Fractionally Spaced Adaptive Equalizer: A Review

Due to non-linear channel behaviour, the bit error rate at the receiver side increases and receiver is not able to recognize the signal levels. Equalizer play an important role is such situations and is designed to have an impulse response which is reciprocal to the response of the channel, hence resulting in an overall linear response. As channel response is not static in nature, so equalizer should have adaptation property. Different adaptive equalizers have been quoted in literature, but due to their performance superiority and the availability of variants stochastic gradient algorithm that mitigate coefficient drift during decision-directed operation, fractionally spaced adaptive equalizers are gaining vital importance these days. This paper presents a detailed insight into the structure and superiority of fractionally spaced adaptive equalizers.