Caption: Figure 5: Bit energy enhancement percentages of SRMR-DCSK compared to DCSK for the
spreading factor [beta] = 100.
Our analysis revealed that, at half bit energy, the proposed scheme outperforms DCSK and CDSK at average of 1.25 db while DCOOK shows superior performance compared to COOK at wide range of
spreading factor. Additionally, DCOOK offers double data rate compared to DCSK.
The number of channels used for transmission is the same as the
spreading factor, which is the number of digits in the user code, so the entire pattern of plus and minus ones arrives at the destination for each transmission, in unison.
The relationship between symbol EVM and EVM at the chip level depends on the
spreading factor. At low
spreading factors (high data rates), chip modulation errors have a significant effect on symbol EVM, but at high
spreading factors, chip modulation errors have very little effect on symbol EVM.
The actual number of bits depends on the data rate and hence the
spreading factor. The 2n bits are mapped onto n QPSK complex symbols.