Phase or amplitude compensation for beam-former

Patent metadata

Field	Value
Publication number	US-10917162-B2
Application number	US-201415103801-A
Country	US
Kind code	B2
Filing date	Dec 12, 2014
Priority date	Dec 12, 2013
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

Phase or amplitude compensation for beam-former Apparatus for an antenna with a plurality of antenna elements, the antenna providing a radiation pattern including one or more beams and the apparatus comprising: a digital beam-former for digitally weighting component signals corresponding to the one or more beams with respective beam-forming weights to provide each component signals of a beam with a phase relationship and amplitude relationship to other component signals of the same beam; and a processing arrangement for processing signal for the beam-former or for processing signals received from the beam-former; the apparatus further comprising compensation means for compensating for at least one out of phase and amplitude distortions between component signals associated with the same frequency channel and related to the same beam arising in the processing arrangement.

First claim

The invention claimed is:

1. An apparatus for an antenna with a plurality of antenna elements, the antenna providing a radiation pattern including one or more beams and the apparatus comprising:
a digital beam-former for digitally weighting component signals corresponding to the one or more beams with respective beam-forming weights to provide each component signal of a beam with a phase relationship and amplitude relationship to other component signals of the same beam; and
a processing arrangement comprising:
a plurality of frequency converters, each frequency converter of the plurality of frequency converters being associated with a separate antenna element of the plurality of antenna elements and being configured to frequency convert an antenna element signal associated with the separate antenna element to an intermediate frequency band, wherein each frequency converter is configured to frequency convert its antenna element signal to a different frequency band such that the frequency-converted antenna element signals are stacked in frequency with respect to each other, an analog-to-digital converter for converting a composite signal comprising a plurality of said stacked antenna element signals from analog to digital form and a demultiplexer for demultiplexing the digital signal into component signals present in said antenna element signals for providing to the digital beam-former, the demultiplexer comprising a poly-phase filter, wherein the plurality of stacked antenna element signals comprise a plurality of signals corresponding to the plurality of antenna elements; or
a multiplexer for multiplexing beam-formed component signals, for forming a number of antenna element signals, from the digital beam-former into a composite signal comprising said number of antenna element signals stacked with respect to each other in frequency and a digital-to-analog converter for converting the composite signal from digital to analog form, and a plurality of frequency converters, each frequency converter of the plurality of frequency converters being associated with a separate antenna element of the plurality of antenna elements and being configured to frequency convert an antenna element signal from one of said frequency bands to a frequency at which it will be transmitted by a respective antenna element; the multiplexer comprising a synthesis poly-phase filter, wherein the plurality of stacked antenna element signals comprise a plurality of signals corresponding to the plurality of antenna elements;
the apparatus further comprising compensation means for compensating for at least one out of phase and amplitude distortions between component signals associated with the same frequency channel and related to the same beam arising in the processing arrangement, wherein for a given component signal, the compensation means are configured to determine a plurality of compensation complex weights each corresponding to a relative distortion introduced by a component within the processing arrangement, and multiply the plurality of compensation complex weights to determine a final compensation weight with which to weight the component signal, and the component within the processing arrangement comprises one of the analog-to-digital converter, the poly-phase filter, the synthesis poly-phase filter, or the digital-to-analog converter.

2. The apparatus according to claim 1 , wherein the compensation means are provided in said digital beam-former.

3. The apparatus according to claim 2 , wherein the digital beam-former comprising adjusters for adjusting at least one out of phase and amplitude of the component signals, each adjuster being configured to apply a weight to a respective component signal corresponding to a beam-forming weight and a compensation weight, the compensation weight being selected to compensate for at least one out of a phase and amplitude distortion arising in the processing arrangement relative to other component signals for the same beam.

4. The apparatus according to claim 1 , wherein the compensation means are provided separately from said beam-former in said processing arrangement, the compensation means comprising adjusters for adjusting at least one out of phase and amplitude of the component signals, each adjuster being configured to apply a compensation weight to a respective component signal selected to compensate for at least one out of a phase and amplitude distortion arising in the processing arrangement relative to other component signals for the same beam.

5. The apparatus according to claim 3 , wherein the compensation weight is a complex number and wherein said adjusters are configured to adjust their respective component signals by carrying out a complex multiplication.

6. The apparatus according to claim 1 , wherein the apparatus comprises a receive system and wherein said processing arrangement comprises:
a plurality of groups of frequency converters, one of said groups comprising said plurality of frequency converters and each frequency converter in each group is configured to frequency convert its antenna element signal to a different frequency band;
a plurality of combiners, each combiner being associated with a group of frequency converters and being configured to combine the antenna element signals in said different frequency bands to a composite signal;
a plurality of analog to digital converters, each analog to digital converter being configured to convert a different composite signal into digital form; and
a plurality of demultiplexers for demultiplexing the converted signals.

7. The apparatus according to claim 6 , wherein the compensation means being configured to compensate for a phase distortion in the demultiplexer and further being configured to apply a compensation determined based on intermediate frequency band from which component signal is down-converted in the demultiplexer.

8. The apparatus according to claim 6 , wherein the compensation means is configured to compensate for a phase distortion generated in the analog to digital converter and the compensation means further being configured to apply a compensation determined based on the timing of a clock edge of a sampling clock of the analog to digital converter relative to the timing of clock edges of sampling clocks of other analog to digital converters of the plurality of analog to digital converters.

9. The apparatus according to claim 1 , wherein the apparatus comprise a transmit module and wherein the processing arrangement comprises:
a plurality of multiplexers for multiplexing beam-formed component signals, each multiplexer being configured to multiplex beam-formed component signals for forming a number of antenna element signal into a composite signal comprising said number of antenna element signals stacked with respect to each other in different intermediate frequency bands;
a plurality of digital to analog converters, each digital to analog converter being configured to convert a different composite signal into analog form; and
a plurality of splitters for splitting each digital to analog converted signal into the antenna element signals present in said digital to analog converted signal in the different intermediate frequency bands.

10. The apparatus according to claim 9 , wherein the compensation means being configured to compensate for a phase distortion by the multiplexer and further being configured to apply a compensation determined based on intermediate frequency band to which component signal is up-converted in the multiplexer.

11. The apparatus according to claim 9 , wherein the compensation means is configured to compensate for a phase distortion generated in the digital to analog converter and

Assignees

• Airbus Defence & Space Ltd

Inventors

• Smart Robert
• Leong Chiok

Classifications

• H04B7/0617

  for beam forming · CPC title

• H01Q3/26

  varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture ({H01Q3/12,} H01Q3/22, H01Q3/24 take precedence) · CPC title

• H04B7/0842

  Weighted combining · CPC title

• H04B7/18515 Primary

  Transmission equipment in satellites or space-based relays · CPC title

• H04B7/2041

  Spot beam multiple access · CPC title