A signal receiving apparatus includes at least one signal separating apparatus that separates a specific signal from a plurality of received signals. Each of the at least one signal separating apparatus includes a spatial filtering unit that separates at least one equalized signal and a decision signal outputting unit that generates a first decision signal by deciding the equalized signal and outputs the generated first decision signal. The spatial filtering unit separates the at least one equalized signal by multiplying at least the plurality of received signals among the plurality of received signals and either the first decision signal output from the decision signal outputting unit or a second decision signal output from another signal separating apparatus by predetermined weighting coefficients.

A signal receiving apparatus includes at least one signal separating apparatus that separates a specific signal from a plurality of received signals. Each of the at least one signal separating apparatus includes a spatial filtering unit that separates at least one equalized signal and a decision signal outputting unit that generates a first decision signal by deciding the equalized signal and outputs the generated first decision signal. The spatial filtering unit separates the at least one equalized signal by multiplying at least the plurality of received signals among the plurality of received signals and either the first decision signal output from the decision signal outputting unit or a second decision signal output from another signal separating apparatus by predetermined weighting coefficients.

The signal detection device includes the signal detection unit that derives the estimation vector of the transmission signal vector,

the first conversion unit that converts the estimation vector of the transmission signal vector to the estimation vector of the transmission signal vector based on the reduced basis, the first determination unit that converts the estimation vector of the transmission signal vector based on the reduced basis to the determination value vector of the transmission signal vector, the first update unit that updates the separation matrix, the second conversion unit that converts the first error signal vector to the second error signal vector based on the reduced basis, the second update unit that updates the error covariance matrix based on the reduced basis, the second determination unit that determines whether or not the predetermined condition is satisfied, and a third update unit that updates the unimodular matrix, the inverse matrix of the unimodular matrix, and the error covariance matrix based on the reduced basis when it is determined that the predetermined condition is established.

The signal detection device includes the signal detection unit that derives the estimation vector of the transmission signal vector,

the first conversion unit that converts the estimation vector of the transmission signal vector to the estimation vector of the transmission signal vector based on the reduced basis, the first determination unit that converts the estimation vector of the transmission signal vector based on the reduced basis to the determination value vector of the transmission signal vector, the first update unit that updates the separation matrix, the second conversion unit that converts the first error signal vector to the second error signal vector based on the reduced basis, the second update unit that updates the error covariance matrix based on the reduced basis, the second determination unit that determines whether or not the predetermined condition is satisfied, and a third update unit that updates the unimodular matrix, the inverse matrix of the unimodular matrix, and the error covariance matrix based on the reduced basis when it is determined that the predetermined condition is established.

A communications system comprises a maximum ratio combining (MRC) circuit for receiving a plurality of input data streams and for processing the plurality of input data streams using maximum ration combining to improve signal to noise ratio. A MIMO transmitter transmits the MRC processed carrier signal over a plurality of separate communications links from the MIMO transmitter, each of the plurality of separate communications links from one transmitting antenna of a plurality of transmitting antennas to each of a plurality of receiving antennas at a MIMO receiver.

An injection locked transmitter for an optical communication network includes a master seed laser source input substantially confined to a single longitudinal mode, an input data stream, and a laser injected modulator including at least one slave laser having a resonator frequency that is injection locked to a frequency of the single longitudinal mode of the master seed laser source. The laser injected modulator is configured to receive the master seed laser source input and the input data stream, and output a laser modulated data stream.

An injection locked transmitter for an optical communication network includes a master seed laser source input substantially confined to a single longitudinal mode, an input data stream, and a laser injected modulator including at least one slave laser having a resonator frequency that is injection locked to a frequency of the single longitudinal mode of the master seed laser source. The laser injected modulator is configured to receive the master seed laser source input and the input data stream, and output a laser modulated data stream.

Optical communication system communicates between an array of originating tiles and an array of terminating tiles. Each array is associated with a lenslet array, such as a two-layer array. Each originating tile has an array and each terminating tile has an array of transceivers. Each tile is associated with a common lenslet or lenslet pair. A beamlet from a representative originating transceiver passes through the lenslet pair adjacent to its tile via an originating Fourier transform element, collimating optics, and a terminating Fourier transform element. The beam then passes through the lenslet pair adjacent to the tile containing the terminating transceiver associated with the representative originating transceiver, and is focused onto that receiver by that lenslet pair. Originating and/or terminating arrays of multicore fibers may be used between the originating transceivers and the originating Fourier transform element and/or between the terminating Fourier transform element and the terminating transceivers.

The various embodiments provide an optical transmission system comprising an optical transmitter configured to transmit data over an optical fiber transmission channel made of a multi-core fiber, optical signals carrying the data propagate along the multi-core fiber according to two or more cores, the multi-core fiber being associated with fiber parameters and misalignment losses values, wherein the optical transmission system comprises a system administration device configured to determine a core dependent loss value depending on the fiber parameters and misalignment losses values.

A first multimode optical fiber carries a mode division multiplexed (MDM) optical signal. The MDM optical signal is transmitted into a second multimode fiber from the first multimode optical fiber. The first and second multimode fibers are coupled via a fiber connector. The lateral offset between the two fibers at the connector is less than 2 μm.