Method/apparatus for an accelerated response to resource allocation requests in a CDMA push-to-talk system using a CDMA interconnect subsystem to route calls

An apparatus for providing an accelerated response to a push-to-talk origination message in a dispatch system, said dispatch system having a plurality of remote units, a plurality of base stations, and a mobile system controller, said apparatus comprising:

• a pre-allocated first set of equipment for communicating with a first remote unit;
• a pre-allocated second set of equipment to support said push-to-talk connection at said mobile system controller;
• a first base station for receiving said push-to-talk origination message, and directly in response transmitting a page to said first remote unit indicative of said pre-allocated modulator/demodulator through which to communicate;
• a CDMA interconnect subsystem for routing calls between said plurality of base stations and said mobile system controller;
• a central call processor, located at said mobile system controller, for pre-allocating said modulator/demodulator located at each of said plurality of base stations.

A method of providing an accelerated response to a push-to-talk origination message in a dispatch system, said dispatch system having a plurality of remote units, a plurality of base stations, and a mobile system controller, said method comprising the steps of:

• pre-allocating a first modulator/demodulator at each of said plurality of base stations for providing a forward broadcast link to said plurality of remote units and for providing a reverse traffic link to a first remote unit;
• pre-allocating a first set of equipment to support said accelerated response at said mobile system controller;
• receiving at a first base station said push-to-talk origination message from said a first remote unit;
• transmitting from said first base station directly in response to said push-to-talk origination message a page to said first remote unit directing said first remote unit to establish a communication link through said pre-allocated first modulator/demodulator and said first set of equipment;
• allocating a second modulator/demodulator at said first base station and a second set of equipment at said mobile system controller;
• and
• transferring said communication link to said second modulator/demodulator and said second set of equipment and terminating said communication link to said pre-allocated first modulator/demodulator and said first set of equipment wherein the step of pre-allocating said set of equipment comprises the step of pre-allocating at least one mobile system controller selector to route calls between a switch and a CDMA interconnect subsystem.

An apparatus for providing an accelerated response to a push-to-talk origination message in a dispatch system, said dispatch system having a plurality of remote units, a plurality of base stations, and a mobile system controller, said apparatus comprising:

• a pre-allocated modulator/demodulator at each of said plurality of base stations for providing a forward broadcast link to said plurality of remote units and for providing a reverse traffic link for use by a first remote unit;
• a pre-allocated set of equipment at said mobile system controller to support said accelerated response to said push-to-talk origination message;
• a second modulator/demodulator, located at each of said plurality of base stations, for accepting a communication in progress between said first remote unit and said pre-allocated modulator/demodulator;
• a second set of equipment at said mobile system controller for accepting said communication from said first set of equipment;
• a first base station in communication with said first remote unit for requesting said second modulator/demodulator and said second set of equipment upon receipt of said push-to-talk origination message;
• a central call processor for pre-allocating said pre-allocated modulator/demodulator and for allocating a second modulator/demodulator upon request from said first base station;
• and
• means for switching communications from said first modulator/demodulator and said pre-allocated set of equipment to said second modulator/demodulator and said second set of equipment wherein said pre-allocating set of equipment comprises at least one selector located at said mobile system controller for routing calls between a switch and a CDMA interconnect subsystem.