- Tytuł:
- A new direct-sequence spread spectrum signal detection method for underwater acoustic communications in shallow-water channel
- Autorzy:
- Kochańska, Iwona
- Powiązania:
- https://bibliotekanauki.pl/articles/2146643.pdf
- Data publikacji:
- 2021
- Wydawca:
- Politechnika Poznańska. Instytut Mechaniki Stosowanej
- Tematy:
-
underwater acoustic communications
UAC
direct sequence spread spectrum
DSSS
akustyczna komunikacja podwodna
bezpośrednie modulowanie nośnej sekwencją kodową - Opis:
- Direct-Sequence Spread Spectrum (DSSS) is one of the modulation and coding techniques used in Underwater Acoustic Communication (UAC) systems for reliable data transmision even at low signal levels. However, in a shallow water channel, there is a strong multipath propagation which causes a phase fluctuation of the received signal, affecting the performance of the spread-spectrum system. The article presents a differential method for DSSS signal detection. It is based on the calculation of the correlation coefficient of adjacent segments of signal at the output of filter matched to the spreading sequence used in the transmitter. A positive value of the correlation coefficient means that a given modulation symbol carries the same information bit as the previous one; a negative value means that the opposite bit has been transmitted. The reliability of the proposed method has been compared to classical method of DSSS signal detection, which consists in detecting the information directly from the signal at the output of the matched filter. Simulation and measurement tests of underwater acoustic communications in strong multipath propagation conditions have shown that the proposed method allows obtaining lower values of the DSSS transmission Bit Error Rate (BER) than the classical detection technique while maintaining the same data transmission rate.
- Źródło:
-
Vibrations in Physical Systems; 2021, 32, 1; art. no. 2021106
0860-6897 - Pojawia się w:
- Vibrations in Physical Systems
- Dostawca treści:
- Biblioteka Nauki
Artykuł