Emergency call station identification system and method

• US 5,235,630 A
• Filed: 04/17/1991
• Issued: 08/10/1993
• Est. Priority Date: 04/17/1991
• Status: Expired due to Term

• Current Assignee: Amcom Software, Inc. (Spok Holdings, Inc.)
• Original Assignee: Telident, Inc. (MedTel Services LLC)
• Inventors: Osgood, Gordan, Madson, Donald, Moody, Martin
• Primary Examiner(s): Dwyer, James L.
• Assistant Examiner(s): Chan, Jason
• Application Number:
  US07/686,492
• Time in Patent Office: 846 Days
• Field of Search: 379/37, 379/45, 379/49, 379/39-44, 379/201
• US Class Current: 379/37
• CPC Class Codes: H04M 2242/04 for emergency applications
• CPC Class Codes: H04M 2242/06 Lines and connections with preferential service
• CPC Class Codes: H04M 2242/22 Automatic class or number identification arrangements
• CPC Class Codes: H04M 3/42042 Notifying the called party of information on the calling party details within substation equipment H04M1/57, signalling details H04Q3/72
• CPC Class Codes: H04M 3/42314 in private branch exchanges
• CPC Class Codes: H04Q 3/72 Finding out and indicating number of calling subscriber

Abstract

A device for identifying a specific station, among a plurality of geographically-dispersed stations represented by a common phone number and serviced by a common PBX, which has initiated an emergency "9-1-1" telephone call. The specific station having initiated the call is identified to the appropriate public safety answering point (PSAP) which is connected in an enhanced "9-1-1" emergency call network. Typically, the PSAP and PBX have different protocols. The device functions to convert the protocol of the PBX to the protocol of the emergency call network. Further, it assigns an arbitrary designation representing the specific station identified as having initiated the emergency call. Further, the invention transmits the arbitrary designation to the appropriate PSAP for responding to the call.

Claims

1. A method for harmonizing the protocol of a private branch exchange (PBX), servicing a plurality of stations, with the protocol of an enhanced "9-1-1" emergency call network, wherein the PBX is provided with a plurality of connections, and wherein a switching tandem of the emergency call network is also provided with a plurality of connections, comprising the steps of:

(a) providing a harmonization module having a first plurality of connections corresponding in type and number to the connections of the PBX, and a second plurality of connections, corresponding in type and number to the connections of the switching tandem;

(b) interconnecting the connections of the PBX with the corresponding first plurality of connections of said harmonization module by employment of a plurality of tie-line interconnections;

(c) interconnecting the connections of the switching tandem with the corresponding second plurality of connections of said harmonization module by employment of a plurality of trunk interconnections;

(d) exercising a connection of the PBX in response to transmission of a signal indicative of initiating of an emergency call by a specific station serviced by the PBX;

(e) sensing the exercise of the PBX connection at the corresponding connection of the harmonization module;

(f) seizing a trunk interconnecting a connection of said harmonization module and a corresponding connection of the switching tandem;

(g) causing the switching tandem to respond to said harmonization module;

(h) sensing the response of the switching tandem at the harmonization module; and

(i) relaying existence of the response of the switching tandem to the PBX.

2. A method in accordance with claim 1 further comprising the steps of:

(j) transmitting from the PBX specific identification information regarding the station serviced by the PBX which has initiated a "9-1-1" emergency call to the harmonization module;

(k) translating the information to an arbitrary designation representative of the specific station; and

(l) transmitting the arbitrary designation to the switching tandem.

3. A method in accordance with claim 2 further comprising the steps of:

(m) acknowledging to the harmonization module receipt of the arbitrary designation by the switching tandem; and

(n) acknowledging to the PBX receipt of the arbitrary designation by the switching tandem.

4. A method in accordance with claim 3 further comprising the step of:

(o) defining a voice path from the PBX to the switching tandem.

5. A method in accordance with claim 4 further comprising the step of:

(p) monitoring discontinuation of the voice path.

6. A method in accordance with claim 2 further comprising a step, after performance of step (j), of transmitting network call directing information to the switching tandem.

7. A method for harmonizing the protocol of a private branch exchange (PBX), servicing a plurality of stations, with the protocol of an enhanced "9-1-1" emergency call network, wherein the PBX is provided with a plurality of connections, and wherein a receiving apparatus of the emergency call network is also provided with a plurality of connections, comprising the steps of:

(a) providing a harmonization module having a first plurality of connections corresponding in type and number to the connections of the PBX, and a second plurality of connections, corresponding in type and number to the connections of the receiving apparatus;

(b) interconnecting the connections of the PBX with the corresponding first plurality of connections of said harmonization module by employment of a plurality of tie-line interconnections;

(c) interconnecting the connections of the receiving apparatus with the corresponding second plurality of connections of said harmonization module by employment of a plurality of trunk interconnections;

(d) exercising a connection of the PBX in response to transmission of a signal indicative of initiating of an emergency call by a specific station serviced by the PBX;

(e) sensing the exercise of the PBX connection at the corresponding connection of the harmonization module;

(f) seizing a trunk interconnecting a connection of said harmonization module and a corresponding connection of the receiving apparatus;

(g) causing the receiving apparatus to respond to said harmonization module;

(h) sensing the response of the receiving apparatus at the harmonization module; and

(i) relaying existence of the response of the receiving apparatus to the PBX.