06792030 is referenced by 3 patents.

The invention provides a method and apparatus for establishing a non-obtrusive data channel within a voice communication channel to transmit data during an audio transmission without disruption. This audio transmission can be for example, an audio conversation between a first and a second party. The invention uses spread spectrum modulation to hide the reception and transmission of data from the first and second party and allow the ongoing conversation to proceed uninterrupted. In a preferred embodiment, the invention is used to provide an enhanced call waiting feature whereby caller identifying (ID) information of a third party is transmitted over a telephone line from a local central office (CO) to a first party engaged in a telephone conversation with a second party. Advantageously, the use of spread spectrum modulation to transmit data in a voice channel carrying a telephone conversation prevents any interruption in the on-going conversation and does not result in any noticeable disruption.

Method and apparatus for delivering non-obtrusive data services by spread spectrum modulation
Application Number
Publication Number
6792030 (B2)
Application Date
October 5, 1999
Publication Date
September 14, 2004
Frederic Simard
Michael C G Lee
Nortel Networks
H04B 1/69
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