This letter proposes a frequency domain equalization (FDE) scheme with a threshold in molecular communication (MC). The responses of a MC channel are tendency to have low pass characteristics and intersymbol interference limits the data rates of MC. However, because of the characteristics of the MC channel, equalization coefficients for high frequency components may increase. Therefore, noise enhancement occurs and it deteriorates communication performance. As large channel responses concentrate at around a zero-frequency component, in the proposed equalization scheme, the high frequency component of the received signal is eliminated if the equalization coefficient exceeds a threshold in the proposed scheme. Numerical results obtained through computer simulation show that the threshold improves the communication performance with the proposed FDE. It is also shown that the trade-off between the noise enhancement and the pulse waveform effects on the performance.

No abstract

No abstract

This letter proposes approximated zero forcing precoding with a threshold in molecular communication (MC). Frequency domain precoding for channel equalization is investigated. Owing to the restriction of a transmitter in MC the main part of an equalized waveform is extracted and a corresponding rectangular waveform is transmitted. In the proposed equalization scheme, the frequency component of the transmit signal is suppressed if a threshold exceeds the channel coefficient in the proposed scheme. Numerical results obtained through computer simulation show that approximation by a single rectangular waveform achieves almost the same performance as that with rectangular approximation that suppresses inter-symbol interference with the proposed precoding technique.