Patent Application
20090022084
1. Field of the Invention
The present invention relates to the field of telecommunications. More particularly, the present invention relates to a method and a system for communicating between parties, of which at least one party is an airborne party.
2. Description of Related Art
Conventional communications systems allow radio-frequency (RF) communications between an airborne party, for example, on an airplane, and a ground-based party. Due to the limited radio-frequency (RF) bandwidth available for an aircraft-to-ground link, only a small number of airborne callers can use such a system at any one time. When a particular aircraft-to-ground link is filled to capacity, calls from an aircraft are placed into a queue until a channel becomes available. This is inconvenient for some callers because the purpose of the call was to convey a short message to another party and by being placed in a queue causes the call to take much longer than should be necessary. What is needed is a system that allows an airborne caller to leave a message for a ground-based caller without waiting for an aircraft-to-ground channel to become available. What is also needed is a system that compresses messages, thereby efficiently using the aircraft-to-ground bandwidth.
The present invention provides a method and a communications system that allows airborne callers to leave voice, data, or fax messages for intended recipients who are ground-based. The messages are stored on an airborne platform until sufficient bandwidth becomes available for transmission to a ground-based station. Transmitting messages requires correspondingly shorter air time and results in an efficient bandwidth usage because messages do not require a high degree of interaction between parties. The present invention further provides a system that compresses a stored message before transmission so that aircraft-to-ground bandwidth is used efficiently.
The advantages of the present invention are provided by a method and a communications system that includes a plurality of aircraft telephone units, a control unit coupled to the aircraft telephone units, a memory device that stores messages when communication bandwidth is unavailable, and a transceiver that sends and receives calls and messages to and from ground stations. An airborne party is given the option of storing a message or waiting to place the call directly when sufficient bandwidth becomes available. A stored message can be compressed before transmission and decompressed after reception, making shorter broadcast times possible. The caller is given the option of having a message sent directly to an intended recipient, or to an answering service, and a delivery receipt is transmitted to the originator of the message. Messages can be a voice message, an e-mail message, a fax message, or a data message. The message can be divided into a plurality of packets that are each transmitted separately for further improving efficient bandwidth usage.
The present invention is illustrated by way of example and not limitation in the accompanying figures in which like reference numerals indicate similar elements and in which:
If there is insufficient air-to-ground bandwidth for the call, CTU 2 routes the call to a voice processing circuit 3 that is part of an aircraft data server 13 for recording a short message. Voice processing circuit 3 interacts with a short message processor 4 for handling the message, such as by compressing and/or encrypting the message. Short message processor 4 prompts the caller to begin the message transfer. The message is recorded, compressed and/or encrypted and stored in a message file memory 5. Multiple messages are stored in a message data file.
Short message processor 4 receives availability status air-to-ground bandwidth via a Bearer Services System (BSS) interface (I/F) circuit 8. When sufficient air-to-ground bandwidth becomes available, short message processor 4 instructs a router 6 to deliver message files stored in message files memory 5 to a ground station 11. Router 6 also performs call control functions and, if needed, multiplexing of short message file contents with data from other aircraft data server applications. Data transfer from aircraft data server 8 to the ground station 11 is accomplished via a Bearer Services System 9 and an antenna 10, employing well-known air-to-ground communication system techniques, such as that used by AT&T's North American Terrestrial System (NATS). Ground station 11 forwards the short message file to a short message ground-based server 12 using well-known data communications techniques. Short message server 12 parses the received short message file into the different short messages forming the message file, decompresses and/or decrypts the respective messages and attempts to deliver each respective message to its intended destination 14. That is, voice messages are sent the destination voice terminals and data messages are sent to data terminals. Short message server 12 tracks delivery status of each respective message and provides status information to the message originator as requested by the message originator.
If the caller opted not to store a message at step 23, then the caller can wait in a queue at step 29 until sufficient bandwidth becomes available for placing the call directly to the dialed number at step 30.
This application is a continuation of application Ser. No. 10/211,929, filed Aug. 2, 2002, which is a continuation of application Ser. No. 09/520,806, filed Mar. 8, 2000, which is a continuation of application Ser. No. 08/989,623, filed Dec. 21, 1997, now abandoned, all of which are hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10211929 | Aug 2002 | US |
| Child | 11369449 | US | |
| Parent | 09520806 | Mar 2000 | US |
| Child | 10211929 | US | |
| Parent | 08989623 | Dec 1997 | US |
| Child | 09520806 | US |
