Digital Signal Processing Reference
In-Depth Information
A radio communications in a cellular phone is a degraded channel.
Accordingly, the proposed code's performance in CDMA, which is the
communication system of a cellular phone of the current generation, was
evaluated using simulator. The tool used for the simulation was a MATLAB,
and the CDMA environment was built using the attached IS-95 library in the
MATLAB. The proposed code has a disadvantage in radio communications
because it decodes by hard decision. In analog channel, introducing a soft-
decision code can raise a correction ability. When we used the product code,
an outer code was the proposed code, and an inner code was the
convolutional code. Simulation conditions are summarized in Table 7-2.
Figure 7-5 indicates that a fluttering error occurred in the characteristic curve
of the Turbo code, and the Turbo code did not reduce the error to the
Alternatively, the proposed code made a
reduction in error.
Figure 7-4.
Results of comparing reed-solomon code with the proposed code.
Figure 7-6 shows the improvement in the decoded bit error rate versus
Eb/No for AWGN environment. At the decoded BER of the required
input BER of the proposed code is 0.020 and 0.026 for 4Dm6 and 4Dm5,
respectively. In contrast, the coding gain of the 8-PSK TCM is given by the
minimum Euclidean distance of
against the
