AU747958B2 - Radio frequency (RF) detection circuit - Google Patents
Radio frequency (RF) detection circuit Download PDFInfo
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- AU747958B2 AU747958B2 AU37953/00A AU3795300A AU747958B2 AU 747958 B2 AU747958 B2 AU 747958B2 AU 37953/00 A AU37953/00 A AU 37953/00A AU 3795300 A AU3795300 A AU 3795300A AU 747958 B2 AU747958 B2 AU 747958B2
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- Prior art keywords
- signal
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- radio frequency
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Classifications
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G3/00—Gain control in amplifiers or frequency changers without distortion of the input signal
- 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
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03D—DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
- H03D1/00—Demodulation of amplitude-modulated oscillations
- H03D1/08—Demodulation of amplitude-modulated oscillations by means of non-linear two-pole elements
- H03D1/10—Demodulation of amplitude-modulated oscillations by means of non-linear two-pole elements of diodes
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G3/00—Gain control in amplifiers or frequency changers without distortion of the input signal
- 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
Description
S&F Ref: 510783
AUSTRALIA
PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT
ORIGINAL
Name and Address of Applicant: Actual Inventor(s): Address for Service: NEC Corporation 7-1, Shiba Minato-ku Tokyo Japan Noriyuki Fujita Spruson Ferguson St Martins Tower 31 Market Street Sydney NSW 2000 Radio Frequency (RF) Detection Circuit Invention Title: The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5845c RADIO FREQUENCY (RF) DETECTION CIRCUIT BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The invention relates to a radio frequency detection circuit, and more particularly to a circuit used for detecting a transmitted signal in an auto power control (APC) circuit in a mobile communicator such as a cellular phone.
DESCRIPTION OF THE RELATED ART 10 Fig. 1 is a circuit diagram of a conventional RF detection circuit.
As illustrated in Fig. 1, the conventional RF detection circuit is comprised of a quadrature modulator 5 receiving IF signal and IQ signal, modulating those signals, and transmitting a single output signal, an interstage filter 16 receiving the output signal from the quadrature modulator 5, filtering the 15 output signal, and transmitting the filtered signal, a power amplifier 4 receiving the filtered signal from the interstage filter 16, amplifying the signal and transmitting an output signal, a directional coupler 24 receiving the output signal from the power amplifier 4 and branching the received output signal into two first signals, a detection diode 21 receiving one of the first signals from the directional coupler 24, detecting the received first signal, and transmitting an output signal, a buffer amplifier 19 receiving the output signal from the detection diode 21, amplifying the received output signal, and transmitting a signal, an adding amplifier 18 receiving the signal at a positive terminal from the buffer amplifier 19, and grounded at a negative terminal through a third resistor 27, and a comparison circuit 17 receiving both an output signal transmitted from the adding amplifier 18 and a control signal transmitted from a controller (not illustrated), comparing those signals to each other, and transmitting a signal indicative of comparison, to the quadrature modulator 5, as a feed-back signal.
A first resistor 38 is electrically connected at one end to the directional coupler 24 and grounded at the other end.
A first capacitor 36 is electrically connected in series between the directional coupler 24 and the detection diode 21.
A choke coil 34 is electrically connected at one end to a node between the first capacitor 36 and the detection diode 21, and electrically connected at the other end to a voltage source V
B
A second resistor 31 is electrically connected to a node between the detection diode 21 and the buffer amplifier 19, and grounded at the other end.
A second capacitor 30 is electrically connected at one end in 10 parallel with the second resistor 31, and grounded at the other end.
A fourth resistor 28 is electrically connected in series between the buffer amplifier 19 and the positive terminal of the adding amplifier 18.
~A fifth resistor 26 is electrically connected between the negative terminal and an output port of the adding amplifier 18.
15 As is readily understood, the conventional RF detection circuit •..."detects a signal by means of the single detection diode 21.
As a result, the conventional RF detection circuit could provide linearity characteristic only in the range of detection characteristic of the detection diode 21. That is, the conventional RF detection circuit could control signal power only in a dynamic range of about 25 dB or smaller.
However, a future device such as W-CDMA (Wideband-CDMA) will be required to carry out signal power control in a wider range, for instance, in a range of 50 dB or greater. Thus, the dynamic range in the conventional RF detection circuit is completely insufficient. Accordingly, it is necessary to widen dynamic range of detection characteristic in a RF detection circuit.
For instance, Japanese Unexamined Patent Publication No. 4- 40105 has suggested a linearity amplifying circuit.
Japanese Patent Publication No. 7-71054 has suggested a circuit for controlling signal transmission output.
-3- Japanese Unexamined Patent Publication No. 5-22061 has suggested an output power detection circuit.
Japanese Unexamined Patent Publication No. 7-297645 has suggested a detection circuit.
However, the circuits suggested in the above-mentioned Publications are all designed to include a single detection diode. Accordingly, these circuits are also accompanied with the problem that dynamic range in which signal power control is carried out is small for a future device.
In view of the above-mentioned problem, a need exists to provide a RF detection circuit which is capable of carrying out signal power control in a wider dynamic range than that of the conventional RF detection circuit.
SUMMARY OF THE INVENTION According to an aspect of the present invention, there is provided a radio frequency detection circuit [I:\DayLib\LIBQ]01 I 12.doc:edg including a modulator receiving first and second signals, and transmitting an output signal, a directional coupler receiving the output signal from the modulator, and dividing the thus received output signal into two first signals, a distributor receiving one of the two first signals from the directional coupler, and dividing the thus received first signal into N second signals wherein N is an integer equal to or greater than 2, first to N-th diodes each receiving one of the N second signals from the distributor, and transmitting a first to N-th output signal, an adder adding the first to N-th output signals to one another, and transmitting a sum signal, and a comparison circuit receiving the sum signal 10 and a control signal, comparing the sum signal to the control signal, and transmitting a feed-back signal indicative of comparison, to the modulator.
It is preferable that the radio frequency detection circuit further *includes first to N-th buffer amplifiers each electrically connected in series between the first to N-th diodes and the adder 15 It is preferable that the radio frequency detection circuit further includes first to N-th capacitors each electrically connected in series between the distributor and the first to N-th diodes.
In another aspect of the present invention, there is provided a method of detecting radio frequency, including the steps of modulating first and second signals, and transmitting an output signal, dividing the output signal into N first signals wherein N is an integer equal to or greater than 2, (c) detecting the N first signals, and resultingly transmitting N second signals, (d) adding the N second signals to one another, and transmitting a sum signal, and comparing the sum signal to a control signal, and transmitting a feed-back signal indicative of comparison, the feed-back signal being fed back to the step In still another aspect of the present invention, there is provided a radio frequency circuit to be used in a mobile transceiver, including a controller transmitting a control signal, a modem transmitting first and second signals, a modulator receiving the first and second signals, and transmitting an output signal, a directional coupler receiving the output signal from the modulator, and dividing the thus receiving output signal into two first signals, a distributor receiving one of the two first signals from the directional coupler, and dividing the thus received first signal into N second signals wherein N is an integer equal to or greater than 2, (f) first to N-th diodes each receiving one of the N second signals from the distributor, and transmitting a first to N-th output signal, an adder adding the first to N-th output signals to one another, and transmitting a sum signal, and a comparison circuit receiving the sum signal and the control signal, comparing the sum signal to the control signal, and transmitting a feed-back signal indicative of comparison, to the modulator.
According to another aspect of the present invention, there is provided a method of detecting radio frequency, comprising the steps of: modulating first and second signals, and transmitting an output signal; dividing said output signal into N first signals wherein N is an integer •equal to or greater than 2; S Is detecting said N first signals, and resultingly transmitting N second signals; adding said N second signals to one another, and transmitting a sum S-signal; and comparing said sum signal to a control signal, and transmitting a feed- 20 back signal indicative of comparison, said feed-back signal being fed back to said step According to yet another aspect of the present invention, there is provided a radio frequency circuit to be used in a mobile transceiver, comprising: a controller transmitting a control signal; a modem transmitting first and second signals; a modulator receiving said first and second signals, and transmitting an output signal; a directional coupler receiving said output signal from said modulator, and dividing the thus received output signal into two first signals; a distributor receiving one of said two first signals from said directional coupler, and dividing the thus received first signal into N second signals wherein N is an integer equal to or greater than 3; first to N-th diodes each receiving one of said N second signals from said distributor, and transmitting a first to N-th output signal; [I:\DayLib\LIBQ]01 I 12.doc:edg an adder adding said first to N-th output signals to one another, and transmitting a sum signal; and a comparison circuit receiving said sum signal and said control signal, comparing said sum signal to said control signal, and transmitting a feed-back signal indicative of comparison, to said modulator.
Possible advantages obtained by embodiments of the present invention will be described hereinafter.
In accordance with embodiments of the present invention, a RF detection circuit could have a higher dynamic range for signal power control than that of the conventional RF detection circuit.
In accordance with embodiments of the present invention, two or more detection diodes having different ranges of a voltage which the diodes can detect are operated in parallel, and outputs of those diodes are added to one another. As a result, it is possible to improve linearity in detection of a voltage, and accordingly, widen dynamic range in signal power control.
In addition, it may be possible to further widen dynamic range for signal power control, by locating a variable attenuator upstream of the detection diodes and turning the variable attenuator on or off in accordance with a control signal.
BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a circuit diagram of a conventional RF detection circuit.
Fig. 2 is a circuit diagram of a RF detection circuit in accordance with the first embodiment of the present invention.
[I:\DayLib\LIBQ]01112.doc:edg Fig. 3 is a block diagram of a mobile communicator including the RF detection circuit in accordance with the first embodiment.
Fig. 4 is a graph showing detection characteristics of the two detection diodes employed in the RF detection circuit in accordance with the first embodiment.
Fig. 5 is a graph showing combined detection characteristic of the two detection diodes employed in the RF detection circuit in accordance with the first embodiment.
Fig. 6 is a circuit diagram of a RF detection circuit in accordance S: 10 with the second embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] 9 Fig. 2 is a circuit diagram of a RF detection circuit in accordance 15 with the first embodiment.
As illustrated in Fig. 2, the RF detection circuit is comprised of a quadrature modulator 5 receiving IF signal and IQ signal, modulating those signals, and transmitting a single output signal, an interstage filter 16 receiving the output signal from the quadrature modulator 5, filtering the output signal, and transmitting the filtered signal, a power amplifier 4 receiving the filtered signal from the interstage filter 16, amplifying the signal and transmitting an output signal, a directional coupler 24 receiving the output signal from the power amplifier 4 and branching the received output signal into two first signals, a distributor 23 receiving one of the first signals from the directional coupler 24, and dividing the received first signal into two second signals, a first detection diode 21 receiving one of the second signals from the distributor 23, detecting the received second signal, and transmitting a first output signal, a first buffer amplifier 19 receiving the first output signal from the first detection diode 21, amplifying the received first output signal, and transmitting a signal, a second detection diode 22 receiving one of the second signals from the distributor 23, detecting the received second signal, and transmitting a second output signal, a second buffer amplifier 20 receiving the second output signal from the second detection diode 22, amplifying the received second output signal, and transmitting a signal, an adding amplifier 18 receiving the signals at a positive terminal from the first and second buffer amplifiers 19 and 20, and grounded at a negative terminal, and a comparison circuit 17 receiving both an output signal transmitted from the adding amplifier 18 and a control signal transmitted from a controller (not illustrated), comparing those signals to each other, and transmitting a signal 10 indicative of comparison, to the quadrature modulator 5, as a feed-back signal.
A first resistor 38 is electrically connected at one end to the directional coupler 24 and grounded at the other end.
*A first capacitor 36 is electrically connected in series between the directional coupler 24 and the first detection diode 21. A second capacitor 37 is 15 electrically connected in series between the directional coupler 24 and the second **"detection diode 22.
A first choke coil 34 is electrically connected at one end to a node between the first capacitor 36 and the first detection diode 21, and electrically connected at the other end to a voltage source VB. A second choke coil 35 is electrically connected at one end to a node between the second capacitor 37 and the second detection diode 22, and electrically connected at the other end to a voltage source VB.
A second resistor 31 is electrically connected to a node between the first detection diode 21 and the first buffer amplifier 19, and grounded at the other end. A third capacitor 30 is electrically connected at one end in parallel with the second resistor 31, and grounded at the other end.
A third resistor 33 is electrically connected to a node between the second detection diode 22 and the second buffer amplifier 20, and grounded at the other end. A fourth capacitor 32 is electrically connected at one end in parallel with the third resistor 33, and grounded at the other end.
A fourth resistor 28 is electrically connected in series between the first buffer amplifier 19 and the positive terminal of the adding amplifier 18. A fifth resistor 29 is electrically connected in series between the second buffer amplifier 20 and the positive terminal of the adding amplifier 18.
The adding amplifier 18 is grounded at the negative terminal through a sixth resistor 27.
A seventh resistor 26 is electrically connected between the negative terminal and an output port of the adding amplifier 18.
10 A portion encircled with a broken line defines an auto power control (APC) circuit 6.
Hereinbelow is explained an operation of the RF detection circuit in accordance with the first embodiment.
The RF signals are first modulated in the quadrature modulator filtered in the interstage filter 16, and then, amplified in the power amplifier 4.
First, the RF signal having been amplified by the power amplifier 4 is received in the coupler 24. The RF signal is divided into two portions by the hybrid distributor 23. Each of the two portions is introduced into each of the first and second detection diodes 21 and 22.
Output voltages are transmitted from the first and second detection diodes 21 and 22 to the adding amplifier 18 through the first and second buffers 19 and 20, and are added to each other in the adding amplifier 18.
Then, the adding amplifier 18 transmits an output signal to the comparison circuit 17.
The comparison circuit 17 received the output signal transmitted from the adding amplifier 18 and a control signal transmitted from a controller (not illustrated), compares these signals to each other, and transmits a signal indicative of the result of comparison, to the quadrature modulator 5, as a feedback signal FS.
Hereinbelow are explained detection characteristics of the first and second detection diodes 21 and 22.
Fig. 4 illustrates each of the detection characteristics of the first and second detection diodes 21 and 22.
As illustrated in Fig. 4, the first detection diode 21 has such a characteristic as indicated with the curve A. Specifically, the first detection diode 21 can detect a voltage in the range of about 0.3V to 2.0V when the signal power is in the range of about -30 dBm to about 5 dBm. The second detection diode 22 10 has such a characteristic as indicated with the curve B. Specifically, the second 10 detection diode 22 can detect a voltage in the range of about 0.3V to 2.0V when the signal power is in the range of about 5 dBm to about 30 dBm.
Fig. 5 illustrates detection characteristic obtained by combing the *."detection characteristics of the first and second detection diodes 21 and 22.
By combining the detection characteristics of the first and second 15 detection diodes 21 and 22, there is obtained a detection characteristic as indicated in Fig. 5 with the curve Specifically, a combination of the first and second detection diodes 21 and 22 electrically connected in parallel to each other can detect a voltage in the range of about 0.3V to 4.0V when the signal power is in the range of about -30 dBm to about 30 dBm.
Accordingly, the first embodiment makes it possible to provide detection characteristic in a wider range than that of the conventional RF detection circuit including a single detection diode.
Fig. 3 is a block diagram of an example of a RF circuit including the RF detection circuit in accordance with the first embodiment, illustrated in Fig. 2. The RF circuit is employed, for instance, in a mobile communicator such as a cellular phone.
The illustrated RF circuit is comprised of a first antenna 1, a second antenna 2, an antenna switch 3 electrically connected to the first antenna 1, and switching the first antenna 1 between a receiver and a transmitter, a controller 8 transmitting a control signal to a later mentioned auto power control circuit 6, a modem or a modulator and demodulator 7 controlled by the controller 8 and transmitting IF signals to a later mentioned quadrature modulator 5, a power amplifier 4 receiving an output signal from the quadrature modulator and amplifying the output signal, an auto power control (APC) circuit 6 as defined in Fig. 2 with a broken line, a synthesizer 9 transmitting I, Q signal to both the quadrature modulator 5 and later mentioned first and second mixers 12 and 13, a first RF amplifier 10 receiving a signal having been received through the first *...antenna 1, from the antenna switch 3, a second RF amplifier 11 receiving a signal 10 having been received through the second antenna 2, a first mixer 12 receiving I, Q l signal from the synthesizer 9 and an output signal from the first RF amplifier and transmitting an output signal to a later mentioned first IF amplifier 14, a second mixer 13 receiving I, Q signal from the synthesizer 9 and an output signal from the second RF amplifier 11, and transmitting an output signal to a later 15 mentioned second IF amplifier 15, a first IF amplifier 14 receiving an output signal from the first mixer 12, amplifying the output signal, and transmitting the amplified signal to the modem 7, and a second IF amplifier 15 receiving an output signal from the second mixer 13, amplifying the output signal, and transmitting the amplified signal to the modem 7.
In the RF circuit illustrated in Fig. 3, the first antenna 1 and the second antenna 2 cooperate with each other to accomplish antenna diversity.
In operation, the controller 8 transmits a control signal CS to the comparison circuit 17 in the auto power control circuit 6. Then, the RF detection circuit defined by the quadrature modulator 5, the power amplifier 4 and the auto power control circuit 6 operates in such a manner as having been explained with reference to Fig. 2. As a result, the comparison circuit 17 transmits the feedback signal FS to the quadrature modulator [Second Embodiment] Fig. 6 is a circuit diagram of a RF detection circuit in accordance with the second embodiment.
As illustrated in Fig. 6, the RF detection circuit is comprised of a quadrature modulator 5 receiving IF signal and IQ signal, modulating those signals, and transmitting a single output signal, an interstage filter 16 receiving the output signal from the quadrature modulator 5, filtering the output signal, and transmitting the filtered signal, a power amplifier 4 receiving the filtered signal from the interstage filter 16, amplifying the signal and transmitting an output signal, a directional coupler 24 receiving the output signal from the power S. amplifier 4 and branching the received output signal into two first signals, a 10 variable attenuator 25 receiving one of the first signals from the directional coupler 24, attenuating the received first signal, and transmitting the attenuated first signal, a distributor 23 receiving the first signal from the variable attenuator 25, and dividing the received first signal into two second signals, a first detection diode 21 receiving one of the second signals from the distributor 23, detecting the 15 received second signal, and transmitting a first output signal, a first buffer amplifier 19 receiving the first output signal from the first detection diode 21, amplifying the received first output signal, and transmitting a signal, a second detection diode 22 receiving one of the second signals from the distributor 23, detecting the received second signal, and transmitting a second output signal, a second buffer amplifier 20 receiving the second output signal from the second detection diode 22, amplifying the received second output signal, and transmitting a signal, an adding amplifier 18 receiving the signals at a positive terminal from the first and second buffer amplifiers 19 and 20, and grounded at a negative terminal, and a comparison circuit 17 receiving both an output signal transmitted from the adding amplifier 18 and a control signal transmitted from a controller (not illustrated), comparing those signals to each other, and transmitting a signal indicative of comparison, to the quadrature modulator 5, as a feed-back signal.
A first resistor 38 is electrically connected at one end to the directional coupler 24 and grounded at the other end.
.1 A first capacitor 36 is electrically connected in series between the directional coupler 24 and the first detection diode 21. A second capacitor 37 is electrically connected in series between the directional coupler 24 and the second detection diode 22.
A first choke coil 34 is electrically connected at one end to a node between the first capacitor 36 and the first detection diode 21, and electrically connected at the other end to a voltage source VB. A second choke coil 35 is electrically connected at one end to a node between the second capacitor 37 and the second detection diode 22, and electrically connected at the other end to a voltage source VB.
A second resistor 31 is electrically connected to a node between the first detection diode 21 and the first buffer amplifier 19, and grounded at the other end. A third capacitor 30 is electrically connected at one end in parallel with the second resistor 31, and grounded at the other end.
A third resistor 33 is electrically connected to a node between the second detection diode 22 and the second buffer amplifier 20, and grounded at the other end. A fourth capacitor 32 is electrically connected at one end in parallel with the third resistor 33, and grounded at the other end.
A fourth resistor 28 is electrically connected in series between the first buffer amplifier 19 and the positive terminal of the adding amplifier 18. A fifth resistor 29 is electrically connected in series between the second buffer amplifier 20 and the positive terminal of the adding amplifier 18.
The adding amplifier 18 is grounded at the negative terminal through a sixth resistor 27.
A seventh resistor 26 is electrically connected between the negative terminal and an output port of the adding amplifier 18.
A portion encircled with a broken line defines an auto power control (APC) circuit 6.
In comparison with the first embodiment illustrated in Fig. 2, the
S
S*
S
RF detection circuit in accordance with the second embodiment is additionally comprised of the variable attenuator The variable attenuator 25 is operated as follows.
For instance, if a RF signal has a level equal to or greater than a first predetermined level, the variable attenuator 25 is kept on. Since the RF signal has a great level, even if the RF signal level is attenuated by the variable attenuator 25, the first and second diodes 21 and 22 can sufficiently detect the RF signal.
If the RF signal has a level equal to or lower than a second 10 predetermined level, the variable attenuator 25 is turned off to thereby allow the RF signal to pass therethrough.
As mentioned earlier, in accordance with the second embodiment, since detection capability of the first and second diodes 21 and 22 can be effectively utilized by controlling a level of a RF signal, it is possible to detect RF signal power in a higher dynamic range.
It is not always necessary to frequently operate the variable attenuator 25 to widen a dynamic range, because the RF signal power tends to be discontinued while the variable attenuator 25 is in control. It is preferable that detection characteristic is first improved by operating the two detection diodes 21 and 22 in parallel like the first embodiment, and is further improved by the attenuator control, if necessary.
The RF circuit illustrated in Fig. 3 may be designed to include the RF detection circuit in accordance with the second embodiment, illustrated in Fig.
6, in place of the RF detection circuit in accordance with the first embodiment, illustrated in Fig. 2.
The RF detection circuits in accordance with the first and second embodiments are designed to include two detection diodes, that is, the first and second detection diodes 21 and 22. However, it should be noted that the number of detection diodes in the RF detection circuit is not to be limited to two. The RF detection circuit may be designed to include three or more detection diodes electrically connected in parallel with one another.
a *p a* *p 14
Claims (9)
1. A radio frequency detection circuit comprising: a modulator receiving first and second signals, and transmitting an output signal; a directional coupler receiving said output signal from said modulator, and dividing the thus received output signal into two first signals; a distributor receiving one of said two first signals from said directional coupler, and dividing the thus received first signal into N second signals wherein N is an 1o integer equal to or greater than 2; first the N-th diodes each receiving one of said N second signals from said distributor, and transmitting a first to N-th output signal; an adder adding said first to N-th output signals to one another, and transmitting a sum signal; and Is a comparison circuit receiving said sum signal and a control signal, comparing said sum signal to said control signal, and transmitting a feed-back signal indicative of comparison, to said modulator.
2. The radio frequency detection circuit as set forth in claim 1, further comprising 20 an attenuator electrically connected in series between said directional coupler and said S: distributor, said attenuator receiving said control signal in accordance with which said attenuator is turned on or off.
3. The radio frequency detection circuit as set forth in claim 2, wherein said attenuator is turned on when said control signal has a level equal to or greater than a first threshold level, and is turned off when said control signal has a level equal to or smaller than a second threshold level.
4. The radio frequency detection circuit as set forth in claim 2, wherein said attenuator is a variable attenuator. The radio frequency detection circuit as set forth in any one of claim 1 to 4, further comprising first to N-th buffer amplifiers each electrically connected in series between said first to N-th diodes and said adder. [I:\DayLib\LIBQ]01 I 12.doc:edg -16-
6. The radio frequency detection circuit as set forth in any one of claim 1 to 4, further comprising first to N-th capacitors each electrically connected in series between said distributor and said first to N-th diodes.
7. A method of detecting radio frequency, comprising the steps of: modulating first and second signals, and transmitting an output signal; dividing said output signal into N first signals wherein N is an integer equal to or greater than 2; detecting said N first signals, and resultingly transmitting N second signals; adding said N second signals to one another, and transmitting a sum signal; and comparing said sum signal to a control signal, and transmitting a feed- back signal indicative of comparison, said feed-back signal being fed back to said step
8. The method as set forth in claim 7, further comprising the step of attenuating S-said output signal, said step being to be carried out after said step but prior to said step
9. A radio frequency circuit to be used in a mobile transceiver, comprising: a controller transmitting a control signal; a modem transmitting first and second signals; a modulator receiving said first and second signals, and transmitting an output signal; a directional coupler receiving said output signal from said modulator, and dividing the thus received output signal into two first signals; a distributor receiving one of said two first signals from said directional coupler, and dividing the thus received first signal into N second signals wherein N is an integer equal to or greater than 3; first to N-th diodes each receiving one of said N second signals from said distributor, and transmitting a first to N-th output signal; an adder adding said first to N-th output signals to one another, and RR t transmitting a sum signal; and fI:\DayLib\LIBQ]01 I 12.doc:edg
17- a comparison circuit receiving said sum signal and said control signal, comparing said sum signal to said control signal, and transmitting a feed-back signal indicative of comparison, to said modulator. 10. The radio frequency detection circuit as set forth in claim 9, further comprising an attenuator electrically connected in series between said directional coupler and said distributor, said attenuator receiving said control signal in accordance with which said attenuator is turned on or off. 11. The radio frequency detection circuit as set forth in claim 10, wherein said attenuator is turned on when said control signal has a level equal to or greater than a first .threshold level, and is turned off when said control signal has a level equal to or smaller than a second threshold level. 12. The radio frequency detection circuit as set forth in claim 10 or 11, wherein said S: attenuator is a variable attenuator. i: 13. A radio frequency detection circuit substantially as described herein with reference to Figures 2 to 6 of the accompanying drawings. 14. A method of detecting radio frequency substantially as described herein with reference to Figures 2 to 6 of the accompanying drawings. A radio frequency circuit substantially as described herein with reference to Figures 2 to 6 of the accompanying drawings. DATED this twentieth Day of March, 2002 NEC Corporation Patent Attorneys for the Applicant SPRUSON FERGUSON [1:\DayLib\LIBQ]011 12.doc:edg
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11-161592 | 1999-06-08 | ||
| JP11161592A JP2000349657A (en) | 1999-06-08 | 1999-06-08 | Rf detection circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU3795300A AU3795300A (en) | 2000-12-14 |
| AU747958B2 true AU747958B2 (en) | 2002-05-30 |
Family
ID=15738078
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU37953/00A Ceased AU747958B2 (en) | 1999-06-08 | 2000-06-06 | Radio frequency (RF) detection circuit |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP2000349657A (en) |
| AU (1) | AU747958B2 (en) |
| GB (1) | GB2350955B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107462766A (en) * | 2017-08-25 | 2017-12-12 | 上海蓝瑞电气有限公司 | Detect the new method and detection circuit of line voltage and mains frequency |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001016116A (en) | 1999-07-02 | 2001-01-19 | Nec Corp | Portable radio equipment |
| DE60136070D1 (en) * | 2000-07-28 | 2008-11-20 | Harris Corp | SUCCESSIVE LOG VIDEO CONNECTION, POWER DETECTOR AND METHOD |
| US7317902B2 (en) | 2001-06-28 | 2008-01-08 | Harris Corporation | Successive log video pad power detector and method |
| JP4365541B2 (en) * | 2001-04-18 | 2009-11-18 | アルプス電気株式会社 | Transmitter detection circuit |
| CN1459149A (en) * | 2001-07-17 | 2003-11-26 | 三菱电机株式会社 | Transmission power control circuit |
| CN106353586B (en) * | 2016-10-21 | 2023-07-04 | 成都前锋电子仪器有限责任公司 | Coupling detection circuit |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5126686A (en) * | 1989-08-15 | 1992-06-30 | Astec International, Ltd. | RF amplifier system having multiple selectable power output levels |
| WO1992020152A1 (en) * | 1991-05-02 | 1992-11-12 | Wavetek Microwave, Inc. | Rf power sensor having improved linearity over greater dynamic range_____________________________________________________________ |
| EP1043592A1 (en) * | 1999-04-09 | 2000-10-11 | Agilent Technologies Inc | True average wide dynamic range microwave power sensor using diode stack attenuator |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4791380A (en) * | 1987-10-09 | 1988-12-13 | Microphase Corporation | Detector circuit with dual-diode compensation |
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1999
- 1999-06-08 JP JP11161592A patent/JP2000349657A/en active Pending
-
2000
- 2000-06-06 AU AU37953/00A patent/AU747958B2/en not_active Ceased
- 2000-06-07 GB GB0013867A patent/GB2350955B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5126686A (en) * | 1989-08-15 | 1992-06-30 | Astec International, Ltd. | RF amplifier system having multiple selectable power output levels |
| WO1992020152A1 (en) * | 1991-05-02 | 1992-11-12 | Wavetek Microwave, Inc. | Rf power sensor having improved linearity over greater dynamic range_____________________________________________________________ |
| EP1043592A1 (en) * | 1999-04-09 | 2000-10-11 | Agilent Technologies Inc | True average wide dynamic range microwave power sensor using diode stack attenuator |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107462766A (en) * | 2017-08-25 | 2017-12-12 | 上海蓝瑞电气有限公司 | Detect the new method and detection circuit of line voltage and mains frequency |
| CN107462766B (en) * | 2017-08-25 | 2020-03-27 | 上海蓝瑞电气有限公司 | New method for detecting mains voltage and mains frequency and detection circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| AU3795300A (en) | 2000-12-14 |
| GB0013867D0 (en) | 2000-08-02 |
| GB2350955B (en) | 2001-08-29 |
| JP2000349657A (en) | 2000-12-15 |
| GB2350955A (en) | 2000-12-13 |
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| Date | Code | Title | Description |
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| FGA | Letters patent sealed or granted (standard patent) |