Coding (which is a controlled redundancy) and interleaving across sub-carriers protects OFDM signals from a narrow band interferer (CW) that could destroy one subcarrrier. It provides a kind of frequency diversity
Suppose we have an AWGN channel , a coded OFDM signal with a certain modulation and coding scheme at a low coding rate and a certain corresponding sensitivity.
Suppose now that this signal is hit with a strong inband CW destroying one subcarrier, would the protection provided by coding and interleaving allow reception of this signal at the same sensitivity level when it was exposed to AWGN only?
Best Answer
A strong inband carrier may be strong enough to overload the frontend Low Noise Amplifier transistor, and prevent ANY of the OFDM passing thru.
On the other hand, dropping the desired signal and the inband carrier/jammer by 20/30//50/80 dB should just impair that one channel of the large number used by the OFDM.
If there is enough interleaving, despite the low-coding gain (such as Viterbi 7/8, not 1/2), then you may succeed. If you expect big problems, you might employ handshaking at various times, and upon TX/RX agreement switch from 7/8 to 1/2 when interference requires that for a viable signal.