A synchronized pattern sequence system including a processor and a timing receiver configured to receive a time reference signal to set a time of the electronic device. The system further includes sequence receiver configured to receive a sequence pattern and a timing for presenting the sequence pattern and a pattern indicator configured to present the sequence pattern. The system also has a memory and machine-readable code stored in the memory. The machine-readable code is configured to cause the processor to direct the pattern indicator to present the sequence pattern as a recognizable pattern according to the received timing in synchronization with the sequence pattern presented on at least one other electronic device.

Disclosed in some examples, are optical devices, systems, and machine-readable mediums that send and receive multiple streams of data across a same optical communication path (e.g., a same fiber optic fiber) with a same wavelength using different light sources transmitting at different power levelsthereby increasing the bandwidth of each optical communication path. Each light source corresponding to each stream transmits at a same frequency and on the same optical communication path using a different power level. The receiver differentiates the data for each stream by applying one or more detection models to the photon counts observed at the receiver to determine likely bit assignments for each stream.

An optical transmission method (10) comprising steps of receiving (12) a communication signal comprising symbols for transmission. The method comprises performing (16) linear amplitude modulation of an optical carrier with the communication signal to generate an amplitude modulated optical carrier. The method comprises performing low-pass filtering (14) to reduce a bandwidth of the symbols to less than a Nyquist bandwidth of the symbols. The method comprises transmitting (18) the amplitude modulated optical carrier. The method further comprises receiving (20) the amplitude modulated optical carrier following transmission and performing direct detection of the received amplitude modulated optical carrier to generate a received electrical signal; and determining (22) received symbols from the received electrical signal using an indication of a nonlinear impulse response of the direct detection.

A transimpedance amplifier converts an input current to a differential signal and outputs the differential signal. The transimpedance amplifier includes a single-ended amplifier configured to convert a current signal to a voltage signal, a first feedback circuit configured to generate a bypass current, a differential amplifier circuit configured to generate the differential signal in accordance with the difference between the voltage signal and a reference voltage signal, and a detector circuit configured to detect a start and an end of a burst optical signal. The detector circuit detects the end of the burst optical signal based on a peak value of the positive-phase component and a peak value of the negative-phase component and switches the time constant of the first feedback circuit from a first time constant to a second time constant smaller than the first time constant in response to detecting the end of the burst optical signal.

Disclosed in some examples are methods, systems, optical devices, and machine readable mediums for utilizing uncertainty ranges along with ECC in power level modulation schemes. Photon counts within the uncertainty ranges are not demultiplexed and the data is recovered later by the ECC algorithm without retransmissions. This improves performance by reducing error rate by changing demultiplexing behavior to take advantage of characteristics in the ECC algorithms.

Disclosed herein are methods, devices, and system for beam forming and beam steering within ultra-wideband, wireless optical communication devices and systems. According to one embodiment, a free space optical (FSO) communication apparatus is disclosed. The FSO communication apparatus includes an array of optical sources wherein each optical source of the array of optical sources is individually controllable and each optical source configured to have a transient response time of less than 500 picoseconds (ps).

Disclosed herein are methods, devices, and system for beam forming and beam steering within ultra-wideband, wireless optical communication devices and systems. According to one embodiment, a free space optical (FSO) communication apparatus is disclosed. The FSO communication apparatus includes a semiconductor optical device configured to have a transient response time of less than 500 picoseconds (ps), a lens, and a first band select filter.

A circuit detects a digital pattern with a first counter having an input receiving a digital pattern, and an output providing an output signal after detecting a first number of pulses during a first time period. A latch has an input coupled to the output of the first counter for latching the output signal of the first counter. A second counter has an input receiving the digital pattern, and an output providing an output signal after detecting a second number of pulses during a second time period. A logic gate has a first input coupled the output of the first counter, and a second input coupled to the output of the second counter, and an output coupled to the input of the latch. An amplitude detection circuit has an input coupled for receiving the digital pattern and an output coupled to the input of the first counter.

A waveform matching based optical digital signal receiving device sequentially comprises an optical arbitrary waveform generator unit, an electro-optic modulator unit, an opto-electric converter unit, an electric filter unit, a sampling and judging module, a digital signal processing unit and a bit-timing extracting module. Accordingly, signal matched filtering, sampling and judgment can be effectively carried out in the optical domain, and the influence of noises on signal reception can be eliminated to the maximum extent, thereby achieving accurate detection and reception of signals. Meanwhile, compared with a conventional electric receiving device, the digital signal receiving device provided by the present invention breaks the limitation of electronic bottleneck, and greatly improves the bandwidth of signal reception, which allows digital signal reception at a higher speed.

To provide an optical receiver that can economically obtain error correction capability equivalent to or greater than capability based on an error correction code. An optical receiver 2 includes: an optical branching unit 12 that branches a received optical signal into three optical signals, and outputs the optical signals; three of a first, a second, and a third optical receiving circuits 13, 14, and 15 each of which inputs one of the three branched optical signals, operates independently, and performs signal processing including an identification and reproduction process concerning an input optical signal and an error correction process based on the error correction code; and a bit determining circuit 19 that performs, in a bit unit, majority-decision determination on three signals on which error correction processes have been performed and that are output respectively from each optical receiving circuit.