Cyclostationarity-based spatial event detection using signal subspace of array antenna

This paper proposes an alternative method for an indoor event detection scheme that realizes immunity against co-channel interference by exploiting the cyclostationarity of the desired signal. The previous indoor event detection scheme [3] can detect events such as home or office intrusion by using signal subspace spanned by an eigenvector obtained by an array antenna, and delivers superior performance compared with conventional event detection methods based on received signal strengths (RSS). Similar to the conventional methods, however, the signal subspace-based sometimes suffers from interference in the same frequency band. The method proposed in this paper exploits the cyclostationarity of communication signals to distinguish the desired signal from the interference that impinges on an array antenna, and suppresses noise and interfering signals without major hardware design changes. The proposed algorithm is computationally simple and offers good detection performance. The effectiveness of the proposed method is verified through numerical examples. Finally, an evaluation equipment of the event detection system is introduced to realize the real-time event detection.