Efficient LPC Quantization Methods - Digital Speech: Coding for Low Bit Rate Communication Systems - page 115

Table 5.7 MSVQ and SVQ structures for Figure 5.11
Stages MSVQ SVQ

bit allocation Bit allocation Vector split

2 12,12 12,12 5,5

3 8,8,8 8,8,8 3,3,4

4 6,6,6,6 6,6,6,6 3,2,2,3

5 5,5,5,5,4 5,5,5,5,4 2,2,2,2,2

2.5e04 1.8

SVQ codebook
MSVQ codebook

SVQ codebook
MSVQ codebook

1.6

2.0e04

1.4

1.5e04 1.2

1.0

1.0e04

0.8

5.0e05 0.6

2 3 4 5 2 3 4 5

Number of stages Number of stages

15.0

SVQ codebook
MSVQ codebook

10.0

5.0

0.0

2 3 4 5

Number of stages

Figure 5.11 Performance comparison of various SVQ and MSVQ codebook
structures

in Figure 5.12. Outliers at 4 dB have not been plotted, as they are zero for all
cases. The advantage of a TS over both SS and FS is evident in these graphs.
For M greater than or equal to eight, the performance of the TS is very close
to that of the FS, at a much reduced complexity. It is also significantly better
than that of SS, for a relatively small increase in complexity. The complexity