CA2164465A1 - Converter for converting a modulating signal with variable envelope to two modulating signals without variable envelope, transmitter using the converter and method for transmitting a modulated wave with variable envelope - Google Patents
Converter for converting a modulating signal with variable envelope to two modulating signals without variable envelope, transmitter using the converter and method for transmitting a modulated wave with variable envelopeInfo
- Publication number
- CA2164465A1 CA2164465A1 CA002164465A CA2164465A CA2164465A1 CA 2164465 A1 CA2164465 A1 CA 2164465A1 CA 002164465 A CA002164465 A CA 002164465A CA 2164465 A CA2164465 A CA 2164465A CA 2164465 A1 CA2164465 A1 CA 2164465A1
- Authority
- CA
- Canada
- Prior art keywords
- signal
- sqrt
- modulating
- modulated wave
- quadrature
- 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.)
- Abandoned
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
- H03F1/02—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
- H03F1/0205—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in transistor amplifiers
- H03F1/0294—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in transistor amplifiers using vector summing of two or more constant amplitude phase-modulated signals
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
- H04L27/20—Modulator circuits; Transmitter circuits
- H04L27/2032—Modulator circuits; Transmitter circuits for discrete phase modulation, e.g. in which the phase of the carrier is modulated in a nominally instantaneous manner
- H04L27/2053—Modulator circuits; Transmitter circuits for discrete phase modulation, e.g. in which the phase of the carrier is modulated in a nominally instantaneous manner using more than one carrier, e.g. carriers with different phases
- H04L27/206—Modulator circuits; Transmitter circuits for discrete phase modulation, e.g. in which the phase of the carrier is modulated in a nominally instantaneous manner using more than one carrier, e.g. carriers with different phases using a pair of orthogonal carriers, e.g. quadrature carriers
- H04L27/2067—Modulator circuits; Transmitter circuits for discrete phase modulation, e.g. in which the phase of the carrier is modulated in a nominally instantaneous manner using more than one carrier, e.g. carriers with different phases using a pair of orthogonal carriers, e.g. quadrature carriers with more than two phase states
- H04L27/2071—Modulator circuits; Transmitter circuits for discrete phase modulation, e.g. in which the phase of the carrier is modulated in a nominally instantaneous manner using more than one carrier, e.g. carriers with different phases using a pair of orthogonal carriers, e.g. quadrature carriers with more than two phase states in which the data are represented by the carrier phase, e.g. systems with differential coding
Abstract
A base band waveform generation circuit 10 calculates the equations: I1 = {I+Q SQRT(4/a2 - 1)}/2; Q1 = {Q-I
SQRT(4/a2 - 1)}/2; I2 = {I-Q SQRT(4/a2 - 1)}/2; and Q2 =
{Q+I SQRT(4/a2 - 1)}/2, based on I and Q of a modulating signal. Where, SQRT(x) refers to a square root of x, that is, a2 = (I2)2 + (Q2)2. A quadrature modulator 12 quadrature modulates a carrier with the I1 and Q1. A
quadrature modulator 22 quadrature modulates a carrier with the I2 and Q2. The output signals of the quadrature modulators 12 and 13 are amplified with a transmission power amplifiers 13 and 23, then composed.
SQRT(4/a2 - 1)}/2; I2 = {I-Q SQRT(4/a2 - 1)}/2; and Q2 =
{Q+I SQRT(4/a2 - 1)}/2, based on I and Q of a modulating signal. Where, SQRT(x) refers to a square root of x, that is, a2 = (I2)2 + (Q2)2. A quadrature modulator 12 quadrature modulates a carrier with the I1 and Q1. A
quadrature modulator 22 quadrature modulates a carrier with the I2 and Q2. The output signals of the quadrature modulators 12 and 13 are amplified with a transmission power amplifiers 13 and 23, then composed.
Description
~ 2164465 C~.V~ FOR CO`NV~1NG A MODULATING SIGNAL WITH U~pT~RT.~.
ENVELOPE TO TWO MODULATING SIGNALS WITHOUT VpRT~RT-~
ENVELOPE, T~S~I'1L~K USING THE CO1.V~KTER
AND
METHOD FOR TRANSMITTING A MODULATED WAVE WITH VApT~RT-~
ENVELOPE
R~K~OUND OF THE lNv~LlON
o The present invention relates to an art for transmitting a modulated wave with variable envelope, such as 4-phase Phase Shift Keying (hereinafter referred to as PSK), ~/4 shift Differential Quadrature Phase Shift Keying (hereinafter referred to as DQPSK) and the like.
A conventional digital cellular phone system employs a linear modulation method using a modulated wave with a narrow band width such as ~/4 shift DQPSK for efficient use of frequency. However this linear modulation method varies the amplitude of transmission radio wave to a great degree compared to the conventional constant envelope modulation method (where the envelope does not vary) employing Frequency Modulation (hereinafter referred to as FM), Gaussian Minimum Shift Keying (hereinafter referred to as GMSK) modulation and the like. As a result, a transmitter is required to transmit the above-described ~_ 21 64465 amplitude variation accurately. That is why a linear amplifier has to be used in spite of its ineffectiveness.
Fig. 3 shows a block diagram of a conventional transmitter.
A base band waveform generation circuit 1 receives an incoming input data signal 7, synchronizing with a clock 8 and outputs corresponding base band signals (modulating signal) I and Q, respectively. The signal I
lo refers to an in-phase component of the transmisslonradio wave to the carrier. The signal Q refers to a quadrature component.
These signals are input to an quadrature modulator 2 for quadrature modulating a local signal (carrier) output from a local oscillator 6. Output signals (modulated signal) of the quadrature modulator 2 are amplified with a transmission power amplifier 3 and transmitted from an antenna 5 after eliminated unnecessary waves through a transmission filter 4.
The output of the quadrature modulator 2 as linear modulation such as ~/4 shift DQPSK, QPSK and the like, is accompanied with the envelope amplitude variation because of using no constant envelope modulation. The transmission power amplifier 3 has to be a linear 2s amplifier in order to reproduce the envelope amplitude variation as accurate as possible.
Fig. 4 is a graphlcal representation of - characteristics of a transmission power amplifier. An axis of abscissa is an input level, a left axis of ordinates is an output level and a right axis of ordinates is efficiency. The solid line designates a relationship between input power and output power. The dotted line designates a relationship between the input power and efficiency.
The conventional transmission method has no chance but uses the area where the output power linearly varles to the input power in order to conduct linear amplification. This area, however, exhibits quite low efficiency. Moreover the conventional method increases power consumption for transmission compared with the constant envelope modulation method applicable in the non-linear area (lower right section of the graph of Fig. 4).
The above described conventional method for amplifying the linear modulated wave with the linear amplifier exhibits quite low power efficiency, resulting in excessive power consumption increase.
SUMM~RY OF THE l~v~NL-lON
It is an object of the invention to provide a solution for the aforementioned problem.
~_ 21 64465 Another object of the invention is to provide a transmitter and a method enabling to use a non-linear and efficient amplifier for transmission power amplification.
The aforementioned present invention is achieved by a converter for converting a modulating signal with envelope variation to two modulating signals without envelope variation, the converter comprising means for converting a signal of the modulating signal with o envelope variation of which in-phase component signal is I and quadrature component signal is Q to a signal of which in-phase component signal is I1, and quadrature component signal is Q1 and a signal of which in-phase component signal is I2, and quadrature component signal is Q2 that meet the following conditions (1) to (3):
(I1)2 + (Q1)2 = constant (1) (I2)2 + (Q2)2 = constànt (2) Vector (I,Q) = Vector (I1,Q1) + Vector (I2,Q2) (3).
Moreover, the aforementioned present invention is achieved by a transmitter comprising:
means for converting a signal of the modulating signal with envelope variation of which in-phase component signal is I and quadrature component signal is Q to a signal (of which in-phase component signal is I1, and quadrature component . ~ 2164465 signal ls Ql) and a signal (of which in-phase component signal is I2, and quadrature component signal is Q2) that meet the following conditions (1) to (3):
S (Il)2 + (Ql)2 = constant (1) (I2)2 + (Q2)2 = constant (2) Vector (I,Q) = Vector (Il,Ql) + Vector (I2,Q2) (3), a first modulation means for modulating a carrier with the signal (Il,Ql) and generating a first modulated o wave;
a second modulation means for modulating a carrier with the signal (I2,Q2) and generating a second modulated wave;
a first amplification means for power amplifying the lS first modulated wave;
a second amplification means for power amplifying the second modulated wave; and means for composing outputs signals of the first amplification means and the second amplification means.
Furthermore, the aforementioned present invention is achieved by a method for transmitting a modulated wave with envelope variation, the method comprising steps of:
converting a signal of the modulating signal with envelope variation of which in-phase component signal ls I and quadrature component signal is Q
to a signal of which in-phase component signal is Il, and quadrature component signal is Ql and a signal of which in-phase component signal is I2, and quadrature çomponent signal is Q2 that meet the following conditions (1) to (3):
(Il)2 + (Ql)2 = constant (1) (I2)2 + (Q2)2 = constant (2) Vector (I,Q) = Vector (Il,Ql) + Vector (I2,Q2) (3);
a first modulation step of modulating a carrier with the signal (Il,Ql) and generating a first modulated wavei a second modulation step of modulating a carrier with the signal (I2,Q2) and generating a second S modulated wave;
a first amplification step of power amplifying the first modulated wave;
a second amplification step of power amplifying the second modulated wave;
composing the first power amplified modulated wave and the second power amplified modulated wave;
band limiting a composed modulated wave; and transmitting a band limited modulated wave.
The present invention converts a modulating signal of which amplitude is variable (i.e., of which envelope is - ~ 21 64465 variable) to two constant envelope modulating signals.
Then the present invention modulates, amplifies and composes respective carriers by using respective constant envelope modulating signals. Thus, the present invention allows to use a non-linear and highly efficient amplifier, resulting decreasing of power consumptlon.
BRIEF DESCRIPTION OF T B DRAWINGS
This and other objects, features and advantages of the present invention will become more apparent upon a reading of the following detailed description and drawings, in which:
Fig. 1 is a figure for explaining a principle of the present invention;
Fig. 2 is a block diagram of an embodiment of the present invention;
Fig. 3 is a block diagram of a conventional transmitter; and Fig. 4 is a figure showing characteristics of a transmission power amplifier.
DESCRIPTION OF TB PREFERRED EMBODIMENTS
A principle of the present invention is hereinafter described.
Fig. 1 is a vector representation of phase and 2s amplitude of a signal.
~_: 21 64465 Assuming that a vector of a transmission modulating signal is designated as A, in-phase component to the carrier is designated as I and quadrature component is designated as Q, the vector A is expressed as the following coordinate:
A = (I, Q) ... (1) Assuming that an amplitude "a" of the vector A is variable, each vector of Al and A2 is supposed to have a constant amplitude with its value equal to or more than o 1/2 of the maximum value of the amplitude "a". It is assumed that A1 and A2 have the same amplitude values of 1 for simplification ~i.e., a < 2). The vectors Al and A2 are expressed as the following coordinates:
Al = (Il, Ql), A2 = (I2, Q2) The values of Il, Q1l I2 and Q2 are selected so that the sum of the vectors Al and A2 is equal to the vector A.
Each of the above value is obtained by the following equations of (3-1) to (3-4).
Il = {I+Q SQRT(4/a2 - 1)}/2 .... (3-1) Q1 = {Q-I SQRT(4/a2 - 1)}/2 .... (3-2) I2 = {I-Q SQRT(4/a2 - 1)}/2 .... (3-3) Q2 = {Q+I SQRT(4/a2 - 1)}/2 .... (3-4) where SQRT(x) refers to a square root of the x. The above equations (3-1) to (3-4) obviously show that:
2s I12 + Q12 = 1 and I22 + Q22 = 1. This represents that
ENVELOPE TO TWO MODULATING SIGNALS WITHOUT VpRT~RT-~
ENVELOPE, T~S~I'1L~K USING THE CO1.V~KTER
AND
METHOD FOR TRANSMITTING A MODULATED WAVE WITH VApT~RT-~
ENVELOPE
R~K~OUND OF THE lNv~LlON
o The present invention relates to an art for transmitting a modulated wave with variable envelope, such as 4-phase Phase Shift Keying (hereinafter referred to as PSK), ~/4 shift Differential Quadrature Phase Shift Keying (hereinafter referred to as DQPSK) and the like.
A conventional digital cellular phone system employs a linear modulation method using a modulated wave with a narrow band width such as ~/4 shift DQPSK for efficient use of frequency. However this linear modulation method varies the amplitude of transmission radio wave to a great degree compared to the conventional constant envelope modulation method (where the envelope does not vary) employing Frequency Modulation (hereinafter referred to as FM), Gaussian Minimum Shift Keying (hereinafter referred to as GMSK) modulation and the like. As a result, a transmitter is required to transmit the above-described ~_ 21 64465 amplitude variation accurately. That is why a linear amplifier has to be used in spite of its ineffectiveness.
Fig. 3 shows a block diagram of a conventional transmitter.
A base band waveform generation circuit 1 receives an incoming input data signal 7, synchronizing with a clock 8 and outputs corresponding base band signals (modulating signal) I and Q, respectively. The signal I
lo refers to an in-phase component of the transmisslonradio wave to the carrier. The signal Q refers to a quadrature component.
These signals are input to an quadrature modulator 2 for quadrature modulating a local signal (carrier) output from a local oscillator 6. Output signals (modulated signal) of the quadrature modulator 2 are amplified with a transmission power amplifier 3 and transmitted from an antenna 5 after eliminated unnecessary waves through a transmission filter 4.
The output of the quadrature modulator 2 as linear modulation such as ~/4 shift DQPSK, QPSK and the like, is accompanied with the envelope amplitude variation because of using no constant envelope modulation. The transmission power amplifier 3 has to be a linear 2s amplifier in order to reproduce the envelope amplitude variation as accurate as possible.
Fig. 4 is a graphlcal representation of - characteristics of a transmission power amplifier. An axis of abscissa is an input level, a left axis of ordinates is an output level and a right axis of ordinates is efficiency. The solid line designates a relationship between input power and output power. The dotted line designates a relationship between the input power and efficiency.
The conventional transmission method has no chance but uses the area where the output power linearly varles to the input power in order to conduct linear amplification. This area, however, exhibits quite low efficiency. Moreover the conventional method increases power consumption for transmission compared with the constant envelope modulation method applicable in the non-linear area (lower right section of the graph of Fig. 4).
The above described conventional method for amplifying the linear modulated wave with the linear amplifier exhibits quite low power efficiency, resulting in excessive power consumption increase.
SUMM~RY OF THE l~v~NL-lON
It is an object of the invention to provide a solution for the aforementioned problem.
~_ 21 64465 Another object of the invention is to provide a transmitter and a method enabling to use a non-linear and efficient amplifier for transmission power amplification.
The aforementioned present invention is achieved by a converter for converting a modulating signal with envelope variation to two modulating signals without envelope variation, the converter comprising means for converting a signal of the modulating signal with o envelope variation of which in-phase component signal is I and quadrature component signal is Q to a signal of which in-phase component signal is I1, and quadrature component signal is Q1 and a signal of which in-phase component signal is I2, and quadrature component signal is Q2 that meet the following conditions (1) to (3):
(I1)2 + (Q1)2 = constant (1) (I2)2 + (Q2)2 = constànt (2) Vector (I,Q) = Vector (I1,Q1) + Vector (I2,Q2) (3).
Moreover, the aforementioned present invention is achieved by a transmitter comprising:
means for converting a signal of the modulating signal with envelope variation of which in-phase component signal is I and quadrature component signal is Q to a signal (of which in-phase component signal is I1, and quadrature component . ~ 2164465 signal ls Ql) and a signal (of which in-phase component signal is I2, and quadrature component signal is Q2) that meet the following conditions (1) to (3):
S (Il)2 + (Ql)2 = constant (1) (I2)2 + (Q2)2 = constant (2) Vector (I,Q) = Vector (Il,Ql) + Vector (I2,Q2) (3), a first modulation means for modulating a carrier with the signal (Il,Ql) and generating a first modulated o wave;
a second modulation means for modulating a carrier with the signal (I2,Q2) and generating a second modulated wave;
a first amplification means for power amplifying the lS first modulated wave;
a second amplification means for power amplifying the second modulated wave; and means for composing outputs signals of the first amplification means and the second amplification means.
Furthermore, the aforementioned present invention is achieved by a method for transmitting a modulated wave with envelope variation, the method comprising steps of:
converting a signal of the modulating signal with envelope variation of which in-phase component signal ls I and quadrature component signal is Q
to a signal of which in-phase component signal is Il, and quadrature component signal is Ql and a signal of which in-phase component signal is I2, and quadrature çomponent signal is Q2 that meet the following conditions (1) to (3):
(Il)2 + (Ql)2 = constant (1) (I2)2 + (Q2)2 = constant (2) Vector (I,Q) = Vector (Il,Ql) + Vector (I2,Q2) (3);
a first modulation step of modulating a carrier with the signal (Il,Ql) and generating a first modulated wavei a second modulation step of modulating a carrier with the signal (I2,Q2) and generating a second S modulated wave;
a first amplification step of power amplifying the first modulated wave;
a second amplification step of power amplifying the second modulated wave;
composing the first power amplified modulated wave and the second power amplified modulated wave;
band limiting a composed modulated wave; and transmitting a band limited modulated wave.
The present invention converts a modulating signal of which amplitude is variable (i.e., of which envelope is - ~ 21 64465 variable) to two constant envelope modulating signals.
Then the present invention modulates, amplifies and composes respective carriers by using respective constant envelope modulating signals. Thus, the present invention allows to use a non-linear and highly efficient amplifier, resulting decreasing of power consumptlon.
BRIEF DESCRIPTION OF T B DRAWINGS
This and other objects, features and advantages of the present invention will become more apparent upon a reading of the following detailed description and drawings, in which:
Fig. 1 is a figure for explaining a principle of the present invention;
Fig. 2 is a block diagram of an embodiment of the present invention;
Fig. 3 is a block diagram of a conventional transmitter; and Fig. 4 is a figure showing characteristics of a transmission power amplifier.
DESCRIPTION OF TB PREFERRED EMBODIMENTS
A principle of the present invention is hereinafter described.
Fig. 1 is a vector representation of phase and 2s amplitude of a signal.
~_: 21 64465 Assuming that a vector of a transmission modulating signal is designated as A, in-phase component to the carrier is designated as I and quadrature component is designated as Q, the vector A is expressed as the following coordinate:
A = (I, Q) ... (1) Assuming that an amplitude "a" of the vector A is variable, each vector of Al and A2 is supposed to have a constant amplitude with its value equal to or more than o 1/2 of the maximum value of the amplitude "a". It is assumed that A1 and A2 have the same amplitude values of 1 for simplification ~i.e., a < 2). The vectors Al and A2 are expressed as the following coordinates:
Al = (Il, Ql), A2 = (I2, Q2) The values of Il, Q1l I2 and Q2 are selected so that the sum of the vectors Al and A2 is equal to the vector A.
Each of the above value is obtained by the following equations of (3-1) to (3-4).
Il = {I+Q SQRT(4/a2 - 1)}/2 .... (3-1) Q1 = {Q-I SQRT(4/a2 - 1)}/2 .... (3-2) I2 = {I-Q SQRT(4/a2 - 1)}/2 .... (3-3) Q2 = {Q+I SQRT(4/a2 - 1)}/2 .... (3-4) where SQRT(x) refers to a square root of the x. The above equations (3-1) to (3-4) obviously show that:
2s I12 + Q12 = 1 and I22 + Q22 = 1. This represents that
2 1 64465 ~, .
signals (Il,Ql) and (I2,Q2) are constant envelope modulating signals, respectively.
This also shows that:(Il,Ql) + (I2~Q2) = (I~ Q) As aforementioned, it is possible to obtain an envelope modulating signal with variable phase component (I, Q) by generating the constant envelope modulating signal with the phase component of (Il,Ql) and the the same valued constant envelope modulated wave with the phase component of (I2,Q2) and amplifying and composing 0 them with the same gain.
A transmitter of the present lnvention is described referring to Fig. 2.
As shown in Fig. 2, the transmitter of the present invention comprises a base band waveform generation circuit (converter) 10 for outputting base band signals (modulating signals) Il, Ql, I2 and Q2 based on an in-phase component signal I, quadrature component signal (modulating signal) Q and a clock 8 synchronized with input data; a first quadrature modulator 12 for quadrature modulating a local signal (carrier) output from a local oscillator 6 by using the in-phase component signal Il and the quadrature component signal Ql; a second quadrature modulator 22 for quadrature modulating a local signal (carrier) by using the in-2s phase component signal I2 and the quadrature component ~ 21 64465 signal Q2i a first transmission power amplifier 13 for amplifying the output signal of the first quadrature modulator 12, a second transmission power amplifier 23 for amplifying the output signal output from the second S quadrature modulator 22, a power composition device 9 for composing output signals of the transmission power amplifiers 13 and 14; a band pass filter 4 for band limiting the output signal of the power composition device 9 and an antenna 5 for transmitting the output signal of the band pass filter 4.
The base band waveform generation circuit 10 (the converter) applies equations (3-1) to (3-4) to the input data 7, supplies the in-phase component signal I1 and the quadrature component signal Q1 to the first quadrature modulator 12 and supplies the in-phase component signal I2 and the quadrature component signal Q2 to the second quadrature modulator 22.
Where, the base band waveform generation circuit 10 comprises a digital signal processor in which a software for calculating equations (3-1) to (3-4) is embedded.
The first quadrature modulator 12 quadrature modulates the local signaI (carrier) output from the local oscillator 6 with the in-phase component signal I1 and the quadrature component signal Q1.
2s The second quadrature modulator 22 quadrature modulates the local signal (carrier) with the in-phase component signal I2 and ~he quadrature component signal Output signals of the first quadrature modulator 12 S and the second quadrature modulator 22 are poweramplified through the first transmission power amplifier 13 and the second transmission power amplifier 23, respectively. Since the output signals of the first and the second quadrature modulators 12 and 22 are constant lo envelope modulated waves processed through the base band waveform generation circuit 10 as aforementioned, no distortion occurs in spite of power amplification with the non-linear and highly efficient power amplifier.
The output signals of the first and the second-transmission power amplifiers 13 and 23 are powercomposed through the power composition device 9. As a result, with the output signal of the power composition device 9, the local signal (carrier) is quadrature modulated with the in-phase component signal I and the quadrature component signal, thus providing the signal comparable to that of power amplified with no distortion.
The output signal of the power composition device 9 is supplied to the antenna 5 for transmission, after band limited with the band pass filter 4.
signals (Il,Ql) and (I2,Q2) are constant envelope modulating signals, respectively.
This also shows that:(Il,Ql) + (I2~Q2) = (I~ Q) As aforementioned, it is possible to obtain an envelope modulating signal with variable phase component (I, Q) by generating the constant envelope modulating signal with the phase component of (Il,Ql) and the the same valued constant envelope modulated wave with the phase component of (I2,Q2) and amplifying and composing 0 them with the same gain.
A transmitter of the present lnvention is described referring to Fig. 2.
As shown in Fig. 2, the transmitter of the present invention comprises a base band waveform generation circuit (converter) 10 for outputting base band signals (modulating signals) Il, Ql, I2 and Q2 based on an in-phase component signal I, quadrature component signal (modulating signal) Q and a clock 8 synchronized with input data; a first quadrature modulator 12 for quadrature modulating a local signal (carrier) output from a local oscillator 6 by using the in-phase component signal Il and the quadrature component signal Ql; a second quadrature modulator 22 for quadrature modulating a local signal (carrier) by using the in-2s phase component signal I2 and the quadrature component ~ 21 64465 signal Q2i a first transmission power amplifier 13 for amplifying the output signal of the first quadrature modulator 12, a second transmission power amplifier 23 for amplifying the output signal output from the second S quadrature modulator 22, a power composition device 9 for composing output signals of the transmission power amplifiers 13 and 14; a band pass filter 4 for band limiting the output signal of the power composition device 9 and an antenna 5 for transmitting the output signal of the band pass filter 4.
The base band waveform generation circuit 10 (the converter) applies equations (3-1) to (3-4) to the input data 7, supplies the in-phase component signal I1 and the quadrature component signal Q1 to the first quadrature modulator 12 and supplies the in-phase component signal I2 and the quadrature component signal Q2 to the second quadrature modulator 22.
Where, the base band waveform generation circuit 10 comprises a digital signal processor in which a software for calculating equations (3-1) to (3-4) is embedded.
The first quadrature modulator 12 quadrature modulates the local signaI (carrier) output from the local oscillator 6 with the in-phase component signal I1 and the quadrature component signal Q1.
2s The second quadrature modulator 22 quadrature modulates the local signal (carrier) with the in-phase component signal I2 and ~he quadrature component signal Output signals of the first quadrature modulator 12 S and the second quadrature modulator 22 are poweramplified through the first transmission power amplifier 13 and the second transmission power amplifier 23, respectively. Since the output signals of the first and the second quadrature modulators 12 and 22 are constant lo envelope modulated waves processed through the base band waveform generation circuit 10 as aforementioned, no distortion occurs in spite of power amplification with the non-linear and highly efficient power amplifier.
The output signals of the first and the second-transmission power amplifiers 13 and 23 are powercomposed through the power composition device 9. As a result, with the output signal of the power composition device 9, the local signal (carrier) is quadrature modulated with the in-phase component signal I and the quadrature component signal, thus providing the signal comparable to that of power amplified with no distortion.
The output signal of the power composition device 9 is supplied to the antenna 5 for transmission, after band limited with the band pass filter 4.
Claims (11)
1 A converter for converting a modulating signal with envelope variation to two modulating signals without envelope variation, said converter comprising means for converting a signal of said modulating signal with envelope variation of which in-phase component signal is I and quadrature component signal is Q to a signal of which in-phase component signal is I1, and quadrature component signal is Q1 and a signal of which in-phase component signal is I2, and quadrature component signal is Q2 that meet the following conditions (1) to (3):
(I1) + (Q1) = constant (1) (I2) + (Q2) = constant (2) Vector (I,Q) = Vector (I1, Q1) + Vector (I2, Q2) (3).
(I1) + (Q1) = constant (1) (I2) + (Q2) = constant (2) Vector (I,Q) = Vector (I1, Q1) + Vector (I2, Q2) (3).
2 The converter of claim 1, wherein said conversion means converts a signal of said modulating signal (I, Q) to a signal (I1,Q1) and a signal (I2,Q2) by applying the following equations (1) to (3):
I1 = {I+Q SQRT(4/a - 1)}/2 (4) Q1 = {Q-I SQRT(4/a - 1)}/2 (5) I2 = {I-Q SQRT(4/a - 1)}/2 (6) Q2 = {Q+I SQRT(4/a - 1)}/2 (7), where, SQRT(x) refers to a square root of x, that is, a =(I2) + (Q2).
I1 = {I+Q SQRT(4/a - 1)}/2 (4) Q1 = {Q-I SQRT(4/a - 1)}/2 (5) I2 = {I-Q SQRT(4/a - 1)}/2 (6) Q2 = {Q+I SQRT(4/a - 1)}/2 (7), where, SQRT(x) refers to a square root of x, that is, a =(I2) + (Q2).
3 A transmitter comprising:
means for converting a signal of said modulating signal with envelope variation of which in-phase component signal is I and quadrature component signal is Q to a signal (of which in-phase component signal is I1, and quadrature component signal is Q1) and a signal (of which in-phase component signal is I2, and quadrature component signal is Q2) that meet the following conditions (1) to (3):
(I1) + (Q1) = constant (1) (I2) + (Q2) = constant (2) Vector (I, Q) = Vector (I1, Q1) + Vector (I2, Q2) (3), a first modulation means for modulating a carrier with said signal (I1, Q1) and generating a first modulated wave;
a second modulation means for modulating a carrier with said signal (I2, Q2) and generating a second modulated wave;
a first amplification means for power amplifying said first modulated wave;
a second amplification means for power amplifying said second modulated wave; and means for composing outputs signals of said first amplification means and said second amplification means.
means for converting a signal of said modulating signal with envelope variation of which in-phase component signal is I and quadrature component signal is Q to a signal (of which in-phase component signal is I1, and quadrature component signal is Q1) and a signal (of which in-phase component signal is I2, and quadrature component signal is Q2) that meet the following conditions (1) to (3):
(I1) + (Q1) = constant (1) (I2) + (Q2) = constant (2) Vector (I, Q) = Vector (I1, Q1) + Vector (I2, Q2) (3), a first modulation means for modulating a carrier with said signal (I1, Q1) and generating a first modulated wave;
a second modulation means for modulating a carrier with said signal (I2, Q2) and generating a second modulated wave;
a first amplification means for power amplifying said first modulated wave;
a second amplification means for power amplifying said second modulated wave; and means for composing outputs signals of said first amplification means and said second amplification means.
4 The transmitter of claim 3, wherein said conversion means converts a signal of said modulating signal (I, Q) to a signal (I1, Q1) and a signal (I2, Q2) by applying the following equations (4) to (7):
I1 = (I+Q SQRT(4/a - 1)}/2 (4) Q1 = {Q-I SQRT(4/a - 1)}/2 (5) I2 = {I-Q SQRT(4/a - 1)}/2 (6) Q2 = {Q+I SQRT(4/a - 1)}/2 (7), where, SQRT(x) refers to a square root of x, that is, a = (I2) + (Q2).
I1 = (I+Q SQRT(4/a - 1)}/2 (4) Q1 = {Q-I SQRT(4/a - 1)}/2 (5) I2 = {I-Q SQRT(4/a - 1)}/2 (6) Q2 = {Q+I SQRT(4/a - 1)}/2 (7), where, SQRT(x) refers to a square root of x, that is, a = (I2) + (Q2).
The transmitter of claim 3, wherein said first modulation means and said second modulation means are quadrature modulators.
6 The transmitter of claim 3, wherein said first amplification means and said second amplification means are non-linear power amplifiers.
7 A transmitter comprising:
means for converting a signal of said modulating signal (I, Q) to a signal (I1, Q1) and a signal (I2, Q2) by applying the following equations (1) to (4):
I1 = {I+Q SQRT(4/a - 1)}/2 (1) Q1 = {Q-I SQRT(4/a - 1)}/2 (2) I2 = {I-Q SQRT(4/a - 1)}/2 (3) Q2 = {Q+I SQRT(4/a - 1)}/2 (4);
where, SQRT(x) refers to a square root of x, that is, a = (I2) + (Q2).
a first quadrature modulation means for quadrature modulating a carrier with said signal (I1, Q1) and generating a first modulated wave;
a second quadrature modulation means for quadrature modulating a carrier with said signal (I2, Q2) and generating a second modulated wave;
a first non-linear power amplifier for power amplifying said first modulated wave;
a second non-linear power amplifier for power amplifying said second modulated wave; and means for composing output signals of said first non-linear power amplifier and said second non-linear power amplifier.
means for converting a signal of said modulating signal (I, Q) to a signal (I1, Q1) and a signal (I2, Q2) by applying the following equations (1) to (4):
I1 = {I+Q SQRT(4/a - 1)}/2 (1) Q1 = {Q-I SQRT(4/a - 1)}/2 (2) I2 = {I-Q SQRT(4/a - 1)}/2 (3) Q2 = {Q+I SQRT(4/a - 1)}/2 (4);
where, SQRT(x) refers to a square root of x, that is, a = (I2) + (Q2).
a first quadrature modulation means for quadrature modulating a carrier with said signal (I1, Q1) and generating a first modulated wave;
a second quadrature modulation means for quadrature modulating a carrier with said signal (I2, Q2) and generating a second modulated wave;
a first non-linear power amplifier for power amplifying said first modulated wave;
a second non-linear power amplifier for power amplifying said second modulated wave; and means for composing output signals of said first non-linear power amplifier and said second non-linear power amplifier.
8 A method for transmitting a modulated wave with envelope variation, said method comprising steps of:
converting a signal of said modulating signal with envelope variation of which in-phase component signal is I and quadrature component signal is Q
to a signal of which in-phase component signal is I1, and quadrature component signal is Q1 and a signal of which in-phase component signal is I2, and quadrature component signal is Q2 that meet the following conditions (1) to (3):
(I1) + (Q1) = constant (1) (I2) + (Q2) = constant (2) Vector (I, Q) = Vector (I1, Q1) + Vector (I2, Q2) (3);
a first modulation step of modulating a carrier with said signal (I1, Q1) and generating a first modulated wave;
a second modulation step of modulating a carrier with said signal (I2, Q2) and generating a second modulated wave;
a first amplification step of power amplifying said first modulated wave;
a second amplification step of power amplifying said second modulated wave;
composing said first power amplified modulated wave and said second power amplified modulated wave;
band limiting a composed modulated wave; and transmitting a band limited modulated wave.
converting a signal of said modulating signal with envelope variation of which in-phase component signal is I and quadrature component signal is Q
to a signal of which in-phase component signal is I1, and quadrature component signal is Q1 and a signal of which in-phase component signal is I2, and quadrature component signal is Q2 that meet the following conditions (1) to (3):
(I1) + (Q1) = constant (1) (I2) + (Q2) = constant (2) Vector (I, Q) = Vector (I1, Q1) + Vector (I2, Q2) (3);
a first modulation step of modulating a carrier with said signal (I1, Q1) and generating a first modulated wave;
a second modulation step of modulating a carrier with said signal (I2, Q2) and generating a second modulated wave;
a first amplification step of power amplifying said first modulated wave;
a second amplification step of power amplifying said second modulated wave;
composing said first power amplified modulated wave and said second power amplified modulated wave;
band limiting a composed modulated wave; and transmitting a band limited modulated wave.
9 The method of claim 8, wherein said conversion step comprises a step of converting a signal of said modulating signal (I, Q) to a signal (I1, Q1) and a signal (I2, Q2) by applying the following equations (4) to (7):
I1 = {I+Q SQRT(4/a - 1)}/2 (4) Q1 = {Q-I SQRT(4/a - 1)}/2 (5) I2 = {I-Q SQRT(4/a - 1)}/2 (6) Q2 = {Q+I SQRT(4/a2 - 1)}/2 (7), where, SQRT(x) refers to a square root of x, that is, a2 = (I2)2 + (Q2)2.
I1 = {I+Q SQRT(4/a - 1)}/2 (4) Q1 = {Q-I SQRT(4/a - 1)}/2 (5) I2 = {I-Q SQRT(4/a - 1)}/2 (6) Q2 = {Q+I SQRT(4/a2 - 1)}/2 (7), where, SQRT(x) refers to a square root of x, that is, a2 = (I2)2 + (Q2)2.
The method of claim 8, wherein said first modulation step comprises a step of quadrature modulating a carrier with said signal (I1, Q1); and said second modulation step comprises a step of quadrature modulating a carrier with said signal (I2, Q2).
11 The method of claim 8, wherein said first amplification step comprises a step of non-linear power amplifying said first modulated wave;
and said second amplification step comprises a step of non-linear power amplifying said second modulated wave.
and said second amplification step comprises a step of non-linear power amplifying said second modulated wave.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6-301946 | 1994-12-06 | ||
| JP6301946A JPH08163189A (en) | 1994-12-06 | 1994-12-06 | Transmission circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2164465A1 true CA2164465A1 (en) | 1996-06-07 |
Family
ID=17903020
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002164465A Abandoned CA2164465A1 (en) | 1994-12-06 | 1995-12-05 | Converter for converting a modulating signal with variable envelope to two modulating signals without variable envelope, transmitter using the converter and method for transmitting a modulated wave with variable envelope |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US5784412A (en) |
| EP (1) | EP0716526B1 (en) |
| JP (1) | JPH08163189A (en) |
| KR (1) | KR100286722B1 (en) |
| AU (1) | AU705593B2 (en) |
| CA (1) | CA2164465A1 (en) |
| DE (1) | DE69534055T2 (en) |
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| US6032028A (en) * | 1996-04-12 | 2000-02-29 | Continentral Electronics Corporation | Radio transmitter apparatus and method |
| US6185259B1 (en) * | 1996-06-12 | 2001-02-06 | Ericsson Inc. | Transmitter/receiver for GMSK and offset-QAM |
| KR100221832B1 (en) * | 1996-11-19 | 1999-09-15 | 유기범 | Method for quadrature-quadrature amplitude modulation with constant amplitude characteristic and its apparatus |
| US6320914B1 (en) * | 1996-12-18 | 2001-11-20 | Ericsson Inc. | Spectrally efficient modulation using overlapped GMSK |
| US6415002B1 (en) * | 1998-04-07 | 2002-07-02 | Nortel Networks Limited | Phase and amplitude modulation of baseband signals |
| DE10101911B4 (en) | 2001-01-16 | 2004-03-18 | Interessengemeinschaft für Rundfunkschutzrechte GmbH Schutzrechtsverwertung & Co. KG. | Signal processing of an amplitude and / or phase modulated radio frequency signal |
| GB0205199D0 (en) | 2002-03-06 | 2002-04-17 | Univ Belfast | Modulator/transmitter apparatus and method |
| US6892057B2 (en) * | 2002-08-08 | 2005-05-10 | Telefonaktiebolaget Lm Ericsson (Publ) | Method and apparatus for reducing dynamic range of a power amplifier |
| JP2005151543A (en) * | 2003-10-20 | 2005-06-09 | Matsushita Electric Ind Co Ltd | Amplifier circuit |
| JP4388402B2 (en) * | 2004-03-31 | 2009-12-24 | 株式会社ルネサステクノロジ | Transmitter and mobile communication terminal using the same |
| US7327803B2 (en) | 2004-10-22 | 2008-02-05 | Parkervision, Inc. | Systems and methods for vector power amplification |
| US7355470B2 (en) | 2006-04-24 | 2008-04-08 | Parkervision, Inc. | Systems and methods of RF power transmission, modulation, and amplification, including embodiments for amplifier class transitioning |
| US7653146B2 (en) * | 2005-09-06 | 2010-01-26 | Liquid Xstream Systems Inc. | System and method for delivery of video, content on demand and IP packets |
| US7911272B2 (en) | 2007-06-19 | 2011-03-22 | Parkervision, Inc. | Systems and methods of RF power transmission, modulation, and amplification, including blended control embodiments |
| US9106316B2 (en) | 2005-10-24 | 2015-08-11 | Parkervision, Inc. | Systems and methods of RF power transmission, modulation, and amplification |
| US8013675B2 (en) | 2007-06-19 | 2011-09-06 | Parkervision, Inc. | Combiner-less multiple input single output (MISO) amplification with blended control |
| US8031804B2 (en) | 2006-04-24 | 2011-10-04 | Parkervision, Inc. | Systems and methods of RF tower transmission, modulation, and amplification, including embodiments for compensating for waveform distortion |
| EP2405277B1 (en) * | 2006-04-24 | 2014-05-14 | Parkervision, Inc. | Systems and methods of RF power transmission, modulation, and amplification |
| WO2008090598A1 (en) * | 2007-01-22 | 2008-07-31 | Panasonic Corporation | Amplifier |
| WO2008144017A1 (en) | 2007-05-18 | 2008-11-27 | Parkervision, Inc. | Systems and methods of rf power transmission, modulation, and amplification |
| WO2009005768A1 (en) | 2007-06-28 | 2009-01-08 | Parkervision, Inc. | Systems and methods of rf power transmission, modulation, and amplification |
| US8479374B2 (en) | 2010-12-14 | 2013-07-09 | Truesense Imaging, Inc. | Method of producing an image sensor having multiple output channels |
| US8773564B2 (en) | 2010-12-14 | 2014-07-08 | Truesense Imaging, Inc. | Image sensor with charge multiplication |
| US8553126B2 (en) | 2010-12-14 | 2013-10-08 | Truesense Imaging, Inc. | Image sensor with charge multiplication |
| US8493491B2 (en) | 2010-12-14 | 2013-07-23 | Truesense Imaging, Inc. | Methods for processing an image captured by an image sensor having multiple output channels |
| US8493492B2 (en) | 2010-12-14 | 2013-07-23 | Truesense Imaging, Inc. | Method of producing an image with pixel signals produced by an image sensor that includes multiple output channels |
| KR20140026458A (en) | 2011-04-08 | 2014-03-05 | 파커비전, 인크. | Systems and methods of rf power transmission, modulation, and amplification |
| EP2715867A4 (en) | 2011-06-02 | 2014-12-17 | Parkervision Inc | Antenna control |
| KR20160058855A (en) | 2013-09-17 | 2016-05-25 | 파커비전, 인크. | Method, apparatus and system for rendering an information bearing function of time |
| US11239990B2 (en) * | 2019-06-12 | 2022-02-01 | Infineon Technologies Ag | Phase error determination using two modulators |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3896395A (en) * | 1974-07-18 | 1975-07-22 | Bell Telephone Labor Inc | Linear amplification using quantized envelope components to phase reverse modulate quadrature reference signals |
| US3927379A (en) * | 1975-01-08 | 1975-12-16 | Bell Telephone Labor Inc | Linear amplification using nonlinear devices and inverse sine phase modulation |
| US4485358A (en) * | 1981-09-28 | 1984-11-27 | E-Systems, Inc. | Method and apparatus for pulse angle modulation |
| JPH0831886B2 (en) * | 1989-09-14 | 1996-03-27 | 松下電器産業株式会社 | Transmitter |
| US5990734A (en) * | 1998-06-19 | 1999-11-23 | Datum Telegraphic Inc. | System and methods for stimulating and training a power amplifier during non-transmission events |
-
1994
- 1994-12-06 JP JP6301946A patent/JPH08163189A/en active Pending
-
1995
- 1995-12-05 DE DE69534055T patent/DE69534055T2/en not_active Expired - Lifetime
- 1995-12-05 EP EP95119142A patent/EP0716526B1/en not_active Expired - Lifetime
- 1995-12-05 AU AU40246/95A patent/AU705593B2/en not_active Expired
- 1995-12-05 CA CA002164465A patent/CA2164465A1/en not_active Abandoned
- 1995-12-06 KR KR1019950047018A patent/KR100286722B1/en not_active IP Right Cessation
- 1995-12-06 US US08/568,142 patent/US5784412A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| AU4024695A (en) | 1996-06-13 |
| DE69534055T2 (en) | 2006-02-23 |
| US5784412A (en) | 1998-07-21 |
| EP0716526A3 (en) | 2000-12-20 |
| AU705593B2 (en) | 1999-05-27 |
| KR100286722B1 (en) | 2001-04-16 |
| EP0716526B1 (en) | 2005-03-09 |
| DE69534055D1 (en) | 2005-04-14 |
| EP0716526A2 (en) | 1996-06-12 |
| JPH08163189A (en) | 1996-06-21 |
| KR960027861A (en) | 1996-07-22 |
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| Date | Code | Title | Description |
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| EEER | Examination request | ||
| FZDE | Discontinued |