What is zero forcing equalizer?

Zero forcing equalizer is a type of linear equalizer used in digital communication systems to suppress the effects of inter-symbol interference (ISI) caused by the channel. It is also known as the matrix inverse equalizer. The zero forcing equalizer works by forcing the output of the equalizer to be equal to the input, thus removing any interference caused by the channel.

The zero forcing equalizer uses a matrix inverse to estimate the channel impulse response and then removes the effect of the channel from the received signal. The equalizer is designed based on the transmission channel's characteristics, which should be known beforehand. The zero forcing equalizer is simple to implement and is relatively computationally efficient.

The zero forcing equalizer is best suited for transmission channels with linear, time-invariant (LTI) characteristics. However, it is known to amplify noise, which can lead to bit errors. Therefore, it is not recommended for use in noisy channels. Other types of equalizers, such as the maximum likelihood sequence estimator (MLSE) equalizer or the decision feedback equalizer (DFE), are more appropriate for noisy channels.