Patent ID: 6108560
Filing Date: 2000-08-22
Classification: H04L

Abstract:
A method of setting up a wireless communications link between two subscriber radio stations which each communicate with a respecting base station by the use of a selected one of several codecs;the method comprising:the signalling by each subscriber radio station to the other subscriber radio station of the codecs supported between each subscriber radio station and base station by said each subscriber radio station; anddetermining an appropriate codec for each subscriber radio station and base station pair, as deemed necessary based upon the signalling information,wherein the determination of an appropriate codec is made with reference to data provided in the form of a look-up table;wherein the look-up table takes into account:the codec presently employed by a subscriber radio station in establishing a call;the codecs supported by each subscriber radio station to base station link;the look-up table determining which codecs should be employed between each subscriber radio station and base station; and, changing the codec presently in use by either one or both of the subscriber radio stations as determined by the look-up table wherein, in the instance that the codecs supported between the two subscriber radio stations are common, tandem free operation is established, whereby the quality of the link is maximised.