High efficiency linear power amplifier of plural frequency bands and high efficiency power amplifier

• US 5,973,557 A
• Filed: 10/15/1997
• Issued: 10/26/1999
• Est. Priority Date: 10/18/1996
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ishida, Kaoru, Enoki, Takashi, Kosugi, Hiroaki, Miyaji, Masayuki, Kato, Hidenobu, Morinaga, Yoichi
• Primary Examiner(s): Pascal, Robert
• Assistant Examiner(s): Nguyen, Patricia T.
• Application Number:
  US08/950,859
• Time in Patent Office: 741 Days
• Field of Search: 330/51, 330/126, 330/124 R, 330/124 D, 330/295, 330/302
• US Class Current: 330/51
• CPC Class Codes: H03F 1/02 Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
• CPC Class Codes: H03F 1/0277 Selecting one or more amplifiers from a plurality of amplifiers
• CPC Class Codes: H03F 2203/7236 the gated amplifier being switched on or off by putting into parallel or not, by choosing between amplifiers by (a ) switch(es)
• CPC Class Codes: H03F 2203/7239 the gated amplifier being switched on or off by putting into parallel or not, by choosing between amplifiers and shunting lines by one or more switch(es)
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H03F 3/72 Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal
• CPC Class Codes: H04B 1/0458 Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages matching circuits in general H03H
• CPC Class Codes: H04B 1/406 with more than one transmission mode, e.g. analog and digital modes
• CPC Class Codes: H04B 2001/045 with means for improving efficiency

Abstract

The invention presents a high efficiency linear power amplifier of plural frequency bands reduced in the number of parts and elements, simplified in the circuit construction, and saved in the circuit space, and in FIG. 1, signals entering from a common input terminal 1 in frequency bands A and B are matched in both frequency bands A and B in a wide band matching network 2, amplified in a pre-amplifier 3, put into a common terminal 4a of a switch circuit 4, and the signal in frequency band A is put into a changeover terminal 4b, matched in a matching network 5 and amplified in a post-amplifier 6, and its output is matched in a post-matching network 7 and sent out into an output terminal 8, while, similarly, the signal in frequency band B is put into other changeover terminal 4c of the switch circuit 4, matched in a matching network 9, amplified in a post-amplifier 10, and its output is matched in a post-matching network 11 and is sent out into an output terminal 12.

The invention also presents a power amplifier capable of maintaining a similar high efficiency characteristic if the output power is lowered from the output power of maximum efficiency, and in FIG. 10, first and second power amplifiers 113, 114 are disposed in parallel, and a necessary number of power amplifiers are connected depending on a required output power by switch circuits 115 to 118, and the power source is turned on only in the connected power amplifiers, while the other power amplifiers are turned off, and therefore by the lowering portion of the output power, the current consumption decreases in proportion, so that the equivalent high efficiency operation same as in the case maximum efficiency is realized.

Claims

1. A high efficiency linear power amplifier of plural frequency bands comprising:

pre-amplifying means connected to an input terminal for receiving signals in plural frequency bands, for amplifying the input signals of plural frequency bands,

changeover means of plural frequency bands for changing over the output of the pre-amplifying means for issuing to any one of plural changeover terminals, and

a plurality of post-amplifying blocks connected to each one of the plural changeover terminals of the changeover means of plural frequency bands,

wherein each one of said plurality of post-amplifying blocks comprises single frequency band matching means for matching impedance between the output of the pre-amplifying means and input of a below-described post-amplifying means in a single frequency band, post-amplifying means for amplifying the output signal of the single frequency band matching means, post-matching means connected to the output of the post-amplifying means for matching the output impedance of the post-amplifying means in a single frequency band, and output terminal for issuing the output signal of the post-matching means.

2. A high efficiency linear power amplifier of plural frequency bands of claim 1, wherein the output of the pre-amplifying means is connected to the changeover means of plural frequency bands through auxiliary matching means, and the auxiliary matching means matches the impedance of the inputs of the pre-amplifying means and post-amplifying means in the operating frequency band through cooperation with the element of the single frequency band matching means in each frequency band.

3. A high efficiency linear power amplifier of plural frequency bands of claim 1 wherein wide band matching means for matching the impedance between the output of the pre-stage and the input of the pre-amplifying means in plural frequency bands is provided between the input terminal and the pre-amplifying means.

4. A high efficiency linear power amplifier of plural frequency bands of claim 2, wherein the auxiliary matching means is a grounded capacitance or low impedance line, and the single frequency band matching means is an inductance.

5. A high efficiency linear power amplifier of plural frequency bands of claim 3, wherein the wide band matching means is a combination of a set of inductance and capacitance and a negative feedback amplifier.

6. A high efficiency linear power amplifier of plural frequency bands of claim 1, wherein at least whole constituent elements are composed on a same semiconductor chip.

7. A high efficiency linear power amplifier of plural frequency bands of claim 1, wherein at least the pre-amplifying means, changeover means of plural frequency bands, plurality of single frequency band matching means, and plurality of post-amplifying means are composed on a same semiconductor chip.

8. A high efficiency linear power amplifier of plural frequency bands of claim 2, wherein at least the pre-amplifying means, auxiliary matching means, changeover means of plural frequency bands, plurality of single frequency band matching means, and plurality of post-amplifying means are composed on a same semiconductor chip.

9. A high efficiency linear power amplifier of plural frequency bands of claim 3, wherein at least the wide band matching means, pre-amplifying means, changeover means of plural frequency bands, plurality of single frequency band matching means, and plurality of post-amplifying means are composed on a same semiconductor chip.

10. A high efficiency linear power amplifier of plural frequency bands of claim 3, wherein at least the wide band matching means, pre-amplifying means, auxiliary matching means, changeover means of plural frequency bands, plurality of single frequency band matching means, and plurality of post-amplifying means are composed on a same semiconductor chip.

11. A high efficiency linear power amplifier of plural frequency bands of claim 1, wherein at least the pre-amplifying means and changeover means of plural frequency bands are composed on a same semiconductor chip.

12. A high efficiency linear power amplifier of plural frequency bands of claim 2, wherein at least the pre-amplifying means, auxiliary matching means, and changeover means of plural frequency bands are composed on a same semiconductor chip.

13. A high efficiency linear power amplifier of plural frequency bands of claim 3, wherein at least the wide band matching means, pre-amplifying means, and changeover means of plural frequency bands are composed on a same semiconductor chip.

14. A high efficiency linear power amplifier of plural frequency bands of claim 3, wherein at least the wide band matching means, pre-amplifying means, auxiliary matching means, and changeover means of plural frequency bands are composed on a same semiconductor chip.

21. A wireless appliance comprising the high efficiency linear power amplifier of plural frequency bands of claim 1.

23. A high efficiency linear power amplifier of plural frequency bands of claim 1, wherein said post amplifying means includes at least two power amplifiers, at least two power source changeover means for turning on or off the power source of each one of the power amplifiers, a first common terminal, input branching means having a switching function between the input terminals of each one of the power amplifiers from the first common terminal, first impedance converting means for converting the impedance of the first common terminal, a second common terminal, output selecting means having a switching function between the output terminals of each one of the power amplifiers from the second common terminal, second impedance converting means for converting the impedance of the second common terminal, and control means for controlling the input branching means and output selecting means depending on a required output power to connect a necessary number of the power amplifiers, converting the input impedance of the first common terminal by the first impedance converting means depending on the connection state of the power amplifiers, converting the impedance of the second common terminal by the second impedance converting means depending on the connection state of the power amplifiers, turning on those power source changeover means corresponding to the connected power amplifiers, and turning off the others.

15. A high efficiency power amplifier comprising at least two power amplifiers, at least two power source changeover means for turning on or off the power source of each one of the power amplifiers, a first common terminal, input branching means having a switching function between the input terminals of each one of the power amplifiers from the first common terminal, first impedance converting means for converting the impedance of the first common terminal, a second common terminal, output selecting means having a switching function between the output terminals of each one of the power amplifiers from the second common terminal, second impedance converting means for converting the impedance of the second common terminal, and control means for controlling the input branching means and output selecting means depending on a required output power to connect a necessary number of the power amplifiers, converting the input impedance of the first common terminal by the first impedance converting means depending on the connection state of the power amplifiers, converting the impedance of the second common terminal by the second impedance converting means depending on the connection state of the power amplifiers, turning on those power source changeover means corresponding to the connected power amplifiers, and turning off the others.

20. A high efficiency power amplifier of claim 15, wherein at least one of the power amplifiers is a power amplifier having a different output power.

16. A high efficiency power amplifier comprising at least two power amplifiers, each transmission line having one end connected in series to the output terminal of each one of the power amplifiers, and other end connected commonly, at least two power source changeover means for turning on or off the power source of each one of the power amplifiers, a common terminal, input branching means having a switching function between the input terminals of each one of the power amplifiers from the common terminal, first impedance converting means for converting the impedance of the common terminal, second impedance converting means for converting the impedance, being connected to the common junction of the transmission line, and control means for controlling the input branching means depending on a required output power to connect a necessary number of the power amplifiers, converting the input impedance of the common terminal by the first impedance converting means depending on the connection state of the power amplifiers, converting the impedance by the second impedance converting means depending on the connection state of the power amplifiers, turning on those power source changeover means corresponding to the connected power amplifiers, and turning off the others, wherein the impedance as seen from the output side of each transmission line to the input side when the power source changeover means of each one of the power amplifiers is turned off is set so as to be a high impedance.

17. A high efficiency power amplifier comprising at least two power amplifiers, a transmission line, at least two power source changeover means for turning on or off the power source of each one of the power amplifiers, a first common terminal, input branching means having a switching function between the input terminal of each one of the power amplifiers and the input terminal of the transmission line from the first common terminal, first impedance converting means for converting the impedance of the first common terminal, a second common terminal, output selecting means having a switching function between the output terminal of each one of the power amplifiers and the output terminal of the transmission line from the second common terminal, second impedance converting means for converting the impedance of the second common terminal, and control means for controlling the input branching means and output selecting means depending on a required output power to connect a necessary number of the power amplifiers, converting the input impedance of the first common terminal by the first impedance converting means depending on the connection state of the power amplifiers, converting the impedance of the second common terminal by the second impedance converting means depending on the connection state of the power amplifiers, turning on those power source changeover means corresponding to the connected power amplifiers, and turning off the others, or when not necessary to amplify, controlling the input branching means and output selecting means to connect the transmission line, and turning off all of the power source changeover means of the power amplifiers.

18. A high efficiency power amplifier comprising a power amplifier, a first transmission line, a second transmission line having one end connected in series to the output terminal of the power amplifier, and other end connected commonly with the output end of the first transmission line, power source changeover means for turning on or off the bias of the power amplifier, a common terminal, input branching means for changing over the input terminal of the power amplifier and the input terminal of the first transmission line from the common terminal, and control means for controlling the input branching means to connect the power amplifier, and turning on the power source changeover means, at the time of high output, or controlling the input branching means to connect the first transmission line, and turning off the power source changeover means, at the time of low output, wherein the impedance as seen from the output side of second transmission line to the input side when the power source changeover means of the power amplifier is turned off is set so as to be a high impedance, and the impedance as seen from the output side of the first transmission line to the input side when the first transmission line is cut off is set to be a high impedance.

19. A high efficiency power amplifier comprising at least two power amplifiers, a first transmission line, each second transmission line having one end connected in series to the output terminal of each one of the power amplifiers and other end connected commonly to the output end of the first transmission line, at least two power source changeover means for turning on or off the power source of each one of the power amplifiers, a common terminal, input branching means having a switching function between the input terminal of each one of the power amplifiers and the input terminal of the first transmission line from the common terminal, a first impedance converting means for converting the impedance of the common terminal, second impedance converting means for converting the impedance, being connected at the common junction of the first and second transmission lines, and control means for controlling the input branching means depending on a required output power to connect a necessary number of the power amplifiers, converting the input impedance of the common terminal by the first impedance converting means depending on the connection state of the power amplifiers, converting the impedance by the second impedance converting means depending on the connection state of the power amplifiers, turning on those power source changeover means corresponding to the connected power amplifiers, and turning off the others, or when not necessary to amplify, controlling the input branching means to connect the first transmission line, and turning off all of the power source changeover means of the power amplifiers, wherein the impedance as seen from the output side of each second transmission line to the input side when the power source changeover means of each one of the power amplifiers is turned off is set so as to be a high impedance, and the impedance as seen from the output side of the first transmission line to the input side when the first transmission line is cut off is set to be a high impedance.

22. A high efficiency power amplifier comprising at least two power amplifiers,

at least two power source changeover means for turning on or off the power source of each one of the power amplifiers,

a first common terminal,

input branching means having a switching function between the input terminals of each one of the power amplifiers from the first common terminal,

first impedance converting means for converting the impedance of the first common terminal,

a second common terminal,

output selecting means having a switching function between the output terminals of each one of the power amplifiers from the second common terminal,

second impedance converting means for converting the impedance of the second common terminal, and

control means for controlling the input branching means and output selecting means depending on a required output power to connect a necessary number of the power amplifiers, converting the input impedance of the first common terminal by the first impedance converting means depending on the connection state of the power amplifiers, converting the impedance of the second common terminal by the second impedance converting means depending on the connection state of the power amplifiers, turning on those power source changeover means corresponding to the connected power amplifiers, and turning off the others,

wherein the first and second impedance converting means each has a transformer for changing the turn ratio.