Spectrum sensing is a key technology in the cognitive radio network, in order to protect the primary user, the sensing algorithms must have a high detection efficiency and detection accuracy. This paper mainly focuses on the spectrum sensing in MIMO environment. Considering that the non-circular signal is usually used in the communication system, a novel spectrum sensing method is proposed for non-circular signals based on the Locally Most Powerful Invariant Test(LMPIT). The theoretical threshold is derived...