Wireless communication with interference mitigation

Patent metadata

Field	Value
Publication number	US-2016112111-A1
Application number	US-201514984553-A
Country	US
Kind code	A1
Filing date	Dec 30, 2015
Priority date	Sep 12, 2014
Publication date	Apr 21, 2016
Grant date	—

Abstract

In one implementation, a wireless communication terminal includes a primary antenna array and a first controller configured to steer a main beam of the primary antenna array in a desired direction. The wireless communication terminal also includes an auxiliary antenna array and a second controller configured to control complex weights to be applied by at least some antenna elements of the auxiliary antenna array to corresponding variants of a second signal received by the at least some auxiliary antenna elements. Furthermore, the wireless communication terminal includes at least one signal combiner configured to combine variants of the second signal received from auxiliary antenna elements into an interfering signal that models interference from a co-located wireless communication terminal and subtract the interfering signal from variants of the first signal received from antenna elements of the principal antenna array to produce an interference mitigated signal.

First claim

What is claimed is:

1 . A wireless communication terminal comprising:
a primary antenna array including a first number of primary antenna elements, individual ones of the primary antenna elements being configured to receive variants of a first signal; a first controller configured to steer a main beam of the primary antenna array in a desired direction; an auxiliary antenna array including a second number of auxiliary antenna elements, individual ones of the auxiliary antenna elements being configured to receive variants of a second signal; a second controller configured to control, based on the desired direction of the main beam of the primary antenna array, complex weights to be applied by at least some of the auxiliary antenna elements to the corresponding variants of the second signal received by the at least some auxiliary antenna elements; and at least one signal combiner configured to:
combine variants of the second signal received from auxiliary antenna elements into an interfering signal, the interfering signal to model interference from a co-located wireless communication terminal, and
subtract the interfering signal from variants of the first signal received from principal antenna elements to produce an interference mitigated signal.

2 . The wireless communication terminal of claim 1 , further comprising a power receiver to measure power of the interference mitigated signal, wherein the second controller is configured to control the complex weights to be applied to reduce the power of the interference mitigated signal measured by the power receiver.

3 . The wireless communication terminal of claim 1 , further comprising:
an oscillator configured to convert the interference mitigated signal to an intermediate frequency, wherein the interfering signal is subtracted from the variants of the first signal before the interference mitigated signal is converted to the intermediate frequency.

4 . The wireless communication terminal of claim 1 , wherein:
the first controller is configured to steer the main beam of the primary antenna array in a plurality of predetermined directions; and the second controller is further configured to control the complex weights to be applied by the at least some of the auxiliary antenna elements for each predetermined direction in which the first controller is configured to steer the main beam of the primary antenna array.

5 . The wireless communication terminal of claim 1 , wherein the at least one signal combiner includes:
a first signal combiner configured to combine the variants of the second signal received from the auxiliary antenna elements into the interfering signal; and a second signal combiner that is different from the first signal combiner configured to subtract the interfering signal from the variants of the first signal received from the principal antenna elements to produce the interference mitigated signal.

6 . The wireless communication terminal of claim 1 , wherein the at least one signal combiner includes:
a first signal combiner to combine variants of the first signal received from principal antenna elements into a main signal; a second signal combiner that is different from the first signal combiner configured to combine the variants of the second signal received from the auxiliary antenna elements into the interfering signal; and a third signal combiner that is different from the first and second signal combiners configured to subtract the interfering signal from the main signal to produce the interference mitigated signal.

7 . The wireless communication terminal of claim 1 , wherein the at least one signal combiner is configured to:
combine variants of the second signal received from all of the auxiliary antenna elements into the interfering signal; and subtract the interfering signal from variants of the first signal received from all of the principal antenna elements to produce an interference mitigated signal.

8 . The wireless communication terminal of claim 2 , wherein:
the first controller is configured to:
steer the main beam of the primary antenna in a new desired direction, and
communicate an indication of the new desired direction to the second controller; and
the second controller is configured to:
receive the indication of the new desired direction, and
change the complex weights to be applied by at least some of the auxiliary antenna elements to the corresponding variants of the second signal received by the at least some auxiliary antenna elements based on the new desired direction.

9 . The wireless communication terminal of claim 1 , wherein:
each of at least some of the primary antenna elements is configured to apply a complex weight to the variant of the first signal received by the primary antenna element; and the first controller is configured to steer the main beam of the primary antenna array in a desired direction by controlling complex weights applied by the at least some primary antenna elements to the variants of the first signal received by the at least some primary antenna elements.

10 . The wireless communication terminal of claim 9 , wherein each of at least some of the primary antenna elements include:
a power amplifier to amplify a variant of a third signal to be transmitted by the primary antenna element; and a low noise amplifier to amplify the variant of the first signal received by the primary antenna element.

11 . The wireless communication terminal of claim 1 , wherein the first number of primary antenna elements is greater than the second number of auxiliary antenna elements.

12 . The wireless communication terminal of claim 1 , wherein the second controller is configured to control, based on the desired direction of the main beam of the primary antenna array, a complex weight to be applied by each auxiliary antenna element to the corresponding variant of the second signal received by the auxiliary antenna element.

13 . The wireless communication terminal of claim 1 , wherein:
a desired signal is transmitted by two or more satellites orbiting the earth; and the first controller is configured to:
steer the main beam of the primary antenna array in a desired direction to receive the desired signal from a first one of the satellites, and
change the direction of the main beam of the primary antenna array to a new desired direction to receive the desired signal from a second one of the satellites based on a determination that the main beam of the primary antenna array will be subjected to interference from a co-located satellite terminal when steered in the desired direction to receive the desired signal from the first satellite.

14 . A method for processing a desired signal by a wireless communication terminal, comprising:
receiving a main signal with a primary antenna array, the main signal including noise from a proximally located wireless communication terminal received in one or more side lobes of the primary antenna array; receiving variants of a secondary signal with corresponding antenna elements of an auxiliary antenna array; setting complex weights to be applied by individual antenna elements of the auxiliary antenna array to the corresponding variants of the secondary signal received by the individual antenna elements based on a direction of a main beam of the primary antenna array; applying the complex weights to the corresponding variants of the secondary signal received by the individual antenna elements to shift the variants of the secondary signal received by the individual antenna elements; combining the shifted variants of the secondary signal into an

Assignees

• Iridium Satellite Llc

Inventors

• Bull Jeffrey Francis

Classifications

• H04W52/52

  using AGC [Automatic Gain Control] circuits or amplifiers · CPC title

• H04W52/243 Primary

  taking into account interferences · CPC title

• H04B1/44

  Transmit/receive switching · CPC title

• H04B7/18519

  Operations control, administration or maintenance · CPC title

• H04W16/28

  using beam steering · CPC title