Single‐channel Signal Enhancement in the Time Domain

This chapter focuses on the study of the signal enhancement problem in the time domain with a single sensor. It shows how to fully exploit the temporal information in order to reduce the level of the additive noise from the observations. The chapter discusses two important approaches: the conventional one, which is based on the fundamental Wiener filtering, and the spectral approach, which is based on the spectrum of the desired and noise signals. It also gives examples to show the benefits of both approaches. One of the most fundamental measures in all aspects of signal enhancement is the signal‐to‐noise ratio (SNR). There are two approaches to find the gains from the fullmode output SNR in order to perform noise reduction. The first one considers the largest spectral mode input SNRs. The second method considers the smallest spectral mode input SNRs.