Calibration method for smart antenna arrays

(54) CALIBRATION METHOD FOR SMART ANTENNA ARRAYS

(75) Inventor: Kurt Weese, Ditzingen (DE)

Correspondence Address:

SUGHRUE MION, PLLC

2100 PENNSYLVANIA AVENUE, N.W.

SUITE 800

WASHINGTON, DC 20037 (US) (73) Assignee: ALCATEL

(21) Appl. No.: 11/517,308

(22) Filed: Sep. 8, 2006

(30) Foreign Application Priority Data

Sep. 28, 2005 (EP) 05 292 023.8

Publication Classification

(51) Int. CI.

G01S 7/40 (2006.01)

(52) U.S. CI 342/174

The invention relates to a method of calibrating the reception path and the transmit path of an antenna array which comprises at least three antennas and which is connected to a digital signal processor. For calibrating the reception path a signal of known amplitude and known phase is transmitted by a single antenna, whereby this signal is received by the other n-1 antennas, whereby a phase difference and an amplitude difference between each of the n-1 transmitted signals is evaluated. The last two steps are repeated with a new transmit antenna until every antenna has been used as a transmit antenna. In the last step the phase differences and their associated amplitude differences are set to the factorysaid values. For calibrating the transmits path of an antenna array 1 comprising at least three antennas and being connected to a digital signal processor, a method comprises the step transmitting a signal of a known amplitude and known phase by n-1 antennas and receiving these signal by the n antenna, evaluating a phase difference and an amplitude difference between each of the n-1 transmitted signals, repeating the last two steps with a new receiving antenna until every antenna has been used as a receiving antenna, compensating the phase differences and their associated amplitude differences to the factory-set values.