Phased-array transceiver for millimeter-wave frequencies

• US 8,618,983 B2
• Filed: 03/30/2010
• Issued: 12/31/2013
• Est. Priority Date: 09/13/2009
• Status: Active Grant

• Current Assignee: International Business Machines Corporation, MediaTek, Inc.
• Original Assignee: International Business Machines Corporation, MediaTek, Inc.
• Inventors: Chen, Ping-Yu, Floyd, Brian A., Lai, Jie-Wei, Natarajan, Arun S., Nicolson, Sean T., Reynolds, Scott K., Tsai, Ming-Dai, Valdes-Garcia, Alberto, Zhan, Jing-Hong C.
• Primary Examiner(s): GALT, CASSI J
• Application Number:
  US12/750,242
• Publication Number:
  US 20110063169A1
• Time in Patent Office: 1,372 Days
• Field of Search: 342/368, 342/371, 342/372, 342/373, 342/374, 342/375, 342/377
• US Class Current: 342/368
• CPC Class Codes: H01Q 3/267 Phased-array testing or checking devices
• CPC Class Codes: H01Q 3/2694 using also variable phase-shifters H01Q3/2688 takes precedence

Abstract

A phased-array transmitter and receiver that may be effectively implemented on a silicon substrate. The transmitter distributes to front-ends, and the receiver combines signals from front-ends, using a power distribution/combination tree that employs both passive and active elements. By monitoring the power inputs and outputs, a digital control is able to rapidly provide phase and gain correction information to the front-ends. Such a transmitter/receiver includes a plurality of radio frequency (RF) front-ends and a power splitting/combining network that includes active and passive components configured to distribute signals to/from the front-ends.

Claims

1. A phased-array transmitter having beam-steering ability, comprising:

a plurality of radio frequency (RF) front-ends, each configured to transmit a signal with a given phase relative to the others such that the amplitude of the transmitted signal is highest in a given direction, each of the RF front-ends comprising;

a phase shifter configured to delay the signal in accordance with the given direction; and

a variable amplifier configured to adjust the gain of the signal; and

a power distribution network configured to accept an RF signal from an up-conversion element and to selectively pass the RF signal to one or more of the RF front-ends such that unselected RF front-ends do not receive the RF signal, wherein the power distribution network includes active components and passive combiners that include a cross-coupled transmission line and a decoupling resistive network.

2. The transmitter of claim 1, wherein the RF front-ends further comprise a digital beam table configured to adjust the phase shifter'"'"'s phase delay and the variable amplifier'"'"'s gain.

3. The transmitter of claim 2, wherein the RF front-ends further comprise a power sensor configured to measure each RF front-end'"'"'s power output.

4. The transmitter of claim 3, further comprising a digital control configured to determine an optimal phase delay and gain for each RF front end and to provide that information to the beam table of each RF front-end.

5. The transmitter of claim 4, wherein the digital control is further configured to account for manufacturing and environmental variations in its determination of optimal phase delay and gain.

6. The transmitter of claim 4, further comprising a multiplexer configured to accept the power measurements from each RF front-end'"'"'s power sensor and further configured to output any individual power signal or an aggregation of all power outputs.

7. The transmitter of claim 1, wherein the phase shifter of each RF front end is a passive phase shifter configured to provide a continuous 180 degree range of phase shift and the variable amplifier of each RF front end is a differential phase-inverting amplifier configured to provide an additional 180 degrees of discrete phase shift and variable gain amplification.

8. The transmitter of claim 1, wherein the passive combiners in the power distribution network comprise one or more modified Gysel splitters, configured to passively split a signal and the active components in the power distribution network comprise one or more active distribution amplifiers, configured to amplify and split a signal.

9. The transmitter of claim 1, further comprising a buffer configured to provide loopback information to an associated receiver.

10. The transmitter of claim 1, wherein the phased-array transmitter is formed on an integrated circuit chip.

11. A method for beam-steering in a phased-array transmitter implemented on a silicon substrate, comprising the steps of:

distributing a signal to a plurality of transmitter front-ends formed on a silicon substrate, comprising selectively passing the signal to the plurality of transmitter front-ends, such that unselected front-ends do not receive the signal;

phase shifting the signal at each transmitter front-end such that the transmitter outputs interfere to produce a directed beam;

measuring the combined power output of a plurality of the transmitter front-ends; and

adjusting an amplification gain of an amplifier in each of the front-ends based on the measured power output to compensate for deviations from an optimal power output.

12. The method of claim 11, further comprising the step of monitoring environmental conditions, wherein the step of adjusting further adjusts the amplification gain of the transmitter front-ends based on said environmental conditions.

13. The method of claim 11, wherein said step of phase shifting directs the beam to avoid obstacles in the line of sight.