Communication system node comprising a transformation matrix

Patent metadata

Field	Value
Publication number	US-9728850-B2
Application number	US-201013580896-A
Country	US
Kind code	B2
Filing date	Feb 25, 2010
Priority date	Feb 25, 2010
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

The present invention relates to a node ( 1 ) in a wireless communication system, the node ( 1 ) comprising at least one antenna ( 2 ) which is arranged to cover a first sector ( 3 ) in a first direction ( 4 ) and comprises a number (A) of antenna ports ( 5, 6, 7, 8 ), which number (A) is at least four. The antenna ports ( 5, 6, 7, 8 ) are connected to a transformation matrix ( 9 ) which is arranged for transforming the antenna ports ( 5, 6, 7, 8 ) to at least a first set (S 1 ) of virtual antenna ports ( 10, 11 ) and a second set (S 2 ) of virtual antenna ports ( 12, 13 ), each set (S 1 , S 2 ) comprising a number (B) of virtual antenna ports ( 10, 11; 12, 13 ). The present invention also relates to a corresponding method.

First claim

The invention claimed is:

1. A node in a wireless communication system, the node comprising:
at least one antenna configured to cover a first sector in a first direction and comprising a number N of antenna ports, wherein the number N of antenna ports is at least four and is even; and
a circuit connected to the antenna ports and configured to transform the antenna ports with a transformation matrix, wherein the transformation matrix is configured to apply a linear transformation to the N antenna ports to transform them to at least a first set (S 1 ) of N/2 virtual antenna ports and a second set (S 2 ) of N/2 virtual antenna ports, wherein N/2 is not less than two, where the sets (S 1 , S 2 ) of virtual antenna ports correspond to virtual antennas which are configured to cover at least a second sector and a third sector in a corresponding second direction and third direction, respectively, wherein the first sector is covered by the N antenna ports, and wherein the transformation matrix is configured to cause the second sector (B) to be covered by a beam formed from the N/2 virtual antenna ports of the first set (S 1 ) and to cause the third sector (C) to be covered by a beam formed from the N/2 virtual antenna ports of the second set (S 2 ), wherein the transformation matrix is configured to control a beamwidth and a beam direction of a beam formed by the virtual antennas of the second sector or of the third sector,
wherein the transformation matrix is formed by stacking array weight vectors as columns according to
W=[w B,1 w B,2 w C,1 w C,2 ],

where each w is a complex weight vector and vector w k,n creates beam number n in sector k, and where denotes the number of sectors and N denotes the number of beams per sector,
wherein

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Assignees

• Athley Fredrik
• Petersson Sven
• ERICSSON TELEFON AB L M (publ)

Inventors

• Athley Fredrik
• Petersson Sven

Classifications

• H01Q25/00

  Antennas or antenna systems providing at least two radiating patterns (arrangements for changing or varying the orientation or the shape of the directional pattern H01Q3/00) · CPC title

• H01Q3/40 Primary

  with phasing matrix · CPC title

• H01Q3/30

  varying the {relative} phase {between the radiating elements of an array (H01Q3/2605, H01Q3/2658, H01Q3/2682, H01Q3/44 take precedence)} · CPC title

• H01Q1/246 Primary

  specially adapted for base stations · CPC title