WO1992005631A1 - Method and arrangement for automatic gain control of a radio-frequency power amplifier - Google Patents
Method and arrangement for automatic gain control of a radio-frequency power amplifier Download PDFInfo
- Publication number
- WO1992005631A1 WO1992005631A1 PCT/FI1991/000292 FI9100292W WO9205631A1 WO 1992005631 A1 WO1992005631 A1 WO 1992005631A1 FI 9100292 W FI9100292 W FI 9100292W WO 9205631 A1 WO9205631 A1 WO 9205631A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- radio
- amplifier
- signal
- frequency
- arrangement
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 10
- 238000005070 sampling Methods 0.000 claims abstract description 13
- 230000001939 inductive effect Effects 0.000 claims description 3
- 239000003990 capacitor Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G3/00—Gain control in amplifiers or frequency changers
- H03G3/20—Automatic control
- H03G3/30—Automatic control in amplifiers having semiconductor devices
- H03G3/3036—Automatic control in amplifiers having semiconductor devices in high-frequency amplifiers or in frequency-changers
- H03G3/3042—Automatic control in amplifiers having semiconductor devices in high-frequency amplifiers or in frequency-changers in modulators, frequency-changers, transmitters or power amplifiers
Definitions
- the invention relates to a method and an arrangement for automatic gain control of a radio- frequency power amplifier.
- transmission-frequency signals from a modulator are usually amplified by a separate wide-band radio-frequency power amplifier before the signal is applied to an antenna.
- the object of the invention is to provide gain control for a radio-frequency power amplifier, by means of which the magnitude of the output signal of even a non-linear amplifier can be adjusted to a desired level without a long control loop. This is achieved by means of a method according to the invention for the automatic gain ' control of a radio-frequency power amplifier, which method is characterized in that the gain of the amplifier is adjusted by a control signal obtained by comparing samples taken from the input and output signals of the amplifier.
- the invention is also concerned with an arrangement for automatic gain control of a radio-fr ⁇ equency power amplifier, the arrangement comprising a first sampling means for generating a sample signal from the input signal of the radio-frequency amplifier; a second sampling means for generating a sample signal from the output signal of the radio-frequency amplifier; and means for comparing the sample signals with each other and for generating a control signal adjusting the gain of the radio-frequency amplifier on the basis of the comparison.
- the invention is based on the idea that the gain of the amplifier is monitored and adjusted con ⁇ tinuously on the basis of sample signals taken from the input and output signals of the amplifier in such a way that the ratio between the input and output levels of the amplifier, i.e. the gain of the amplifier, is maintained constant.
- the sampling of the input and output signals of the amplifier is preferably carried out by microstrip directional couplers or other similar means based on capacitive and/or inductive sampling, thus avoiding traditional measurement of gain by means of a series resistor measuring the collector current of the power transistor of the amplifier.
- the preferred embodiment of the invention shown in the figure comprises a radio-frequency amplifier 1, preferably a non-linear radio-frequency power amplifier biased to operate in class AB, for instance.
- the amplifier 1 comprises a radio-frequency signal input 10 to which a radio-frequency input signal RF IN to be amplified is applied e.g. from the transmitter itself when the amplifier 1 is a separate power amplifier, and a radio-frequency signal output 15 at which an amplified radio-frequency output signal RF OUT to be applied to a transmitting antenna is present.
- the signal input 10 of the amplifier 1 comprises a microstrip directional coupler 2 which generates a sample signal 11 proportional to the magnitude or level of the incoming signal, which sample signal is detected by a detector circuit 4 and filtered by a lowpass filter 5 before it is applied to an input 13 in a comparator circuit 8.
- the signal output 15 of the amplifier 1 com ⁇ prises a microstrip directional coupler 3 which generates from the output signal of the amplifier a sample signal 12 proportional to the magnitude or level of the output signal, and the sample signal is detected by a detector circuit 6 and filtered by a lowpass filter 7 before it is applied to another input 14 in the comparator 8.
- the comparator 8 super- vises the gain of the amplifier 1 by comparing the sample signals present at its inputs 13 and 14 with each other and/or with one or more predetermined reference values. On the basis of the comparison the comparator circuit 8 generates a power control signal 9 to be applied to the amplifier 1 so as to adjust the collector voltage of a power transistor forming a radio-frequency amplifier, stage in the amplifier 1 in order to maintain the total gain of the amplifier at a constant value.
- the comparator 8 may also generate an alarm signal 16 when the magnitudes of the compared sample signals change in such a way that they meet a pre ⁇ determined alarm criterion.
- the alarm criterion may be e.g. such that the alarm signal 16 is generated when the gain determined on the basis of the sample signals decreases below a predetermined reference value.
- the sampling means 2 and 3 are advantageous to realize by a microstrip directional coupler due to the simplicity of such couplers and the high reproducibility offered by the microstrip technology.
- the sample signals can be easily scaled already at the sampling stage for the comparison.
- the sampling means may be realized by any other directional coupler or other similar device effecting an inductive and/or capacitive coupling, such as a separate pick-up thread or pick-up capacitor.
- the detecting means 4 and 6 effecting the power detection are preferably half-wave rectifiers effected by means of a diode, and the filters 5 and 7 can be realized by any suitable lowpass filtering technique.
- the comparator circuit 8 can be realized by an operational amplifier coupled as a differential amplifier, which compares the signals present at the inputs 13 and 14 with each other, thus giving directly an output control signal proportional to the gain.
Landscapes
- Amplifiers (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FI904712A FI86350C (sv) | 1990-09-25 | 1990-09-25 | Förfarande och anordning för automatisk förstärkningsreglering i högfr ekvensförstärkaren |
FI904712 | 1990-09-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1992005631A1 true WO1992005631A1 (en) | 1992-04-02 |
Family
ID=8531112
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/FI1991/000292 WO1992005631A1 (en) | 1990-09-25 | 1991-09-23 | Method and arrangement for automatic gain control of a radio-frequency power amplifier |
Country Status (3)
Country | Link |
---|---|
AU (1) | AU8509391A (sv) |
FI (1) | FI86350C (sv) |
WO (1) | WO1992005631A1 (sv) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0632585A1 (fr) * | 1993-06-30 | 1995-01-04 | Alcatel Telspace | Système de commande de la polarisation d'un amplificateur |
EP0803973A1 (en) * | 1996-04-25 | 1997-10-29 | Lucent Technologies Inc. | Linear power amplifier with automatic gate/base bias control for optimum efficiency |
FR2810473A1 (fr) * | 2000-06-15 | 2001-12-21 | Sagem | Dispositif de production d'un signal radioelectrique module en phase et en amplitude et procede de production d'un tel signal |
WO2006043140A1 (en) * | 2004-10-22 | 2006-04-27 | Nokia Siemens Networks Oy | Method and apparatus for maintaining constant linearity for a power amplifier over varying load conditions |
Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2213099A (en) * | 1935-12-11 | 1940-08-27 | Rediffusion Ltd | Distortion indicator for electrical amplifying systems |
US3495179A (en) * | 1966-06-23 | 1970-02-10 | Hewlett Packard Co | Amplifier overload indicator |
US3833856A (en) * | 1973-11-15 | 1974-09-03 | Us Navy | Apparatus for testing an amplifier |
US4032853A (en) * | 1976-10-28 | 1977-06-28 | Hibbs Jr Eugene B | Overdrive detector for radio frequency amplifier |
US4048573A (en) * | 1976-10-15 | 1977-09-13 | Mcintosh Laboratory, Incorporated | Amplifier improvements for limiting clipping |
GB2081038A (en) * | 1980-07-25 | 1982-02-10 | Inst Francais Du Petrole | Devices for amplifying and sampling multiplexed signals |
EP0078130A2 (en) * | 1981-10-28 | 1983-05-04 | Cbs Inc | Automatic loudness controller |
EP0171843A2 (en) * | 1984-08-17 | 1986-02-19 | Philips Electronics Uk Limited | Bipolar transistor RF power amplifier |
US4574248A (en) * | 1984-05-07 | 1986-03-04 | Rockwell International Corporation | RF Power amplifier for use with VHF transceivers |
WO1987004305A1 (en) * | 1985-12-30 | 1987-07-16 | Hughes Aircraft Company | Traveling wave tube drive controller |
US4694258A (en) * | 1986-03-14 | 1987-09-15 | General Instrument Corporation | Method and system of enhancing performance of feedforward amplifiers |
EP0238286A2 (en) * | 1986-03-18 | 1987-09-23 | Nec Corporation | Automatic gain control apparatus |
-
1990
- 1990-09-25 FI FI904712A patent/FI86350C/sv not_active IP Right Cessation
-
1991
- 1991-09-23 WO PCT/FI1991/000292 patent/WO1992005631A1/en unknown
- 1991-09-23 AU AU85093/91A patent/AU8509391A/en not_active Abandoned
Patent Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2213099A (en) * | 1935-12-11 | 1940-08-27 | Rediffusion Ltd | Distortion indicator for electrical amplifying systems |
US3495179A (en) * | 1966-06-23 | 1970-02-10 | Hewlett Packard Co | Amplifier overload indicator |
US3833856A (en) * | 1973-11-15 | 1974-09-03 | Us Navy | Apparatus for testing an amplifier |
US4048573A (en) * | 1976-10-15 | 1977-09-13 | Mcintosh Laboratory, Incorporated | Amplifier improvements for limiting clipping |
US4032853A (en) * | 1976-10-28 | 1977-06-28 | Hibbs Jr Eugene B | Overdrive detector for radio frequency amplifier |
GB2081038A (en) * | 1980-07-25 | 1982-02-10 | Inst Francais Du Petrole | Devices for amplifying and sampling multiplexed signals |
EP0078130A2 (en) * | 1981-10-28 | 1983-05-04 | Cbs Inc | Automatic loudness controller |
US4574248A (en) * | 1984-05-07 | 1986-03-04 | Rockwell International Corporation | RF Power amplifier for use with VHF transceivers |
EP0171843A2 (en) * | 1984-08-17 | 1986-02-19 | Philips Electronics Uk Limited | Bipolar transistor RF power amplifier |
WO1987004305A1 (en) * | 1985-12-30 | 1987-07-16 | Hughes Aircraft Company | Traveling wave tube drive controller |
US4694258A (en) * | 1986-03-14 | 1987-09-15 | General Instrument Corporation | Method and system of enhancing performance of feedforward amplifiers |
EP0238286A2 (en) * | 1986-03-18 | 1987-09-23 | Nec Corporation | Automatic gain control apparatus |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0632585A1 (fr) * | 1993-06-30 | 1995-01-04 | Alcatel Telspace | Système de commande de la polarisation d'un amplificateur |
FR2708399A1 (fr) * | 1993-06-30 | 1995-02-03 | Alcatel Telspace | Système de commande de la polarisation d'un amplificateur. |
US5430410A (en) * | 1993-06-30 | 1995-07-04 | Alcatel N.V. | Amplifier bias control system |
EP0803973A1 (en) * | 1996-04-25 | 1997-10-29 | Lucent Technologies Inc. | Linear power amplifier with automatic gate/base bias control for optimum efficiency |
FR2810473A1 (fr) * | 2000-06-15 | 2001-12-21 | Sagem | Dispositif de production d'un signal radioelectrique module en phase et en amplitude et procede de production d'un tel signal |
WO2006043140A1 (en) * | 2004-10-22 | 2006-04-27 | Nokia Siemens Networks Oy | Method and apparatus for maintaining constant linearity for a power amplifier over varying load conditions |
US7190221B2 (en) | 2004-10-22 | 2007-03-13 | Nokia Corporation | Method and apparatus for maintaining constant linearity for a power amplifier over varying load conditions |
Also Published As
Publication number | Publication date |
---|---|
FI86350B (fi) | 1992-04-30 |
FI904712A (fi) | 1992-03-26 |
AU8509391A (en) | 1992-04-15 |
FI904712A0 (fi) | 1990-09-25 |
FI86350C (sv) | 1992-08-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5434537A (en) | Circuit for measuring the output power from an amplifier | |
EP0639890B1 (en) | Directional detector for power level control | |
CA1164054A (en) | Radio transmitter having an output power control circuit | |
KR0138224B1 (ko) | 무선 주파수 증폭기 바이어스 제어방법 및 장치 | |
US5208550A (en) | Radio-frequency power amplifier device | |
US5532646A (en) | High frequency power amplifier | |
US4574248A (en) | RF Power amplifier for use with VHF transceivers | |
US5892396A (en) | Method and apparatus for controlling gain of a power amplifier | |
WO2002056460A3 (en) | Apparatus and methods for monitoring and controlling power amplifier linearity using detected fundamental and harmonic components | |
KR920702081A (ko) | 자동 이득 제어 회로 | |
WO1992005631A1 (en) | Method and arrangement for automatic gain control of a radio-frequency power amplifier | |
US4156848A (en) | High dynamic range detector for indicating the quieting level of an FM receiver | |
US5003270A (en) | RF power-control circuit | |
EP1082810A1 (en) | A gain control circuit and method for providing gain control of a variable amplifier using a pilot signal | |
US4079325A (en) | Microwave frequency discriminator | |
US4952886A (en) | RF power-control circuit | |
JPH08503594A (ja) | 高周波電力増幅器の動作を制御する方法およびシステム | |
US5530405A (en) | Low consumption multi-stage amplifier, and a vehicle onboard signal receiver having such an amplifier | |
EP0939486A3 (en) | Filter circuit | |
FI85784C (sv) | Förfarande och anordning för övervakning av högfrekvensförstärkarens k ondition | |
US5374905A (en) | Phase locked loop motor control circuit for tuning cavity resonator | |
CA2058482C (en) | Baseband signal processing circuit for a radio communication apparatus | |
US6169808B1 (en) | Signal compressing circuit | |
CA2380829A1 (en) | Power detecting circuit and demodulator comprising the same | |
SU1494208A1 (ru) | Усилительное устройство с регулируемым коэффициентом усилени |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AU GB NO |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): AT BE CH DE DK ES FR GB GR IT LU NL SE |