1. A method for acquiring a radionavigation signal carrying a spreading code with a period that is at least 10 times longer than the correlation time, comprising: sampling the baseband radionavigation signal on a delay line, and correlating the radionavigation signal on the delay line with a local spreading code replica so as to identify a time delay between the spreading code of the radionavigation signal and the local spreading code replica in a temporal alignment search space; wherein, in order to correlate the baseband radionavigation signal with the local spreading code replica, a plurality of spreading code sequence(s) are generated, said spreading code sequence(s) being of the same duration, equal to the duration of the radionavigation signal sampled on the delay line, and associated with the consecutive time ranges in the temporal alignment search space, each of the spreading code sequence(s) is correlated with the radionavigation signal sampled in a respective correlation operation, said correlation operations being executed in parallel for the different spreading code sequences.