**Commenced**in January 2007

**Frequency:**Monthly

**Edition:**International

**Paper Count:**32297

##### Efficient Alias-free Level Crossing Sampling

**Authors:**
Negar Riazifar,
Nigel G. Stocks

**Abstract:**

This paper proposes strategies in level crossing (LC) sampling and reconstruction that provide alias-free high-fidelity signal reconstruction for speech signals without exponentially increasing sample number with increasing bit-depth. We introduce methods in LC sampling that reduce the sampling rate close to the Nyquist frequency even for large bit-depth. The results indicate that larger variation in the sampling intervals leads to alias-free sampling scheme; this is achieved by either reducing the bit-depth or adding a jitter to the system for high bit-depths. In conjunction with windowing, the signal is reconstructed from the LC samples using an efficient Toeplitz reconstruction algorithm.

**Keywords:**
Alias-free,
level crossing sampling,
spectrum,
trigonometric polynomial.

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