JP4709447B2 - Amplifying device and transmitter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an amplification device and a transmitter. In particular, the present invention relates to an amplitude modulation type transmitter based on digital modulation control.
[0002]
[Prior art]
Conventionally, as an amplitude modulation method by digital modulation control, for example, there is a method disclosed in Japanese Unexamined Patent Publication No. 2000-232380. In this method, a plurality of power amplifiers are directly turned on and off by digital signals, and all information (bits) of the modulated signal is modulated and amplified.
[0003]
[Problems to be solved by the invention]
However, the conventional modulation scheme has a problem that distortion occurs in the amplitude modulation signal output from the transmitter due to an error with respect to the ideal value of the amplification factor of the plurality of power amplifiers. The error also changes due to power supply voltage fluctuations, temperature changes, aging degradation, and the like.
[0004]
Therefore, in the conventional amplitude modulation method using digital modulation control, there is a problem that stable operation is hindered by distortion generated in the amplitude modulation signal output from the transmitter. Therefore, an object of the present invention is to provide an amplifying apparatus and a transmitter that can solve the above-described problems. This object is achieved by a combination of features described in the independent claims. The dependent claims define further advantageous specific examples of the present invention.
[Means for Solving the Problems]
[0005]
That is, according to a first aspect of the present invention, there is provided an amplifying apparatus that amplifies the amplitude of an amplified signal based on a first magnification signal that specifies an amplification factor of the amplified signal and a second magnification signal, The first magnification signal includes a first amplification unit that outputs the first amplification signal obtained by amplifying the amplitude of the amplified signal based on the first magnification signal, and a correction value that corrects the amplitude of the first amplification signal. A second amplification signal that outputs a second amplified signal obtained by amplifying the amplitude of the signal to be amplified based on the correction value storage unit that stores the value corresponding to each of the indicated values, the correction value, and the second magnification signal; And an combining unit that combines the first amplified signal and the second amplified signal and outputs the synthesized signal as an output signal of the amplifying device.
[0006]
Moreover, it is preferable that the amplifying device further includes a correction value updating unit that corrects the correction value based on the output signal of the amplifying device and the first magnification signal.
[0007]
According to the second aspect of the present invention, a transmitter that outputs an amplitude-modulated signal based on a modulated signal, a carrier-wave signal generating unit that outputs a carrier-wave signal having a predetermined period, and the amplitude of the modulated signal A signal obtained by amplifying the amplitude of the carrier signal with an amplification factor based on the conversion unit that outputs the first magnification signal and the second magnification signal, the first magnification signal, and the second magnification signal is used as the amplitude modulation signal. A modulation amplification unit for outputting, wherein the modulation amplification unit amplifies the amplitude of the carrier signal based on the first magnification signal, and outputs a first amplification signal; and the first amplification signal A correction value storage unit that stores a correction value for correcting the amplitude of the carrier wave signal corresponding to each of the values indicated by the first magnification signal, the correction value, and the amplitude of the carrier signal based on the second magnification signal A second booster that outputs a second amplified signal It provides a section, the first amplified signal and the by synthesizing the second amplified signal transmitter, comprising a combining unit for outputting as the amplitude modulated signal.
[0008]
The above summary of the invention does not enumerate all necessary features of the present invention, and sub-combinations of these feature groups can also be the invention.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the claimed invention, and all combinations of features described in the embodiments are the solution of the invention. It is not always essential to the means.
[0010]
FIG. 1 shows a transmitter 100 according to an embodiment of the present invention. The transmitter 100 is a transmitter that outputs an amplitude modulation signal obtained by amplifying the amplitude of the carrier signal CWS with an amplification factor based on the modulation signal, and includes a carrier signal generation unit 102, a conversion unit 104, and a modulation amplification unit 106. Prepare. The carrier signal generation unit 102 outputs a carrier signal CWS having a predetermined period and carrying information based on the modulation signal. The conversion unit 104 outputs the first magnification signal HBS and the second magnification signal LBS based on the amplitude of the modulation signal AMS.
[0011]
The conversion unit 104 outputs a modulated signal amplifier 222 that outputs an amplified modulated signal obtained by amplifying the amplitude of the modulated signal AMS, and outputs a signal obtained by A / D converting the amplified modulated signal as a magnification designation signal MAS that is an 11-bit digital signal. And a first A / D converter 224. The modulation signal amplifier 222 preferably amplifies the amplitude of the modulation signal AMS to an input amplitude value required by the modulation amplification unit 106. The first A / D converter 224 outputs the upper 5 bits of the magnification designation signal MAS as the first magnification signal HBS and outputs the lower 6 bits as the second magnification signal LBS.
[0012]
The modulation amplification unit 106 receives the carrier signal CWS, the first magnification signal HBS, and the second magnification signal LBS, and the amplitude of the carrier signal CWS with an amplification factor based on the first magnification signal HBS and the second magnification signal LBS Is amplified as an amplitude modulation signal AAS. The modulation amplification unit 106 includes a first amplification unit 202, a correction value storage unit 206, a second amplification unit 204, and a synthesis unit 208.
[0013]
The first amplifying unit 202 outputs a first amplified signal EBS obtained by amplifying the amplitude of the carrier signal CWS based on the first magnification signal HBS. The correction value storage unit 206 stores a correction value for correcting the amplitude of the first amplified signal EBS in correspondence with each value indicated by the first magnification signal HBS.
[0014]
Second amplification section 204 outputs second amplified signal BBS obtained by amplifying the amplitude of carrier wave signal CWS based on the correction value and second magnification signal LBS. The second amplification unit 204 preferably outputs the second amplified signal BBS having an amplitude smaller than that of the first amplified signal EBS. The synthesizer 208 synthesizes the first amplified signal EBS and the second amplified signal BBS and outputs them as an amplitude modulation signal AAS.
[0015]
The modulation amplification unit 106 preferably further includes a correction value update unit 210 that corrects the correction value stored in the correction value table 206 based on the amplitude modulation signal AAS and the first magnification signal HBS. In the present embodiment, the modulation amplification unit 106 further includes a correction value update unit 210 that supplies a correction value correction signal CCS based on the amplitude modulation signal AAS and the first magnification signal HBS to the correction value storage unit 206. The correction value storage unit 206 corrects the correction value based on the correction value correction signal CCS. The correction value storage unit 206 may store the value 0 as the initial value of the correction value. Hereinafter, the first amplifying unit 202, the second amplifying unit 204, the correction value updating unit 210, the correction value storing unit 206, and the synthesizing unit 208 that the modulation amplifying unit 106 has will be described in detail.
[0016]
The first amplification unit 202 preferably includes a plurality of first amplifiers 322 and an equal power PA selection unit 324. In the present embodiment, the first amplification unit 202 includes 26 first amplifiers (322-1 to 322-26) and an equal power PA selection unit 324. The first amplifiers (322-1 to 322-26) are power amplifiers having the same amplification factor.
[0017]
Each of the first amplification units 202 receives one first operation signal ESS from the plurality of first operation signals (ESS-1 to ESS-26) output from the equal power PA selection unit 324. The first amplifier 322 receives one first operation signal ESS and a carrier signal CWS, and amplifies the amplitude of the carrier signal CWS with a predetermined amplification factor when the first operation signal ESS has a predetermined logical value. It is preferable to output the first amplified signal EBS. The first amplifier 322-n (n is an integer satisfying 1 ≦ n ≦ 26) receives the first operation signal ESS-n and the carrier signal CWS, and the logical value of the first operation signal ESS-n is When it is 1, the first amplified signal EBS-n obtained by amplifying the amplitude of the carrier signal CWS with a predetermined amplification factor is output.
[0018]
The equal power PA selection unit 324 selects the number of first amplifiers 322 represented by the first magnification signal HBS from the plurality of first amplifiers 322. Here, the number represented by the digital signal refers to a numerical value obtained by converting a value represented by the digital signal as a binary number into a decimal number. For example, when the value indicated by the digital signal as a binary number is “01001”, the number represented by the digital signal is nine. The equal power PA selection unit 324 outputs a plurality of first operation signals ESS based on the first magnification signal HBS. The equal power PA selection unit 324 selects the number of first operation signals ESS represented by the first magnification signal HBS, which is a digital signal, from among the plurality of first operation signals ESS, and outputs a logical value 1. The equal power PA selection unit 324 sets the logical value of the first operation signal ESS to 1 to select the first amplifier 322 that receives the first operation signal ESS.
[0019]
In the present embodiment, the equal power PA selection unit 324 receives the first magnification signal HBS that is a 5-bit digital signal, and generates the first operation signal (ESS-1 to ESS-26) based on the first magnification signal HBS. Output. When the number represented by the first magnification signal HBS is k (k is an integer satisfying 1 ≦ k ≦ 26), the equal power PA selection unit 324 outputs the first operation signal (ESS-1 to ESS-k). Outputs a logical value of 1. When the number represented by the first magnification signal HBS is 0, the equal power PA selection unit 324 outputs a logical value 0 as the first operation signal (ESS-1 to ESS-26). For example, when the value indicated by the first magnification signal HBS as a binary number is “01001”, the equal power PA selection unit 324 outputs a logical value 1 as one operation signal (ESS-1 to ESS-9).
[0020]
The second amplification unit 204 preferably includes a plurality of second amplifiers 342 and a binary PA selection unit 344. In the present embodiment, the second amplification unit 204 includes six second amplifiers (342-1 to 342-6) and a binary PA selection unit 344. The second amplifier 342-k ′ (k ′ is an integer satisfying 1 ≦ k ′ ≦ 6) is (1/2) ^{k ′} × A × when the amplification factor of the first amplifier 322 is A. This is a power amplifier having an amplification factor α (α is a predetermined number). In order for the second amplifying unit 204 to correct the amplitude of the first amplified signal EBS by the second amplified signal BBS, the predetermined number α is preferably 1 or more.
[0021]
Each of the second amplification units 204 receives one second operation signal BSS from the plurality of second operation signals (BSS-1 to BSS-6) output from the binary PA selection unit 344. The second amplifier 342 receives one second operation signal BSS and the carrier signal CWS, and amplifies the amplitude of the carrier signal CWS with a predetermined amplification factor when the second operation signal BSS has a predetermined logical value. It is preferable to output the second amplified signal BBS. The second amplifier 342-n ′ (n ′ is an integer satisfying 1 ≦ n ′ ≦ 6) receives the second operation signal BSS-n ′ and the carrier signal CWS, and receives the second operation signal BSS-n. When the logical value of “1” is 1, the second amplified signal BBS-n ′ obtained by amplifying the amplitude of the carrier wave signal CWS with a predetermined amplification factor is output.
[0022]
The binary PA selection unit 344 selects a predetermined second amplifier 342 from the plurality of second amplifiers 342 based on the second magnification signal LBS and the correction value signal CVS. The binary PA selection unit 344 outputs a plurality of second operation signals BSS based on the second magnification signal LBS and the correction value signal CVS. The binary PA selection unit 344 selects a predetermined second operation signal BSS from the plurality of second operation signals BSS based on the second magnification signal LBS and the correction value signal CVS, and outputs a logical value 1. The binary PA selection unit 344 selects the second amplifier 342 that receives the second operation signal BSS by setting the logical value of the second operation signal BSS to 1.
[0023]
In the present embodiment, the binary PA selection unit 344 includes a multiplier 346 and an adder 348. The multiplier 346 outputs a number obtained by multiplying the number represented by the second magnification signal LBS and the predetermined number 1 / α as the divided second magnification signal DLBS. The adder 348 outputs the sum of the number represented by the second magnification signal DLBS to be divided and the correction value represented by the correction value signal CVS as a 6-bit digital signal. The binary PA selection unit 344 outputs the 6-bit digital signal as second operation signals (BSS-1 to BSS-6). That is, the binary PA selection unit 344 outputs the logical value of the n′-th bit counted from the higher order of the 6-bit digital signal as the second operation signal BSS-n ′.
[0024]
In the present embodiment, the correction value update unit 210 includes a detection unit 366, a second A / D converter 364, a timing adjustment unit 370, a delay signal generation unit 362, and a correction value correction signal generation unit 368. The detector 366 receives the amplitude modulation signal AAS and outputs a demodulated signal of the amplitude modulation signal AAS. The second A / D converter 364 outputs a feedback signal FBS that is a digital signal obtained by A / D converting the demodulated signal. In the present embodiment, the second A / D converter 364 outputs a feedback signal FBS that is an 11-bit digital signal obtained by A / D converting the demodulated signal. The timing adjustment unit 370 adjusts the timing of A / D conversion performed by the second A / D converter 364. For example, the timing adjustment unit 370 adjusts the sample timing of A / D conversion performed by the second A / D converter 364.
[0025]
The delay signal generation unit 362 outputs a delay magnification instruction signal DMS obtained by delaying the magnification designation signal MAS by a predetermined delay time. The delay signal generation unit 362 preferably outputs a delay magnification instruction signal DMS obtained by delaying the magnification designation signal MAS by a delay time equal to the phase difference between the feedback signal FBS and the magnification designation signal MAS.
[0026]
In the present embodiment, the delay signal generation unit 362 outputs the upper 5 bits of the delay magnification instruction signal DMS as the delayed first magnification signal DHS and outputs the lower 6 bits as the delayed second magnification signal DLS. That is, the delay signal generation unit 362 is a delayed first magnification signal DHS obtained by delaying the first magnification signal HBS by the predetermined time, and a delayed second magnification signal DLS obtained by delaying the second magnification signal LBS by the predetermined time. Is output.
[0027]
The correction value correction signal generation unit 368 outputs a correction value correction signal CCS based on the delay magnification instruction signal DMS and the feedback signal FBS. The correction value update unit 210 may output a correction value correction signal CCS having a bit number equal to the bit number of the second magnification signal LBS. In the present embodiment, the correction value update unit 210 outputs the difference between the number represented by the feedback signal FBS and the number represented by the delay magnification instruction signal DMS as a correction value correction signal CCS that is a 6-bit digital signal.
[0028]
The correction value storage unit 206 preferably outputs the correction value corresponding to the first magnification signal HBS as the correction value signal CVS having the number of bits equal to the number of bits of the second magnification signal LBS. In this embodiment, the correction value storage unit 206 outputs the correction value as a correction value signal CVS which is a 6-bit digital signal.
The correction value storage unit 206 further receives the correction value correction signal CCS and the delayed first magnification signal DHS. The correction value storage unit 206 preferably generates a new correction value corresponding to the first magnification signal HBS indicating a value equal to the value indicated by the delayed first magnification signal DHS, based on the correction value correction signal CCS.
[0030]
In the present embodiment, the correction value storage unit 206 represents the old correction value, which is a correction value corresponding to the first magnification signal HBS indicating a value equal to the value indicated by the updated first magnification signal CHS, and the correction value correction signal CCS. The sum with the number is generated as the new correction value. The correction value storage unit 206 stores the new correction value instead of the old correction value.
[0031]
The combining unit 208 is connected to each of the first amplifiers (322-1 to 322-26) and each of the second amplifiers (342-1 to 342-6) by transformer coupling. The synthesizer 208 includes a first amplified signal (EBS-1 to EBS-26) output from each of the first amplifiers (322-1 to 322-26) and a second amplifier (342-) via the transformer coupling. 1 to 342-6) receive the second amplified signal (BBS-1 to BBS-6) output from each. The synthesizer 208 connects the respective secondary coils in the transformer coupling in series. The synthesizer 206 grounds one end of both ends of the secondary coils connected in series, and outputs a signal generated at the other end as the amplitude modulation signal AAS. The synthesizer 206 may output, for example, the amplitude modulation signal AAS as an antenna output.
[0032]
According to the present embodiment, the transmitter 100 corrects the amplitude of the first amplified signal EBS output from the first amplifying unit 202 with the second amplified signal BBS output from the second amplifying unit 204. Thus, the transmitter 100 can compensate for distortion of the output amplitude modulation signal AAS and perform stable transmission.
[0033]
Further, the transmitter 100 may be applied to a wireless transceiver. The radio transceiver may be a base station or a mobile station, for example. In this case, the wireless transceiver includes an antenna, a shared unit, a receiving unit, and a transmitting unit. The shared unit is electrically connected to the antenna, the receiving unit, and the transmitting unit, and removes the interaction between the transmission signal and the received signal when the antenna transmits and receives signals. The receiving unit is a demodulation circuit that demodulates a received signal. The transmitter is the transmitter 100. Also in this case, the radio transceiver can compensate for distortion generated in the amplitude modulation signal output from the transmission unit and perform stable transmission.
[0034]
As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. Various modifications or improvements can be added to the above embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.
【The invention's effect】
[0035]
As is apparent from the above description, according to the present invention, distortion generated in an amplitude modulation signal output from a transmitter can be reduced in an amplitude modulation type transmitter using digital modulation control.
[Brief description of the drawings]
FIG. 1 shows a transmitter 100 according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 100 ... Transmitter, 102 ... Carrier wave signal generation unit, 104 ... Conversion unit, 106 ... Modulation amplification unit, 202 ... First amplification unit, 204 ... Second amplification unit, 206 ... Correction value storage unit, 208 ... Synthesis unit, 210 ... Correction value update unit, 222 ... Modulation signal amplifier, 224 ... First A / D converter, 322 ... First amplifier , 324 ... Equal power PA selection unit, 342 ... Second amplifier, 344 ... Binary PA selection unit, 346 ... Multiplier, 348 ... Adder, 362 ... Delay signal generation unit , 364 ... 2nd A / D converter, 366 ... detector, 368 ... update correction value signal generator, 370 ... timing adjuster,

Claims (4)

A amplifier that amplifies the amplitude of the amplified signal based on the first ratio signal and the second magnification signal,
A plurality of first amplifiers in order, the number of first amplifiers represented by the first magnification signal selected from the plurality of first amplifiers according to the order, and the amplified by the selected first amplifier; A first amplifier for outputting a first amplified signal obtained by amplifying the amplitude of the signal;
A correction value storage for storing a correction value for correcting the amplitude of the first amplified signal corresponding to the number represented by the first magnification signal;
A plurality of second amplifiers having a smaller amplification factor than the plurality of first amplifiers, the second magnification signal designating a second amplifier to be selected among the plurality of second amplifiers; and the first magnification signal The second amplifier is selected based on the correction value signal designating the second amplifier having an amplification factor corresponding to the correction value stored in the correction value storage unit corresponding to the number represented by A second amplifier for outputting a second amplified signal obtained by amplifying the amplitude of the signal to be amplified by an amplifier;
Said first amplified signal and combined to amplified apparatus Ru and a combining unit for outputting as an output signal of the amplifying device and said second amplified signal. And said output signal of said amplifier, based on the first ratio signal, the correction value according to 請 Motomeko 1 further Ru a correction value updating unit for updating said stored correction value in the storage unit amplification apparatus. The correction value updating unit is configured to determine a delay number based on a difference between a number represented by a feedback signal based on the output signal and a number represented by a delayed first magnification signal obtained by delaying the first magnification signal by a predetermined time. The amplification device according to claim 2, wherein the correction value corresponding to the number represented by the first magnification signal indicating a value equal to the number represented by the one magnification signal is updated. A transmitter for outputting an amplitude modulation signal based on a modulation signal,
A carrier wave signal generator for outputting a carrier wave signal having a predetermined period;
A conversion unit that outputs a first magnification signal and a second magnification signal based on the amplitude of the modulation signal;
Comprising a first magnification signal, and the modulation amplifier for outputting a signal amplifying the amplitude of the second magnification signal and the based have been the carrier signal as the amplitude-modulated signal,
The modulation amplification unit includes:
A plurality of first amplifiers in order, the number of first amplifiers represented by the first magnification signal is selected from the plurality of first amplifiers according to the order, and the carrier wave is selected by the selected first amplifier. A first amplifier for outputting a first amplified signal obtained by amplifying the amplitude of the signal;
A correction value storage for storing a correction value for correcting the amplitude of the first amplified signal corresponding to the number represented by the first magnification signal;
A plurality of second amplifiers having a smaller amplification factor than the plurality of first amplifiers, the second magnification signal designating a second amplifier to be selected among the plurality of second amplifiers; and the first magnification signal The second amplifier is selected based on the correction value signal designating the second amplifier having an amplification factor corresponding to the correction value stored in the correction value storage unit corresponding to the number represented by A second amplifying unit that outputs a second amplified signal obtained by amplifying the amplitude of the carrier wave signal by an amplifier ;
Said first amplified signal and the second amplified signal and combined to Shin machine feed that a synthesizing unit for outputting as the amplitude modulated signal.

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