Date Added: Apr 2012
In the current scenario of wireless communication systems, Narrow Band (NB) telephony (having limited BandWidth (BW) of 300 -3400 Hz) offers speech sounding muffled and thin. In order to increase intelligibility and naturalness of recovered speech, NB speech coders should be upgraded to its counterpart WideBand (WB) coders (which supports BW of 50-7000Hz). For the effective utilization of WB speech communication in wireless media, both end devices and network should be made WB compatible which is costly and time consuming. In the mean time some techniques have been developed to artificially extend bandwidth of NB speech to WB at receiver which leads to improvement in the quality of recovered speech.