Quasi-linear multi-state digital modulation through non-linear amplifier arrays

• US 20040124916A1
• Filed: 12/31/2002
• Published: 07/01/2004
• Est. Priority Date: 12/31/2002
• Status: Active Grant

• Current Assignee: IIT Research Institute (Alion Science & Technology Corp.)
• Original Assignee: IIT Research Institute (Alion Science & Technology Corp.)
• Inventors: Kontson, Kalle R.
• Granted Patent: US 6,816,008 B2
• Time in Patent Office: Days
• US Class Current: 330/51
• CPC Class Codes: H03C 5/00 Amplitude modulation and angle modulation produced simultaneously or at will by the same modulating signal H03C7/00 takes precedence
• CPC Class Codes: H03F 1/32 Modifications of amplifiers to reduce non-linear distortion by negative feedback H03F1/34
• CPC Class Codes: H03F 2203/7215 the gated amplifier being switched on or off by a switch at the input of the amplifier
• 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 3/72 Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal

Abstract

At least one amplifier is selected from a first bank of non-linear amplifiers. At least one amplifier is selected from a second bank of non-linear amplifiers. The number of amplifiers selected from the first and second banks remains constant. Using the selected amplifiers, first and second components of a digital symbol are amplified using the first and second banks, respectively. The outputs produced by first and second banks are combined to produce an analog representation of the digital symbol.

Claims

1. A method of amplification, comprising:

selecting at least one amplifier from a first bank of non-linear amplifiers;

selecting at least one amplifier from a second bank of non-linear amplifiers, such that the number of amplifiers selected from the first and second banks remains constant;

using the selected amplifiers, amplifying first and second components of a digital symbol using the first and second banks, respectively; and

combining outputs produced by first and second banks to produce an analog representation of the digital symbol.

2. A method of amplification according to claim 1, wherein the first component is phase shifted by 90°

with respect to the second component.

3. A method of amplification according to claim 1, wherein at all times during operation, one and only one amplifier is selected from each of the first and second banks of amplifiers.

4. A method of amplification according to claim 1, wherein there are four amplifiers in the first bank of amplifiers and four amplifiers in the second bank of amplifiers.

5. A method of amplification according to claim 1, wherein

there are m amplifiers in the first bank of amplifiers,

there are n amplifiers in the second bank of amplifiers, and

each symbol carries r bits of data such that 2^r=(m*n).

6. A method of amplification according to claim 1, wherein

each amplifier of the first bank has a different gain characteristic,

each amplifier of the second bank has a different gain characteristic, and

the individual gain characteristics of the first bank are the same as the individual gain characteristics of the second bank.

7. A method of amplification according to claim 6, wherein the gain characteristics are selected so as to provide equal gain intervals between the amplifiers of each bank.

8. A method of amplification according to claim 1, wherein the amplifiers from the first and second banks are selected based on the gain characteristics of the amplifiers.

9. An amplifier device, comprising:

a first bank of non-linear amplifiers;

a second bank of non-linear amplifiers;

a selection unit to select at least one amplifier from each of the first and second banks of non-linear amplifiers such that

for each bank, the selected at least one amplifier produces an amplified output from a different component of a digital symbol, and

the number of amplifiers selected remains constant; and

a combination unit to combine the amplified outputs from the first and second banks.

10. An amplifier device according to claim 9, wherein there are four non-linear amplifiers in the first bank and four non-linear amplifiers in the second bank.

11. An amplifier device according to claim 9, wherein the first and second banks are formed on an application specific integrated circuit chip.

12. A wireless telephone, comprising:

a telephone body, a speaker, a microphone, an antenna, and a transceiver, the transceiver having a radio frequency amplifier comprising;

a first bank of non-linear amplifiers;

a second bank of non-linear amplifiers;

a selection unit to select at least one amplifier from each of the first and second banks of non-linear amplifiers such that

for each bank, the selected amplifier at least one amplifier produces an amplified output from a different component of a digital symbol, and

the number of amplifiers selected remains constant; and

a combination unit to combine the amplified outputs from the first and second banks.

13. An amplifier device, comprising:

a Q-phase premodulator to produce a Q-phase component;

an I-phase premodulator to produce an I-phase component;

at least one non-linear Q-phase amplifier to amplify the Q-phase component and produce an output;

at least one non-linear I-phase amplifier to amplify the I-phase component and produce an output; and

a combiner to combine the outputs of the Q-phase and I-phase amplifiers.

14. An amplifier device according to claim 13, wherein

the Q-phase component and the I-phase component contain substantially no amplitude information, and

amplitude information is added in the Q-phase and I-phase amplifiers.

15. An amplifier device according to claim 13, wherein the combiner produces an output signal that is fed to an antenna device with no intervening linear amplifiers.

16. An amplifier device according to claim 13, wherein the combiner produces an output signal that is sufficiently amplified for wireless transmission.

17. An amplifier device according to claim 13, further comprising an antenna device directly connected to combiner.