Some solutions to the problems described in previous sections are
- Channel Coding
- Interleaving
- Diversity
Although many of these do not entirely solve all problems on the radio transmission path, they do play an important part in maintaining call quality for as long as possible
Channel Coding
In digital transmission, the quality of the transmitted signal is often expressed in terms of how many of the received bits are incorrect.
This is called Bit Error Rate (BER).
BER defines the percentage of the total number of received bits which are incorrectly detected.
This percentage should be as low as possible. It is not possible to reduce the percentage to zero because the transmission path is constantly changing.
This means that there must be an allowance for a certain amount of errors and at the same time an ability to restore the information, or at least detect errors so the incorrect information bits are not interpreted as correct.
Channel coding is used to detect and correct errors in a received bit stream.
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