including the sign bit and p is the word length of the fractional part. As indicated in Table I, φ and ψ have the same dynamic range, thus φ and ψ are quantized to (16,15) for fair comparison. In Fig. 3(a), we observe that for the conventional basis functions φ, it’s difficult to quantize the elements with a reasonable finite word length, especially when x ≤ 0.4. Fig. 3(b) shows that the quantization errors for the orthonormal basis functions can be significantly reduced. For different orthonormal basis functions, the quantization errors are about the same.