Systems and methods for providing an intelligent network (IN) service to transparently establish a mid-call conference without requiring an intermediate hold state

DETAILED DESCRIPTION To address the above-discussed deficiencies of the prior art, the present invention provides systems and methods related to providing an Intelligent Network (IN) service to transparently establish a mid-call conference using a Mobile Station (MS), without requiring an intermediate hold state of an existing call connection between the MS and a second telephony device.
Using an exemplary method described in detail hereinafter, the IN service is implemented by: i) monitoring for the transmission of dialed digits over a control channel associated with a MS; the dialed digits identifying a third telephony device; ii) establishing a call connection to the third telephony device; and iii) joining the third telephony device in conference with an existing call connection between the MS and a second telephony device, thereby establishing a conference call between the MS and the first and second telephony devices without requiring an intermediate hold state of the existing call connection.
The monitoring operation can be performed by a Mobile-services Switching Center (MSC).
In such embodiments, the monitoring operation is preferably preceded by querying a Home Location Register (HLR) for subscriber information associated with the MS; the subscriber information identifies whether the IN service is to be provided to the MS.
If the IN service is to be provided, the MSC sends an IN service activation request to a Service Control Point (SCP).
The SCP responds by sending Prompt&Collect_User_Information command to the MSC; the command instructs the MSC to monitor a control channel associated with the MS for the transmission of dialed digits from the MS.
Upon receiving dialed digits on the control channel, the MSC sends an acknowledgment message to the SCP; the acknowledgment message includes the dialed digits received over the control channel associated with the MS.
The operation to establish a call connection to the third telephony device can be controlled by the SCP using a resident Service Control Function (SCF)