Patent Application
20050101339
Not applicable
This invention relates generally to audio storage, and more particularly to a system and method for recursively storing audio in one or more among a portable communication radio, a base station or a communication switch for subsequent retrieval.
Telecommunication systems are subject to interference and other anomalies that corrupt audio being sent to or received by the user. In half-duplex communication (i.e. dispatch), there is no feedback if the audio is garbled, missed, or corrupted. Thus, vital information can be missed without having any means of effectively retrieving or re-creating information that has been sent.
Existing cellular phones, dispatch radios, and other telecommunication devices contain ample amounts of memory that can be utilized to store digital or analog audio. Additionally, the base station is capable of storing virtually unlimited amounts of sampled audio. There are numerous devices that store voice in a subscriber unit as discussed in U.S. Pat. No. 6,580,903 by Hein et al. For example, there are several paging devices and cellular phones that store voice (see U.S. Pat. No. 5,455,579 by Bennett et al). There are also dispatch radio systems that provide voice mail service as discussed in U.S. Pat. No. 5,711,011 by Urs et al. None of these existing systems store voice for the purpose of retrieving real-time or near real-time voice or data.
A method and apparatus for recursively storing audio in a communication system can resolve or alleviate many of the issues experienced by dispatched radio users when subject to interference and other anomalies that corrupt the audio.
In one embodiment of the present invention, a method of recursively storing audio in a communication system can comprise the steps of recursively storing audio in at least one among a transmitting subscriber unit, a receiving subscriber unit, and a communication switch in remote communication with the transmitting subscriber unit and selectively retrieving audio previously transmitted by the transmitting subscriber unit. The stored audio can be retrieved at the request of the receiving or transmitting subscriber unit from at least one among the receiving or transmitting subscriber unit and the communication switch. The audio signal can be a dispatch radio signal that can be stored at a dispatch application processor forming part of the communication switch. The step of retrieving can include the step of retrieving a most recent dispatch signal stored at the communication switch upon a user request of the receiving subscriber unit or upon determining a received signal quality level below a predetermined threshold at the receiving subscriber unit.
In a second aspect of the present invention, a communication system can include a first portable communication unit operating in a dispatch mode with at least a second portable communication unit and an infrastructure system providing a communication link between the first portable communication unit and at least the second portable communication unit. The infrastructure system can include a memory for recursively storing a most recent audio stream from at least one among the first portable communication unit and at least the second portable communication unit. The infrastructure system can further include a dispatch application processor. The communication system can further include a means for retrieving a most recent dispatch signal stored at the infrastructure system upon determining a received signal quality level below a predetermined threshold at the second portable communication unit or upon a user request of at least one among the first portable communication unit and the second portable communication unit. The memory can store audio indefinitely until a subsequent audio stream overwrites the stored audio. The memory can also be optimized by sampling and compressing the stored audio stream.
In a third aspect of the present invention, a portable communication device can include a transceiver operating as a dispatch radio and a processor coupled to the transceiver. The processor can be programmed to request a retransmission of a recently transmitted audio stream from a memory in an infrastructure system serving the portable communication device and to receive the retransmission of the recently transmitted audio stream. The processor can also be programmed to automatically request the retransmission upon determining a received signal quality level below a predetermined threshold or upon a user request.
Referring to
Operationally, embodiments in accordance with the invention can store sampled audio segments for replay upon user request or upon other predetermined events. A user's telecommunication device or another device in the communication link could recursively store streams of audio. Upon detection of an error, anomaly, or user request, the previous stream of audio could be replayed.
Referring to
Operationally, the portable communication device 52 in the form of a phone receives (and transmits) audio from communication system 50. This audio would be transmitted into the phone and stored recursively as determined by memory and phone settings. The received audio would be replayed upon user request or upon detecting a lack of a minimum quality level. The audio can be indefinitely accessible until the next audio stream overwrites it. Phone settings and available memory would determine the amount and quality of the stored audio. Additionally, sampling and compression techniques could be used to optimize this invention. The memory location for storing in the recursively stored audio can be maintained at the transmitting phone, the infrastructure system, or the receiving phone.
Referring once again to
Referring to
In light of the foregoing description, it should be recognized that embodiments in accordance with the present invention can be realized in hardware, software, or a combination of hardware and software. A method and system for secure communications in a communication device according to the present invention can be realized in a centralized fashion in one computer system or processor, or in a distributed fashion where different elements are spread across several interconnected computer systems or processors (such as a microprocessor and a DSP). Any kind of computer system, or other apparatus adapted for carrying out the methods described herein, is suited. A typical combination of hardware and software could be a general purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein.
Additionally, the description above is intended by way of example only and is not intended to limit the present invention in any way, except as set forth in the following claims.
