Bae Systems Information and Electronic Systems Integration Inc.

Future Wei Technologies, Inc.

Lsi Corporation

Agere Systems Inc.

Naresh Chand

Bruce M Eteson

Jianjun Yu

Keisuke Kojima

Stanley K Pau

Ning Cheng

Lei Jing

Kevin M McNeill

Peter Ossieur

Daniel Taskalos

An optical network system comprising an optical line terminal (OLT) and an optical network unit (ONU) coupled to the OLT and configured to communicate with the OLT via an optical signal. At least one of the OLT or the ONU comprises a closed-loop gain controlled transimpedance amplifier (TIA) comprising a first amplifier configured to receive an input signal, generate a main output signal by amplifying the input signal according to a gain factor of the first amplifier, and generate an auxiliary output proportional to the input signal, an average detector coupled to the first amplifier and configured to receive the auxiliary output, and determine an average of the input signal according to the auxiliary output, and a feedback loop coupled to the first amplifier and the average detector and configured to control the gain factor of the first amplifier according to the average of the input signal.

Closed-loop automatic gain control in linear burst-mode transimpedance amplifier

Methods, systems and other embodiments associated with a laser communication system using a single wavelength are presented. A first data is modulated onto an RF carrier to produce a modulated RF carrier. A laser is intensity modulated using with the modulated RF carrier. The intensity modulated laser beam is transmitted from an interrogator to a modulating retro-reflector (MRR) terminal. A portion of the laser beam is received at a receiver at the MRR terminal. Another portion of the laser is modulated at the MRR terminal with a second data to produce a re-modulated laser beam. The re-modulated laser beam is reflected back to the interrogator.

Full-duplex laser communication using single wavelength from an optical transmitter

A communication network includes a local area network (LAN) and a wireless access point coupled to the LAN. In one embodiment, each access point includes a medium access control (MAC) stage, and a radio frequency (RF) transmitter/receiver for communicating unsecure message data via RF links with users of associated wireless devices. An optical transmitter/receiver in the access point enables the users to communicate secure message data over the LAN via free space optical (FSO) links with the users. The MAC stage operates (i) to direct unsecure data from the LAN to the wireless device users and to direct unsecure data from the users to the LAN, via the RF transmitter/receiver; and (ii) to direct secure data from the LAN to the wireless device users and to direct secure data from the users to the LAN, via the optical transmitter/receiver. An integrated VoIP/FSO portable handset is also disclosed.

Communication network with secure access for portable users

A fiber optic link for platforms with data sources including, e.g., sensors, cameras, radars and antennas. An array of optical transmitter/receiver pairs is coupled to an integrating network of the platform. Data modules are each coupled to certain ones of the data sources and include a receiver for detecting control data, and a modulator for modulating a light signal according to signals from the module's data sources. At least one optical fiber is coupled between a given transmitter/receiver pair of the array, and a corresponding data module. A laser source associated with each transmitter supplies a light signal with the control data to a corresponding data module downstream over an optical fiber. The light signal is modulated by the signals from the module's data sources, and the modulated light signal is returned to an array receiver upstream over an optical fiber.

Bi-directional optical link between multiple data sources and a processing node in an avionics platform

Methods and apparatus for providing improving optical signal transmission results over standard mode fiber using a combination of negative chirp, low extinction ratio, and self-phase modulation transmission techniques in combination are described. The use of pre-transmission signal distortion in combinations with one or more of the other transmission techniques is also described. Pre-transmission signal distortion may be introduced by controlling a modulator with a large symmetric AC signal which causes the modulator to operation in a non-linear region or, alternatively, by using a relatively small non-symmetric AC signal to drive the modulator. Use of the small non-symmetric signal has the advantage of reduced power requirements. The pre-transmission distortion acts to counter some of the distortion introduced by the transmission of the signal over an optic fiber.

Methods and apparatus for optical data transmission over standard fiber

Methods and apparatus for providing a time slot switch which performs switching in the optical domain without the need for O-E-O conversion is described. The time slot switching device of the present invention may be part of a large switching device capable of performing switching and other function on WDM, TDM and WDM signals which are time division multiplexed. An optical time slot switch implemented using a time slot demultiplexer, optical cross-connect, variable delay lines and time slot multiplexer are described. Frequency conversion may be performed on a per time slot basis in cases where time slot signals are switched between lines using different wavelengths. Wave division demultiplexers and multiplexers can be added to the basic time slot switch to provide support for WDM switching and switching of TDM signals which are transmitted using wave division multiplexing.

Growing community of inventors

Warren, NJ, United States of America

Naresh Chand