Radar proximity fuse and processing method of an echo radar signal for the acquisition of distance information between a target and a doppler radar

Radar proximity fuse (1) adapted for receiving a radar echo signal (s_rx) produced by the reflection on a target (T) of a transmitted radar signal (s_tx), the transmitted signal (s_tx) comprising a sequence of M pulses coded with a phase code (p_cd), the radar proximity fuse (1) comprising:

• a phase code generator (4) adapted to provide said phase code (p_cd);
• a radiofrequency analog receiving front end (15) for receiving the radar echo signal (s_rx), adapted to provide in output a baseband signal starting from the received radar echo signal (s_rx);
• an analog to digital converter (12) placed at the output of the analog receiving front end (15) adapted for sampling the baseband signal to obtain in output a sequence of digital samples (d_rx);
• a digital processing block (20) comprising a plurality of digital processing channels (C1, C2, . . . CN) configured to operate in parallel and each associated to a respective observation distance and each adapted for receiving in input said sequence of digital samples (d_rx);
• wherein each digital processing channel (C1, C2, . . . CN) comprises:
• a delay block (21) adapted for producing a replica of the phase code (p_cd) delayed with a respective time delay (d1, . . . , dN) corresponding to a respective observation distance between the fuse (1) and the target (T);
• a digital multiplier (22) adapted for multiplying the sequence of digital samples with digital samples of said delayed replica to produce in output a phase decoded sequence of digital samples;
• a digital information extraction block (23) adapted for processing the phase decoded sequence of digital samples to extract information correlated to the distance between the target (T) and the digital fuse (1).