A new Switched Product Code Pyramid Vector Quantizer (SPCPVQ) used for quantizing the ISF (Immittance Spectral Frequencies) parameters of wideband speech is proposed in this paper.Based on switch vector quantization and product code pyramid vector quantization

in this quantizer

the ISF parameters vector to be quantized is first switched to one of the possible directions and then quantized using the corresponding product code pyramid vector quantizer.The characteristics of this Algorithm are low complexity and low memory for the codebook storage.Experimental results show that this quantization scheme achieves lower spectral distortion with transparent coding at 46bits/frame.