PHASED ARRAY WEIGHTING FOR POWER EFFICIENCY IMPROVEMENT WITH HIGH PEAK-TO-AVERAGE POWER RATIO SIGNALS

• US 20160285481A1
• Filed: 03/25/2015
• Published: 09/29/2016
• Est. Priority Date: 03/25/2015
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel IP Corporation (Intel Corporation)
• Inventors: Cohen, Emanuel
• Granted Patent: US 10,027,354 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 21/293 one unit or more being an array of identical aerial elements adaptive arrays H01Q3/2605
• CPC Class Codes: H01Q 3/34 by electrical means active lenses or reflecting arrays H01Q3/46
• CPC Class Codes: H01Q 3/38 the phase-shifters being digital
• 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 3/24 of transmitter output stages
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 1/0483 Transmitters with multiple parallel paths
• CPC Class Codes: H04B 2001/0408 with power amplifiers
• CPC Class Codes: H04B 2001/045 with means for improving efficiency
• CPC Class Codes: H04B 7/0465 taking power constraints at power amplifier or emission constraints, e.g. constant modulus, into account
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A phased array includes a number of transmission units with an unequal array of power amplifiers for receiving or transmitting input signals at millimeter wave frequencies. The phase array transmits millimeter waves in air to reconstruct original phase-and amplitude signals by combining the signals from the unequal array of power amplifiers. The unequal array of power amplifiers comprises power amplifiers having a higher peak power than other power amplifiers of the array. The power amplifiers can also have different transmission powers from one another.

Claims

1. A phased array communication system comprising:

an array of transmission units comprising;

an unequal array of power amplifiers comprising a first power amplifier and a second power amplifier having different output powers and different saturation power levels between the first power amplifier and the second power amplifier; and

an array of antenna ports, coupled to the unequal array of power amplifiers, configured to receive a plurality of input signals comprising different phases and gains among input signals of the plurality of input signals;

wherein the array of transmission units is configured to generate over the air a combined signal by transmitting at least two signal outputs at a predetermined angle over the air to reconstruct an amplitude and phase modulated signal of at least one signal of the plurality of input signals.

2. The phased array communication system of claim 1, further comprising:

a weighting component configured to weight combinations of power amplifiers of the unequal array of power amplifiers based on an efficiency power boosting range.

3. The phased array communication system of claim 1, wherein the unequal array of power amplifiers comprises a first number of first power amplifiers and a second number of second power amplifiers that comprise a higher saturation power level than the first number of first power amplifiers.

4. The phased array communication system of claim 3, wherein the first number of first power amplifiers is greater than the second number of second power amplifiers based on a predetermined ratio.

5. The phased array communication system of claim 1, further comprising:

an adaptation component configured to selectively activate the unequal array of power amplifiers to process the at least one signal of the plurality of input signals via the array of antenna ports based on a set of predetermined criteria.

6. The phased array communication system of claim 5, wherein the set of predetermined criteria comprises at least one of a signal peak of the at least one signal, an efficiency of a combination of at least two power amplifiers of the unequal array of power amplifiers, an output power of a power amplifier of the unequal array of power amplifiers, or a saturation power level of the power amplifier.

7. The phased array communication system of claim 5, wherein the adaptation component is further configured to select a combination of power amplifiers from the unequal array of power amplifiers to increase a transmission power efficiency corresponding to a transmission of the at least one signal and an overall efficiency of the array of transmission units.

8. The phased array communication system of claim 5, wherein the adaptation component is further configured to generate a tradeoff between a peak power efficiency and a back-off power efficiency to increase a total power efficiency of the unequal array of power amplifiers and the array of antenna ports for transmitting signals.

9. The phased array communication system of claim 1, further comprising:

a plurality of phase shifters coupled to the array of transmission units; and

a clipping component, coupled to the plurality of phase shifters, configured to clip peak levels of the plurality of input signals.

10. A phased array device comprising:

an unequal array of power amplifiers comprising a first set of power amplifiers and a second set of power amplifiers different from the first set of power amplifiers; and

an array of antenna ports, coupled to the unequal array of power amplifiers, configured to transmit data signals having a phase and a gain that are respectively different from among the data signals, over the air at a predetermined angle, and reconstruct, over the air, an amplitude and a phase modulated signal comprising the phase and the gain from at least two of the transmit data signals over the air.

11. The phased array device of claim 10, wherein the data signals include WiGig signals or 5G signals transmitted or received in a millimeter wave band.

12. The phased array device of claim 10, wherein the first set of power amplifiers is configured to communicate the data signals at a first output power range and operate at a first saturation power level, and the second set of power amplifiers is configured to communicate the data signals at a second output power range and operate at a second saturation power level that are different from the first output power range and the first saturation power level.

13. The phased array device of claim 12, wherein the second set of power amplifiers of the unequal array of power amplifiers comprises a higher saturation power level than the first set of power amplifiers of the unequal array of power amplifiers.

14. The phased array device of claim 10, further comprising:

an adaptation component configured to selectively activate the first set of power amplifiers and the second set of power amplifiers to communicate the data signals based on a power efficiency target and a back-off power point.

15. The phased array device of claim 14, wherein the back-off power point is about 8 dB or greater from a peak saturation power of the first set of power amplifiers and the power efficiency target is approximately 50% or greater.

16. The phased array device of claim 11, further comprising:

a plurality of processing chains, coupled to the unequal array of power amplifiers and the array of antenna ports, comprising;

an I/Q RF digital-to-analog converter configured to convert the data signals from a radio frequency to a millimeter wave frequency; and

a set of switching units configured to connect at least one first power amplifier of the first set of power amplifiers and at least one second power amplifier of the second set of power amplifiers.

17. The phased array device of claim 10, wherein the first set of power amplifiers and the second set of power amplifiers comprises a ratio of 1 to N in number that is replicated throughout the unequal array of power amplifiers, wherein N is an integer of at least 2.

18. A method for a millimeter wave communication device comprising:

processing one or more data signals with an array of power amplifiers having unequal saturation power levels and unequal transmission powers based on a set of predetermined criteria; and

transmitting the one or more data signals, via an array of antenna ports coupled to the array of power amplifiers, at a predetermined angle that combines the one or more data signals over the air and reconstructs an amplitude and a phase modulated signal over the air.

19. The method of claim 18, wherein the set of predetermined criteria comprises at least one of a signal peak of the one or more data signals, an efficiency of the array of power amplifiers, or a back-off power level.

20. The method of claim 18, further comprising:

generating a tradeoff between a saturation power level and a back-off power level of at least one power amplifier of the array of power amplifiers to increase a transmission efficiency of the one or more data signals via the array of antenna ports coupled to the array of power amplifiers in a millimeter wave frequency band.

21. The method of claim 18, wherein the processing the one or more data signals with the array of power amplifiers comprises:

phase shifting the one or more data signals differently along signal chains coupled to the array of power amplifiers, respectively.

22. The method of claim 18, further comprising:

communicating the one or more data signals at a first output power range with a first set of power amplifiers of the array of power amplifiers at a back-off point from a first saturation power level; and

communicating the one or more data signals at a second output power range with a second set of power amplifiers of the array of power amplifiers at the back-off point from a second saturation power level.

23. The method of claim 22, wherein the second output power range is greater than the second output power range, and the first set of power amplifiers comprises a greater number of power amplifiers than the second set of power amplifiers in the array of power amplifiers.

24. The method of claim 18, further comprising:

selectively activating power amplifiers of the array of power amplifiers to increase an overall array power efficiency based on a back-off target level and a predetermined ratio of a first number of power amplifiers and a second number of power amplifiers of the array of power amplifiers, wherein the first number of power amplifiers comprise a lower peak power level than the second number of power amplifiers.