Compander characteristics

The Compander parameters (Bell, 1971) are Compression Ratio and Unaffected Level, where compressor and expander power output are given by Equations 20.36 and 20.37.

K is normally 2 (the Compression Ratio) and KA equal 5 (the Unaffected Level). Compander characteristics are as in Figure 20.16.

The values for K and KA are limited by practical considerations. Increasing these values will improve the noise reduction but at the expense of other transmission properties. For instance increasing the compression ratio has the disadvantage of expanding any gain change or level error within the transmission.