器２ １０、切替器１１、検波器系回路１２で構成する。
Example 1
FIG. 1 is a diagram showing a block configuration of a nonlinear distortion compensation amplifying apparatus according to an embodiment of the present invention. Operation unit 1, adaptive nonlinear distortion compensation unit 2, DAC 3, quadrature modulation unit 4, demultiplexer 15, high frequency amplifier 6, directional coupler 7, antenna 8, FB circuit 9, demultiplexer 2 10, switch 11 The detector system circuit 12 is configured.
演算部１は、イコライザ（ＦＩＲフィルタ）２１、信号切替部２２、試験信号発生器２３、帯域外輻射電力測定・フィルタ係数算出部２４、ＦＢ回路周波数特性算出部２５、分岐部２６、ＦＢ回路周波数特性算出部２７、検波器系回路周波数特性算出部２８、切替信号発生部２９で構成する。 The calculation unit 1 includes an equalizer (FIR filter) 21, a signal switching unit 22, a test signal generator 23, an out-of-band radiation power measurement / filter coefficient calculation unit 24, an FB circuit frequency characteristic calculation unit 25, a branching unit 26, and an FB circuit frequency. The characteristic calculation unit 27, the detector circuit frequency characteristic calculation unit 28, and the switching signal generation unit 29 are configured.
ＦＢ回路９はＡＤＣ１ ３０、バンドパスフィルタ３１、増幅器３２、ミキサ３３で構成し、検波器系回路１２は、ＡＤＣ２ ３４、検波器３５で構成する。次に回路動作について説明する。 The FB circuit 9 includes an ADC 1 30, a band pass filter 31, an amplifier 32, and a mixer 33, and the detector system circuit 12 includes an ADC 2 34 and a detector 35. Next, circuit operation will be described.
フォワード回路では演算部１からの信号（試験時は試験信号、運用時は入力ベースバンド信号）はＤＡＣ３によりアナログ信号に変換された後、直交変調部４で無線周波数帯域の高周波信号に直交変調される。 In the forward circuit, the signal from the arithmetic unit 1 (test signal at the time of test, input baseband signal at the time of operation) is converted to an analog signal by the DAC 3 and then orthogonally modulated by the quadrature modulation unit 4 to a high-frequency signal in the radio frequency band. The
運用時、この直交変調波は分波器１ ５を経由して、高周波増幅器６により必要な送信電力まで増幅された後、方向性結合器７を介して無線周波数の送信信号としてアンテナ８より送出される。試験時、分波器１ ５は直交変調部４から受信した送信信号を切替器１１に分波する。 In operation, this quadrature modulated wave is amplified to the required transmission power by the high frequency amplifier 6 via the demultiplexer 15, and then transmitted from the antenna 8 as a radio frequency transmission signal via the directional coupler 7. Is done. During the test, the demultiplexer 15 demultiplexes the transmission signal received from the quadrature modulation unit 4 to the switch 11.
切替器１１は演算部１からの切替制御信号（例えば、試験時「ＯＮ」。運用時「ＯＦＦ」）により、試験時は分波器１ ５からの試験信号を受信し、分波器２ １０に送信する。運用時は方向性結合器７からの送信信号を受信して分波器２ １０に送信する。 The switch 11 receives a test signal from the duplexer 15 at the time of the test by the switching control signal (for example, “ON” at the time of test and “OFF” at the time of operation) from the calculation unit 1, and the duplexer 2 10. Send to. During operation, the transmission signal from the directional coupler 7 is received and transmitted to the duplexer 210.
分波器２ １０は切替器１１からの信号を受信する。試験時は、ＦＢ回路９と検波器系回路１２に試験信号を1対１に分岐して送信する。運用時は切替器１１からの送信信号をＦＢ回路９に送信する。 The duplexer 210 receives the signal from the switch 11. At the time of the test, the test signal is branched and transmitted to the FB circuit 9 and the detector system circuit 12 on a one-to-one basis. During operation, a transmission signal from the switch 11 is transmitted to the FB circuit 9.
ＦＢ回路９において、受信した信号はミキサ３３により低周波信号にダウンコンバートされ、増幅器３２により所定の電力まで増幅された後、バンドパスフィルタ３１により不要周波数成分を除去してＡＤＣ１ ３０によりディジタル信号に変換され、演算部１にフィードバックされる。 In the FB circuit 9, the received signal is down-converted to a low frequency signal by the mixer 33, amplified to a predetermined power by the amplifier 32, unnecessary frequency components are removed by the band pass filter 31, and converted to a digital signal by the ADC 1 30. It is converted and fed back to the calculation unit 1.
試験時、検波器系回路１２では、検波器３５で、受信した試験信号の電力が直流電圧に変換され、ＡＤＣ２ ３４によりディジタル信号に変換されて演算部１に送られる。 At the time of the test, in the detector system circuit 12, the power of the received test signal is converted into a DC voltage by the detector 35, converted into a digital signal by the ADC 234, and sent to the computing unit 1.
次に演算部１の動作を試験時と運用時に分けて説明する。
１）試験時
切替信号発生器２９より、試験制御信号を発生し、試験信号発生器２３より試験信号をフォワード回路に送信する。試験信号は例えば、変調波、あるいはＣＷ（Ｃｏｎｔｉｎｕｏｕｓ Ｗａｖｅ）信号である。フォワード回路を経由してＦＢ回路９、検波器系回路１２にフィードバックされた信号の処理について説明する。
Next, the operation of the calculation unit 1 will be described separately during the test and during the operation.
1) During a test A test control signal is generated from the switching signal generator 29, and a test signal is transmitted from the test signal generator 23 to the forward circuit. The test signal is, for example, a modulated wave or a CW (Continuous Wave) signal. Processing of signals fed back to the FB circuit 9 and the detector system circuit 12 via the forward circuit will be described.
ＦＢ回路９から受信した試験信号は分岐部２６を経由して、ＦＢ回路周波数特性算出部２５に入力される。ＦＢ回路周波数特性算出部２５でフィードバック回路の周波数特性を算出する。一方、検波器系回路１２から受信した試験信号は検波器系回路周波数特性算出部２８に送信される。 The test signal received from the FB circuit 9 is input to the FB circuit frequency characteristic calculation unit 25 via the branch unit 26. The FB circuit frequency characteristic calculator 25 calculates the frequency characteristic of the feedback circuit. On the other hand, the test signal received from the detector system circuit 12 is transmitted to the detector system circuit frequency characteristic calculator 28.
ＦＢ回路周波数特性算出部２５、検波器系回路周波数特性算出部２８で各々周波数特性が算出され、ＦＢ回路周波数特性遍差算出部２７で、検波器系回路周波数特性を基準特性として、２つの経路の周波数特性の差がＦＢ回路の周波数特性遍差として算出される。図２で２つの経路の周波数特性の差がＦＢ回路の周波数特性遍差であることを図的に説明する。
２）運用時
ＦＢ回路９から受信した信号は分岐部２６を経由して帯域外輻射電力測定・フィルタ係数算出部２５と、適応非線形歪補償部２と、に送信される。
The FB circuit frequency characteristic calculation unit 25 and the detector system circuit frequency characteristic calculation unit 28 calculate frequency characteristics, respectively. The FB circuit frequency characteristic unequal calculation unit 27 uses the detector system circuit frequency characteristic as a reference characteristic, and provides two paths. The frequency characteristic difference is calculated as the frequency characteristic universal difference of the FB circuit. FIG. 2 graphically explains that the difference between the frequency characteristics of the two paths is the FB circuit frequency characteristic difference.
2) During Operation The signal received from the FB circuit 9 is transmitted to the out-of-band radiation power measurement / filter coefficient calculation unit 25 and the adaptive nonlinear distortion compensation unit 2 via the branch unit 26.
帯域外輻射電力測定・フィルタ係数算出部２４では、帯域外輻射電力を測定し、該輻射電力が小さくなるようにイコライザ（ＦＩＲフィルタ）の係数を決め、さらにこのフィルタ係数を、試験時ＦＢ回路周波数特性遍差算出部２７で算出したフィードバック回路の周波数特性遍差の逆特性で補正してイコライザのフィルタ係数の適応処理を行う。 The out-of-band radiated power measurement / filter coefficient calculation unit 24 measures the out-of-band radiated power, determines the coefficient of the equalizer (FIR filter) so that the radiated power becomes small, and further determines this filter coefficient as the FB circuit frequency during the test. An equalizer filter coefficient adaptive process is performed by correcting the inverse characteristic of the frequency characteristic of the feedback circuit calculated by the characteristic difference calculation unit 27.
一方、適応非線形歪補償部２に入力された信号は、入力信号との差が小さくなるよう適応処理が行われる。適応非線形歪補償部２の詳細動作については説明を省略する。 On the other hand, the signal input to the adaptive nonlinear distortion compensator 2 is subjected to adaptive processing so that the difference from the input signal is reduced. The detailed operation of the adaptive nonlinear distortion compensator 2 will not be described.
また、フォワード回路（ＤＡＣ３、直交変調部４、分波器１ ５、高周波増幅器６）、フィードバック回路の何れかに障害が発生した場合、フィードバック回路の周波数特性算出、検波回路の周波数特性算出により障害箇所の切り分けができる。例えば、
ア．障害発生後、フォワード回路へ試験信号を送信し、ＦＢ回路周波数特性算出結果として、所定の電力が検出出来ない場合に、検波器系回路周波数特性算出結果を確認し、所定の電力が検出出来る場合、ＦＢ回路９の障害と判断出来る。
イ．障害発生後、フォワード回路へ試験信号を送信し、ＦＢ回路周波数特性算出結果および検波器系回路周波数特性算出結果共に所定の電力が検出出来ない場合は、フォワード回路の障害と判断出来る。また、切替器１１を切替えすることでフォワード回路内のＤＡＣ３、直交変調部４、または高周波増幅器６の障害かを切り分けすることが出来る。切替器11を分波器1からの信号を選択した場合に所定の電力を検出出来、方向性結合器からの信号を選択した場合に所定の電力を検出出来ない場合は、高周波増幅器６の障害と判断出来る。
Further, when a failure occurs in any of the forward circuit (DAC 3, quadrature modulation unit 4, demultiplexer 15 and high frequency amplifier 6) and the feedback circuit, the failure is caused by calculating the frequency characteristic of the feedback circuit and calculating the frequency characteristic of the detection circuit. It is possible to separate the points. For example,
A. When a test signal is transmitted to the forward circuit after a failure has occurred and the predetermined power cannot be detected as the FB circuit frequency characteristic calculation result, the detector circuit frequency characteristic calculation result is confirmed and the predetermined power can be detected Therefore, it can be determined that the FB circuit 9 is faulty.
A. After a failure occurs, a test signal is transmitted to the forward circuit, and when the predetermined power cannot be detected in both the FB circuit frequency characteristic calculation result and the detector system circuit frequency characteristic calculation result, it can be determined that the failure is in the forward circuit. Further, by switching the switch 11, it is possible to determine whether the failure is in the DAC 3, the quadrature modulation unit 4, or the high-frequency amplifier 6 in the forward circuit. If the switch 11 can detect the predetermined power when the signal from the demultiplexer 1 is selected, and cannot detect the predetermined power when the signal from the directional coupler is selected, then the high frequency amplifier 6 is faulty. It can be judged.
逆に切替器１１を分波器１からの信号を選択した場合に所定の電力を検出出来ない場合は、ＤＡＣ３、直交変調部４の障害と判断出来る。 On the contrary, when the switch 11 selects a signal from the duplexer 1, if the predetermined power cannot be detected, it can be determined that the DAC 3 and the quadrature modulation unit 4 are faulty.
なお、試験時に動作させた、検波器系回路１２、ＦＢ回路周波数特性偏差算出部２５等の運用時には動作不要なブロックは基本的に動作、あるいは処理を止めることも可能である。 It should be noted that the blocks that do not require operation during operation of the detector system circuit 12, the FB circuit frequency characteristic deviation calculation unit 25, etc., which are operated during the test, can basically stop operating or processing.
図２は本発明のフィードバック回路の周波数特性の振幅編差算出説明を示す図である。フィードバック回路と検波器系回路の周波数特性を基にフィードバック回路で生じる周波数特性編差の算出について説明している。
１）演算部の試験信号発生部で試験信号を発生し、フォワード回路に出力する。
発生する試験信号は送信帯域内にΔｆ間隔の変調波またはＣＷ信号であり、また、信号のレベルは運用時のフィードバック回路の所定のレベルに合うように設定し、ｆ１からｆＮのＮ箇所の信号（図では８か所）を1波毎、順次フォワード回路へ送信する。
２）試験信号が各々の経路を経由することにより周波数特性の遍差が発生する。
送信された試験信号がフォワード回路のＤＡＣ３、直交変調部４、分波器１ ５、切替器１１、分波器２ １０を経由することにより、経路での周波数特性により振幅遍差が発生する。
３）検波器系回路を経由した試験信号の特性を算出する。
検波器を経由した試験信号（ＡＤＣ２の出力）の電力を演算部で算出する。Ｐ１（ｆｉ）とする。
４）フィードバック回路を経由した試験信号の特性を算出する。
ミキサ３３、増幅器３２、バンドパスフィルタ３１を経由した試験信号（ＡＤＣ１の出力）の電力を算出する。Ｐ２（ｆｉ）とする。
５）フィードバック回路の周波数特性遍差を算出する。
検波器系回路出力の電力検出結果Ｐ１（ｆ１）〜Ｐ１（ｆＮ）を基準信号として、フィードバック回路出力の電力算出結果と比較し、式１で示す周波数振幅遍差を算出する。２）で述べたフォワード回路の特性偏差はＦＢ回路、検波器回路に共通なので、この周波数振幅遍差がフィードバック回路の周波数遍差である。ここで、基準特性となる検波器３６は送信帯域の周波数特性の偏差がないこと、また、電力変動に対して一次変化をすることが好ましい。または、特性を演算部１で補完することが出来ることが好ましい。
FIG. 2 is a diagram showing an explanation of the calculation of the amplitude difference between the frequency characteristics of the feedback circuit of the present invention. The calculation of the frequency characteristic variation generated in the feedback circuit based on the frequency characteristics of the feedback circuit and the detector system circuit is described.
1) A test signal is generated by the test signal generator of the arithmetic unit and output to the forward circuit.
The generated test signal is a modulated wave or CW signal having an interval of Δf within the transmission band, and the level of the signal is set so as to match a predetermined level of the feedback circuit during operation, and N points from f 1 to f N (8 locations in the figure) are sequentially transmitted to the forward circuit for each wave.
2) When the test signal passes through each path, an uneven frequency characteristic occurs.
The transmitted test signal passes through the DAC 3 of the forward circuit, the quadrature modulation unit 4, the duplexer 15, the switch 11, and the duplexer 2 10, thereby generating an amplitude difference due to the frequency characteristics in the path.
3) Calculate the characteristics of the test signal that passes through the detector circuit.
The power of the test signal (ADC2 output) that passes through the detector is calculated by the calculation unit. Let P 1 (f i ).
4) Calculate the characteristics of the test signal via the feedback circuit.
The power of the test signal (output of ADC 1) that passes through the mixer 33, the amplifier 32, and the band pass filter 31 is calculated. Let P 2 (f i ).
5) Calculate the frequency characteristic homogeneity of the feedback circuit.
The power detection result P 1 (f 1 ) to P 1 (f N ) of the detector system circuit output is used as a reference signal, compared with the power calculation result of the feedback circuit output, and the frequency amplitude uniformity shown in Equation 1 is calculated. Since the characteristic deviation of the forward circuit described in 2) is common to the FB circuit and the detector circuit, this frequency amplitude difference is the frequency difference of the feedback circuit. Here, it is preferable that the detector 36 serving as the reference characteristic has no deviation in the frequency characteristic of the transmission band, and undergoes a primary change with respect to the power fluctuation. Alternatively, it is preferable that the characteristics can be complemented by the calculation unit 1.
また、本方法は、高周波増幅器６を経由しない試験信号でフィードバック回路の周波数特性遍差を算出できる。即ち、高周波増幅器６は、試験時に送信する変調波またはＣＷ信号を増幅した場合、信号を歪ませたり、また不要波を発生する可能性があるが、本方法はその影響を受けず動作出来る特徴がある。 In addition, according to the present method, the frequency characteristic inhomogeneity of the feedback circuit can be calculated from a test signal that does not pass through the high frequency amplifier 6. That is, when the modulated wave or CW signal transmitted during the test is amplified, the high-frequency amplifier 6 may distort the signal or generate an unnecessary wave. There is.
図３は本発明の一実施形態のフィードバック回路の周波数特性遍差算出手順例を示す図である。図２で示したフィードバック回路の周波数特性遍差算出説明を基にフィードバック回路で発生する周波数特性編差算出の手順例を示している。
Ｓ１：試験信号として以下を設定する。ここで、「ｉ］＝１とする。
ア．初期値：ｆ１
イ．周波数間隔：Δｆ
ウ．設定周波数個数：Ｎ
Ｓ２：周波数ｆｉの試験信号をフォワード回路に送信する。なお、試験信号のレベルは運用時でのフィードバック回路の所定のレベルに設定し、切換制御信号を「オン」として、分波器１の信号を切替器に出力する。
Ｓ３：試験信号フィードバック回路出力の信号電力Ｐ１（ｆｉ）、検波器出力の信号電力Ｐ２（ｆｉ）を算出する。
Ｓ４：両電力の差分を算出する。
FIG. 3 is a diagram showing an example of a frequency characteristic universal difference calculation procedure of the feedback circuit according to the embodiment of the present invention. FIG. 3 shows an example of a procedure for calculating frequency characteristic variation generated in the feedback circuit based on the description of calculating the frequency characteristic universal difference of the feedback circuit shown in FIG.
S1: The following is set as a test signal. Here, “i” = 1.
A. Initial value: f 1
A. Frequency interval: Δf
C. Number of set frequencies: N
S2: transmitting a test signal of a frequency f i to the forward circuit. Note that the level of the test signal is set to a predetermined level of the feedback circuit at the time of operation, the switching control signal is set to “ON”, and the signal of the duplexer 1 is output to the switch.
S3: signal power P 1 (f i) of the test signal feedback circuit output, calculates detector output signal power P 2 a (f i).
S4: The difference between both electric powers is calculated.
Ｓ５：ｉ＝ｉ+１
Ｓ６：ｉ＞Ｎであるか、確認し、ｉ＞ＮならばＳ８に移り、そうでない場合はＳ７を経由してＳ２に戻る。
Ｓ７：ｆｉ＝ｆｉ+Δｆ、ｉ＝ｉ+１
Ｓ８：フィードバック回路の周波数特性振幅偏差（ΔＰ（ｆｉ）＝Ｐ２（ｆｉ）−Ｐ１（ｆｉ）ｉ＝１〜Ｎ）の逆特性を等化器に加え、フィードバック回路の周波数特性遍差を補償する。
S5: i = i + 1
S6: Check if i> N. If i> N, go to S8, otherwise return to S2 via S7.
S7: f i = f i + Δf, i = i + 1
S8: Frequency characteristic amplitude deviation of feedback circuit (ΔP (f i ) = P 2 (f i ) −P 1 (f i ) i = 1 to N) is added to the equalizer, and the frequency characteristic of the feedback circuit is added. Compensate for the inhomogeneity.
１ 演算部
２ 適応非線形歪補償部
３ ディジタルアナログ変換器（ＤＡＣ）
４ 直交変調部
５ 分波器１
６ 高周波増幅器
７ 方向性結合器
８ アンテナ
９ ＦＢ回路
１０ 分波器２
１１ 切替器
１２ 検波器系回路
２１ イコライザ
２２ 信号切替部
２３ 試験信号発生器
２４ 帯域外輻射電力測定・フィルタ係数算出部
２５ ＦＢ回路周波数特性算出部
２６ 分岐部
２７ ＦＢ回路周波数特性遍差算出部
２８ 検波系回路周波数特性算出部
２９ 切替信号発生器
３０ アナログディジタル変換器（ＡＤＣ１）
３１ バンドパスフィルタ
３２ 増幅器
３３ ミキサ
３４ アナログディジタル変換器（ＡＤＣ２）
３５ 検波器
４１ 演算部（従来ブロック図）
４２ ディジタルアナログ変換器（ＤＡＣ）（従来ブロック図）
４３ 直交変調部（従来ブロック図）
４４ 高周波増幅器（従来ブロック図）
４５ 方向性結合器（従来ブロック図）
４６ アンテナ（従来ブロック図）
４７ ＦＢ回路（従来ブロック図）
５１ アナログディジタル変換器（ＡＤＣ）（従来ブロック図）
５２ バンドパスフィルタ（従来ブロック図）
５３ 増幅器（従来ブロック図）
５４ 振幅等化器（従来ブロック図）
５５ ミキサ（従来ブロック図）
DESCRIPTION OF SYMBOLS 1 Computation part 2 Adaptive nonlinear distortion compensation part 3 Digital analog converter (DAC)
4 Quadrature modulation unit 5 Branching filter 1
6 High-frequency amplifier 7 Directional coupler 8 Antenna 9 FB circuit 10 Branching filter 2
DESCRIPTION OF SYMBOLS 11 Switcher 12 Detector system circuit 21 Equalizer 22 Signal switching part 23 Test signal generator 24 Out-of-band radiation power measurement and filter coefficient calculation part 25 FB circuit frequency characteristic calculation part 26 Branch part 27 FB circuit frequency characteristic inequality difference calculation part 28 Detection system circuit frequency characteristic calculation unit 29 Switching signal generator 30 Analog to digital converter (ADC1)
31 Band pass filter 32 Amplifier 33 Mixer 34 Analog to digital converter (ADC2)
35 Detector 41 Operation unit (conventional block diagram)
42 Digital-to-analog converter (DAC) (conventional block diagram)
43 Quadrature modulator (conventional block diagram)
44 High-frequency amplifier (conventional block diagram)
45 Directional coupler (conventional block diagram)
46 Antenna (conventional block diagram)
47 FB circuit (conventional block diagram)
51 Analog to Digital Converter (ADC) (Conventional Block Diagram)
52 Bandpass filter (conventional block diagram)
53 Amplifier (Conventional block diagram)
54 Amplitude equalizer (conventional block diagram)
55 Mixer (conventional block diagram)
Claims (3)
試験時に試験信号を発生する手段と、
前記無線周波数の送信信号を増幅前に分岐する第１の分岐手段と、
該増幅前に分岐した分岐送信信号と増幅後の無線周波数の送信信号のいずれかを切替制御信号により切り替える切替手段と、
前記試験時、第１の分岐手段により、無線周波数の試験信号を前記切替手段に分岐し、前記分岐した分岐試験信号をフィードバック回路と検波回路に分岐する第２の分岐手段と、
前記分岐した前記フィードバック回路の出力より前記フィードバック回路の周波数特性を算出するフィードバック回路周波数特性算出手段と、前記分岐した前記検波回路の出力より前記検波回路の周波数特性を算出する検波回路周波数特性算出手段と、前記フィードバック回路周波数特性算出手段で算出されたフィードバック回路の周波数特性と、前記検波回路周波数特性算出手段で算出された周波数特性と、の差より前記フィードバック回路の周波数特性偏差を算出する手段と、
前記算出されたフィードバック回路周波数特性偏差の逆特性を運用時に前記主信号系の送信信号に歪補償信号として加える歪補償演算手段と、
を備えたことを特徴とする非線形歪補償増幅装置。 A part of the transmission signal is branched from the main signal system of a wireless communication system that modulates and amplifies the input signal to output a radio frequency transmission signal, and a distortion compensation signal is added to the input transmission signal based on the fed back signal. In addition, in a non-linear distortion compensator that compensates for distortion of the radio frequency transmission signal,
Means for generating a test signal during testing;
First branching means for branching the radio frequency transmission signal before amplification;
Switching means for switching one of the branch transmission signal branched before the amplification and the transmission signal of the radio frequency after amplification by a switching control signal;
At the time of the test, a first branching means branches a radio frequency test signal to the switching means, and a second branching means for branching the branched branch test signal to a feedback circuit and a detection circuit;
Feedback circuit frequency characteristic calculation means for calculating the frequency characteristic of the feedback circuit from the output of the branched feedback circuit, and detection circuit frequency characteristic calculation means for calculating the frequency characteristic of the detection circuit from the output of the branched detection circuit. And means for calculating the frequency characteristic deviation of the feedback circuit from the difference between the frequency characteristic of the feedback circuit calculated by the feedback circuit frequency characteristic calculation means and the frequency characteristic calculated by the detection circuit frequency characteristic calculation means; ,
Distortion compensation calculation means for adding the inverse characteristic of the calculated feedback circuit frequency characteristic deviation as a distortion compensation signal to the transmission signal of the main signal system during operation;
A non-linear distortion compensation amplifying apparatus comprising:
試験時に試験信号を発生し、
前記発生した試験信号をフォワード系の前記増幅前にフィードバック回路と検波回路に分岐して送信し、
前記フィードバック回路の出力よりフィードバック回路周波数特性を算出し、
前記検波回路の出力より前記検波回路周波数特性を算出し、
前記算出したフィードバック回路周波数特性と、検波回路周波数特性と、の差より前記フィードバック回路の周波数特性偏差を算出し、
前記算出されたフィードバック回路周波数特性偏差の逆特性を運用時に前記主信号系の送信信号に歪補償信号として加えて非線形歪補償を行うことを特徴とする非線形歪補償装置の非線形歪補償方法。 A part of the transmission signal is branched from the main signal system of a wireless communication system that modulates and amplifies the input signal to output a radio frequency transmission signal, and a distortion compensation signal is added to the input transmission signal based on the fed back signal. In addition, a nonlinear distortion compensation method for a nonlinear distortion compensator that compensates for distortion of the transmission signal of the radio frequency,
Generate a test signal during the test,
The generated test signal is branched and transmitted to a feedback circuit and a detection circuit before the amplification of the forward system,
Calculate feedback circuit frequency characteristics from the output of the feedback circuit,
Calculate the detection circuit frequency characteristic from the output of the detection circuit,
The frequency characteristic deviation of the feedback circuit is calculated from the difference between the calculated feedback circuit frequency characteristic and the detection circuit frequency characteristic,
A nonlinear distortion compensation method for a nonlinear distortion compensation apparatus, wherein nonlinear distortion compensation is performed by adding an inverse characteristic of the calculated feedback circuit frequency characteristic deviation to a transmission signal of the main signal system as a distortion compensation signal during operation.
前記フィードバック回路の経路、あるいは前記検波回路の経路から算出する電力を判断して、前記非線形歪補償装置の障害箇所を推定することを特徴とする請求項２記載の非線形歪補償装置の非線形歪補償方法。
The nonlinear distortion compensation method for a nonlinear distortion compensation apparatus according to claim 2,
3. The nonlinear distortion compensation of the nonlinear distortion compensator according to claim 2, wherein the failure location of the nonlinear distortion compensator is estimated by judging the power calculated from the path of the feedback circuit or the path of the detector circuit. Method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2010223297A JP5464112B2 (en) | 2010-09-30 | 2010-09-30 | Nonlinear distortion compensation amplifying apparatus and nonlinear distortion compensation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2010223297A JP5464112B2 (en) | 2010-09-30 | 2010-09-30 | Nonlinear distortion compensation amplifying apparatus and nonlinear distortion compensation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2012080298A true JP2012080298A (en) | 2012-04-19 |
| JP5464112B2 JP5464112B2 (en) | 2014-04-09 |
Family
ID=46240043
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2010223297A Expired - Fee Related JP5464112B2 (en) | 2010-09-30 | 2010-09-30 | Nonlinear distortion compensation amplifying apparatus and nonlinear distortion compensation method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP5464112B2 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002077285A (en) * | 2000-08-31 | 2002-03-15 | Hitachi Kokusai Electric Inc | Transmiter |
| JP2003298362A (en) * | 2002-03-29 | 2003-10-17 | Fujitsu Ltd | Distortion compensation device |
| JP2004128833A (en) * | 2002-10-02 | 2004-04-22 | Fujitsu Ltd | Distortion compensator with multiple equalizer filter |
| JP2008306456A (en) * | 2007-06-07 | 2008-12-18 | Fujitsu Ltd | Radio transmission apparatus |
| JP2009246655A (en) * | 2008-03-31 | 2009-10-22 | Fujitsu Ltd | Non-linear distortion compensation apparatus, and frequency characteristic deviation compensation method thereof |
-
2010
- 2010-09-30 JP JP2010223297A patent/JP5464112B2/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002077285A (en) * | 2000-08-31 | 2002-03-15 | Hitachi Kokusai Electric Inc | Transmiter |
| JP2003298362A (en) * | 2002-03-29 | 2003-10-17 | Fujitsu Ltd | Distortion compensation device |
| JP2004128833A (en) * | 2002-10-02 | 2004-04-22 | Fujitsu Ltd | Distortion compensator with multiple equalizer filter |
| JP2008306456A (en) * | 2007-06-07 | 2008-12-18 | Fujitsu Ltd | Radio transmission apparatus |
| JP2009246655A (en) * | 2008-03-31 | 2009-10-22 | Fujitsu Ltd | Non-linear distortion compensation apparatus, and frequency characteristic deviation compensation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP5464112B2 (en) | 2014-04-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5113871B2 (en) | Power series digital predistorter and control method thereof | |
| KR101011748B1 (en) | Internal calibration system for a radio frequency rf transmitter | |
| KR20090020659A (en) | Distortion compensator apparatus, amplifier apparatus, transmitter, and method of compensating distortion | |
| JP2005142881A (en) | Distortion compensating amplifier | |
| JP2013214826A (en) | Radio apparatus, distortion compensation method and distortion compensation program | |
| KR101613012B1 (en) | Amplification apparatus | |
| JPWO2015045709A1 (en) | Signal transmission device, distortion compensation device, and signal transmission method | |
| JP2010258597A (en) | Apparatus for distortion compensation of power amplifier, and method of detecting failure in the same | |
| KR20100069454A (en) | Method and apparatus for enhancing performance of a doherty power amplifier in a communication system | |
| US9263994B2 (en) | Amplifying device, distortion compensating device, and amplifying method | |
| JPWO2011001576A1 (en) | Transmission circuit and communication device | |
| JP2009284232A (en) | Distortion compensation device and distortion compensation method | |
| JP5464112B2 (en) | Nonlinear distortion compensation amplifying apparatus and nonlinear distortion compensation method | |
| JP4784777B2 (en) | Predistortion distortion compensation device | |
| US9369092B2 (en) | Feed-forward amplifier device and method thereof | |
| JP2009246655A (en) | Non-linear distortion compensation apparatus, and frequency characteristic deviation compensation method thereof | |
| US8269572B2 (en) | Reducing the distortion of applied modulation | |
| JP4939281B2 (en) | Amplifier | |
| US20090111398A1 (en) | Transmitter and transmission method | |
| JP2006262156A (en) | Transmission apparatus and strain compensation method for transmission amplifier | |
| JP2012175573A (en) | Microwave transmission device | |
| JP6645428B2 (en) | Transmitter, transmission system and transmission method | |
| JP2005150814A (en) | Method and apparatus of compensating non-linear distortion | |
| JP2007142537A (en) | Parallel operation system and method for transmission amplifier | |
| JP2005236715A (en) | Distortion compensating circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20130702 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20131217 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20131224 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20140106 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| LAPS | Cancellation because of no payment of annual fees |