Most telecommunication signals contain hidden periodicities due to the periodic characteristics involved in the signals construction (carrier frequency, baud rate, coding scheme...). These periodicities are usually scrambled and hidden by the randomness of the transmitted message. However, by using a cyclostationary approach, this hidden periodicity can be recovered, making the identification of telecommunication signals possible. In this paper, it is shown how cyclostationary spatial processing techniques can limit the impact of the incoming radio frequency interference (RFI) for phased array radio telescopes. Cyclostationarity can be exploited for RFI detection purposes or for filtering purposes. These two RFI mitigation techniques are illustrated through simulations on data acquired with theWesterbork Telescope and the Low Frequency Array Radio telescope, LOFAR, in the Netherlands.