公开(公告)号：US11005691B2

公开(公告)日：2021-05-11

申请号：US16759238

申请日：2018-10-22

Applicant: AIRBUS DEFENCE AND SPACE SAS

Inventor： Benjamin Gadat ,  Mehdi Anteur

IPC: H04L27/00 ,  G01R23/02 ,  H04B7/185

Abstract: A method (50) for estimating a frequency shift and a frequency drift affecting a useful signal including a code word formed by a channel encoder, including an analysis phase (51) including: for two analysis frequency drifts: a compensation (52) of the analysis frequency drift on the useful signal, an estimation (53) of the frequency shift on each useful signal obtained after compensation, a selection (54) of frequency hypotheses,
and an estimation phase (55) including: for each frequency hypothesis: a frequency recalibration (56) of the useful signal depending on the frequency hypothesis, in order to obtain sample sequences, an evaluation (57) of the probability of each sample sequence to be a code word of said channel encoder, an estimation (58) of the frequency shift and of the frequency drift depending on the most probable frequency hypothesis.

公开(公告)号：US10921355B2

公开(公告)日：2021-02-16

申请号：US15549199

申请日：2016-02-12

Applicant: AIRBUS DEFENCE AND SPACE SAS

Inventor： Mathieu Picard ,  Mehdi Anteur

IPC: G01R23/167 ,  G01R23/18

Abstract: A method for detecting a plurality of useful signals in a total signal. The useful signals correspond to radiofrequency signals emitted by different terminals in a multiplexing frequency band. A plurality of spectrograms calculated that have a compensated linear frequency drift and are respectively associated with different linear frequency drift values. For each analysis frequency and each spectrogram, time envelope filtering of the values is performed at the different times for analyzing the spectrogram at the analysis frequency using a filter representing a reference time envelope of the useful signals. A useful signal is detected at an analysis time and at an analysis frequency in response to a verification of a predefined detection criterion by the value from a spectrogram resulting from filtering at the analysis time and at the analysis frequency.