Efficient implementation of voice processing module with CVSD source coding for tactical wireless systems

Wireless communication systems beyond 3G are characterized by variety of applications which have the requirement of simultaneous transmission/reception of low data rate voice and high data rate video streaming content. Wireless applications such as live video chat requires more bandwidth for transmitting/receiving with high quality. The civilian/COTS cellular wireless systems are very promising and prospective communications systems, but they have several drawbacks from military point of view. Increase in communication range and data security are the major. To increase the range increasing receiver sensitivity is very important. Furthermore, to accommodate uninterrupted voice channel in parallel to video transmission reducing the bandwidth occupancy of voice channel is crucial. To reduce the bandwidth occupancy, several source coding techniques exists. CVSD is one of the best source coding technique for reducing the occupied bandwidth as well as improving receiver sensitivity at baseband level. In this paper, hardware efficient voice communication module with bandwidth efficient CVSD source coding is implemented on FPGA. This module has been integrated in wireless LAN as an additional feature for voice calls without disturbing the video/ data transfer. Improvement in receiver sensitivity for voice channel by using this technique has been observed.