At+t Corp.

Ncr Corporation

At&t Intellectual Property I, LP

Lucent Technologies Inc.

Joel I Javitt

Christopher Lee Rutledge

J Frederick Stevenson

Matthew J Sherman

Edward Wronka

A method for communicating data in a wireless communications system having a base station communicating to at least one of a plurality of terminals over a set of carrier frequencies, the method comprising periodically monitoring the carrier energy level of each said carrier frequency received at a given terminal to identify a list of optimal frequencies over which the carrier energy level is strong enough to maintain a viable transmission from said base station to said given terminal, wherein said viable transmission provides a given coding gain; and simultaneously transmitting a given set of packet data from said base station to said given terminal over a plurality of frequencies from said list of optimal frequencies identified for said given terminal.

Method and apparatus for transmitting high rate packet data over underutilized virtual circuits

Method and apparatus for transmitting high rate packet data over under-utilized virtual circuits

Methods and apparatus for safe and reliable telecommunication using a telecommunication network that employs substantially unguided, free-space, point-to-point, electro-magnetic radiation are provided. Most methods include the use of a retro-reflector near a transceiver assembly. The retro-reflector can be used to rapidly calibrate, align, and/or realign one or more assemblies by reflecting a beam of light back toward its source, providing an opportunity for optical detection of the reflected beam.

Transceiver positioning in free-space optical networks

Apparatus for improving the signal to noise ratio in wireless communication systems through message pooling including hardware, software and protocol contained within a packet data communication system which enables a wireless communication system, for example an electronic display system, to adapt communication techniques to meet customer based accuracy requirements independent of changes in the signal to noise ratio of the communication channel and methods of using the same. Communication having low signal to noise ratios are improved using intelligent retransmissions of the communication signals and statistical detection or demodulation. Such techniques are particularly useful when used in wireless communication in unbalanced systems, such as electronic display systems.

Apparatus for improving the signal to noise ratio in wireless communication systems through message pooling

Free-space, line-of-sight, electro-magnetic communication (i.e., via light or microwaves) is employed to provide a wide range of communication services to geographically scattered users. A relay point or end point is typically associated with each user. Each relay point receives and retransmits information via line-of-sight communication. The end points are also receivers and transmitters of information via line-of-sight communication. Although spaced from one another, the relay and end points are close enough to one another to communicate via line-of-sight links. Hard-wired connections to the users are therefore unnecessary. Broadcast radio frequency communication capability may be provided as a backup for maintaining at least some service in the event of line-of-sight communication failure or interruption. This radio capability may additionally be used to provide cellular communication service to small cells associated with the relay and end points.

Multi-hop telecommunications system and method

An optical transceiver that is particularly adapted for free-space optical telecommunication uses the same optical path for received and transmitted light to a large extent to avoid duplication of optical elements. Received light is split so that different portions can be sent to physically spaced photodetectors, one of which is for detecting optically received information, and others of which are for detecting misalignment of the transceiver. In this way, the alignment detectors do not interfere with light reception by the information detector.

Optical transceiver using common optical path for transmission and

Apparatus for improving the signal to noise ratio in wireless

A method and apparatus for detecting the presence of objects such as persons in front of a high-frequency communications antenna comprising a transmitting element connected to a circulator. The circulator is connected to an antenna system which transmits the signal pursuant to a designated communications or other application. The circulator is also connected to a regulator circuit which measures a reflected signal received from the circulator. The regulator circuit thereupon initiates a reduction or termination in power from the transmitting element, and/or initiates an alarm, when the regulator circuit detects a reflected signal having a magnitude indicating the presence of the object to be detected.

Integrated proximity detector for antennas

A system and method for improving the reliability and performance of wireless communication systems having low signal to noise ratios using intelligent retransmissions of the communication signals and statistical detection or demodulation of signal and background noise levels. Using a combination of hardware, software and a communications protocol in a packet data communication system, a wireless communication system, such as for an electronic display system, adapts communication techniques to meet customer based accuracy requirements independent of changes in the signal to noise ratio of the communication channel.

System and method for improving reliability and performance of wireless

Free-space optical transmission of analog information is facilitated by transmitting constant-amplitude pilot information with the other information. The amount of attenuation of the pilot information at the receiver is detected and used to control the amount by which received information is amplified. In this way the deleterious effects of free-space optical attenuation are substantially eliminated. The pilot information may be transmitted either via its own separate light frequency or wavelength, or as a distinguishable part of a larger quantity of information that is used to modulate one light frequency or wavelength.

Automatic gain control for free-space optical telecommunications links

A wireless communications system and method for providing simultaneous multi-channel packet data communications to a single user for given services without compromising system performance and efficiency. The system has at least one base station that transmits to at least one of a plurality of receiver stations over a given set of carrier frequencies, wherein each base station keeps of list of optimal frequencies over which a given receiver station would reliably receive data packets transmitted from the base station without the need for an increase in carrier energy. In one embodiment the system maintains a queue for each terminal to which data packets will be delivered. The data packets can be delivered over voice-dedicated and/or data packet dedicated frequencies at one time. In any event, however, when transmitting on voice-dedicated frequencies, the queued data packets are transmitted during voice inactivity periods. In another embodiment, both the base station and the receiver stations or terminals are capable of transmitting different packet data simultaneously over different frequencies.

Method and apparatus for transmitting high rate packet data over

A communications system providing a means for dynamically controlling system performance during times when communications traffic substantially changes to prevent blocking service while maintaining communications quality. The communications system provides such dynamic control for voice and/or video communications. For example, a voice communications system according to the present invention provides a means for increasing the effective voice capacity during times of increased voice traffic in a given service area, and decreasing the effective voice capacity during time of decreased voice traffic, wherein the decrease in the effective voice capacity provides an increase in voice quality. In one illustrative embodiment, when the voice traffic increases to a given threshold level, the system implements speech compression on selected channels to increase the effective capacity to that service area. In another embodiment, the system combines two compressed channel into one to increase the effective capacity even further.

Method for dynamic allocation of voice and image compression

A low cost solution for providing wireless multi-rate packet data communications between a transmitting unit and a receiving unit on a single spread spectrum channel. The transmitting unit and receiving unit are operable to change communications modes at any given time to provide packet data communications at any given data rate for any given duration. In general, the transmitting unit is operable to change the coding gain of the transmitted spread spectrum to establish a communications mode providing a given data rate for communication to the receiving unit. In one embodiment, the transmitting unit first establishes a regular communications mode, wherein the transmitting unit generates a spread spectrum packet data signal having a high coding gain, thus providing low rate, highly reliable communications over the channel. Then, at any given time, the transmitting unit sends an escape sequence instructing the receiver to switch to a temporary communications mode, wherein the transmitting unit generates a signal having a lower coding gain, and thus provide a higher data rate for such user services requiring high rate communications.

Growing community of inventors

Hillside, NJ, United States of America

Joel I Javitt