A common problem faced in the case of wireless to wirelesssubscriber calls in cellular networks is the voice degradation due tothe double encoding/decoding performed at the air interfaces. The voicedegradation is in terms of the voice quality and the significant amountof delay introduced in the voice path. We present some of the methodsemployed in the GMH2000 system for doing away with the extraencoding/decoding step and the problems associated with this. Toovercome this problem in the GMH2000 system the intermediatedecoding/encoding at the base stations (BSSs) is avoided by setting up atransparent data channel between the 2 BSSs for transparently carryingthe compressed voice packaged in inband messages, over the regular 64kbps bit stream. This channel is setup once the call has been completelysetup between the 2 subscribers and no more switch intervention isneeded
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