1. A QR decomposition detection device supporting interference whitening, the device comprising: a whitening unit to perform whitening of interference existing in a reception symbol vector using a whitening matrix calculated based on an interference channel matrix, and to generate a manufactured vector; a QR decomposition unit to perform QR decomposition based on the whitening matrix and a target channel matrix, which is distinguished from the interference channel matrix; and a detector to detect a transmission symbol vector corresponding to the reception symbol vector based on the manufactured vector and a result of the QR decomposition.