The rest of this paper is organized as follows: In Section 2, a description of the SISO-SRMR-DCSK transmitter scheme and demodulation structure is given, and the traditional DCSK system is described briefly.
In the DCSK system, half of the frame time is used to transmit the reference signal that does not carry any useful information; thus, the data transmission rate is reduced.
This is different from the traditional DCSK. For the SISO-SRMR-DCSK system, the length of the reference signal changes from [beta] to R, where R is 1/P of the data signal length.
The SISO-SRMR-DCSK system compared to the DCSK system to improve the data transmission rate can be expressed below:
The DCSK system is simple and largely considered; however, it suffers from several drawbacks, that is, low data rate, high energy consumption, using complex wideband delay, and so on.
Particularly, the performance of the DCSK system under the single-tone jamming (STJ) environment is studied.
For a comparison purpose, the BERs of the DCSK and the I-DCSK systems are also plotted.
(i) Notable improvement in BER (up to 1.5 dB) compared to standard DCSK and CDSK schemes using only half of their bit energy.
Standard chaos based systems including DCSK, CDSK, and COOK are described in Section 2.
DCSK. For each bit of information, the DCSK transmitter outputs a chaotic sequence xi at time instant i.
Modem, Loss rate Topology size standard in [%] and Data rate Small- Medium- Large- modulation in [kbps] size size size Yitran, Loss rate 0 0 71.3 DCSK
with Data rate 3.27 2.71 2.24 ROBO C2000,PRI Loss rate 0 100 100 MED8PSK Data rate 9.14 0 0 C2000, G3, Loss rate 0 0 0 ROBO Data rate 2.36 2.18 1.76 SGCM-P40, Loss rate 0 0 0 G3, ROBO Data rate 5.3 5.3 5.3 SGCM-P40, Loss rate 0 2.1 100 G3, D8PSK Data rate 43.39 43.39 0 TABLE V.
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