Mitsubishi Electric Corporation

Mitsubishi Electric Research Laboratories, Inc.

Takafumi Fujimori

Takashi Sugihara

Hideo Yoshida

Tsuyoshi Yoshida

Wataru Matsumoto

Yoshikuni Miyata

Yoshiaki Konishi

Kenya Sugihara

Kiyoshi Onohara

Toshiaki Akino

A transmission device includes an outer code interleaver that generates multiple bit sequences while performing interleaving on a signal formed of multiple multilevel modulation symbols on a per-bit basis, an outer coding unit that performs outer coding processings, in parallel, on the multiple respective bit sequences generated by the interleaving, an outer code deinterleaver that performs deinterleaving on bit sequences obtained by performing the outer coding processings, the deinterleaving being inverse operation of the interleaving performed by the outer code interleaver, an inner coding unit that performs inner coding processings, in parallel, on bit sequences obtained by performing the deinterleaving in the outer code deinterleaver, and an inner code interleaver that performs time interleaving and symbol interleaving on bit sequences obtained by performing the inner coding processings.

Transmission device, reception device, encoding method, and control circuit

An encoding circuit includes: a polar encoding unit capable of encoding a polar code of N bits; a frozen bit adding unit that generates a first sequence by adding frozen bits to an input signal; and a bit arrangement changing unit that: generates a second sequence of N bits by arranging the first sequence in the second sequence according to an arrangement rule dependent on a ratio of Nbits, being a code length of a polar code to be encoded and being N bits or less, and N bits, and setting bit values at bit positions other than positions where the first sequence is arranged in the second sequence to zero when Nbits are less than N bits; and inputs the second sequence to the polar encoding unit. A code word of Nbits is generated by thinning processing based on a result of encoding the second sequence.

Encoding circuit, decoding circuit, and decoding method

A decoding device includes: a hard decision decoder generating a first decoding result by performing hard decision decoding of a polar code using an input signal, and generating a first error detection result by performing first error detection processing on the first decoding result; a soft decision decoder generating a second decoding result by performing successive decoding of a polar code on the input signal, obtained for each decoding step in the successive decoding, and generating a second error detection result by performing second error detection processing on a result obtained by updating the first decoding result using the second decoding result; a data selector selecting and outputting either the first decoding result or the result obtained by updating the first decoding result using the second decoding result; and a controller stopping the soft decision decoder when the data selector outputs the final decoding result.

Decoding device, decoding method, control circuit, and storage medium

A multilevel modulation optical transceiver for distributing an OTN frame defined by ITU-T to a plurality of lanes for transmission, the multilevel modulation optical transceiver including: an MLD transmission unit; and a data replication unit, further including a data rearrangement unit arranged at a preceding stage of the MLD transmission unit, for performing data rearrangement processing of replicating, in advance, a frame synchronization pattern of an overhead of the OTN frame before being subjected to the lane rotation processing from a first lane that has the overhead to another lane that does not have the overhead, and of saving a payload to be overwritten with the frame synchronization pattern to a reserved area of the overhead to enable the payload to be restored on a reception side.

Multilevel modulation optical transceiver and multilevel modulation optical transmission and reception method

A phase of a symbol on an inner or outer circle of a received 8QAM symbol set, which is bitmapped by being assigned one bit depending on whether the symbol is on the inner or outer circle of a constellation mapping diagram and two bits for each of the quadrants, is rotated to generate, by QPSK likelihood generation, along with a likelihood of a received QPSK modulation symbol, a likelihood for the two bits assigned to the quadrant of the 8QAM modulated symbol set whose phase is rotated. Further, the phase-rotated 8QAM modulated symbol set is phase-rotated to the first quadrant of the diagram to move the symbol set to the QPSK symbol mapping positions, thereby generating, by QPSK likelihood generation, the likelihood for the one bit assigned to represent whether the symbol is on the outer circle or the inner circle of the 8QAM modulated symbol set.

Likelihood generation circuit and likelihood generation method

A transmitter for transmitting a transmission signal subjected to modulation after error correction coding and a receiver including a phase compensation unit for receiving the transmission signal and performing demodulation therefor while maintaining synchronization thereof and an error correction decoding unit for performing decoding processing for received data that has been subjected to the demodulation. The transmitter transmits a signal formed of a plurality of pilot sequences as a part of the transmission signal, and the receiver has a phase slip estimation processing function for estimating the phase slip by the phase compensation unit by using the plurality of pilot sequences, and for estimating a phase difference component by the error correction decoding unit, to thereby correct a phase of the received data.

Receiver, transmitter, and communication method

A pre-equalization optical transmitter includes: a tap coefficient selecting unit for saving, in advance, a tap coefficients for generating an RZ pre-equalization signal and an NRZ pre-equalization signal, and for selecting and outputting one of the tap coefficients according to the value of a parameter that is a factor of transmission power fluctuations; a pre-equalization signal generating unit for generating the RZ pre-equalization signal or the NRZ pre-equalization signal based on the tap coefficient; and a modulating unit for generating a pre-equalization optical transmission signal by modulating an optical signal input from a light source by using a signal obtained through D/A conversion and amplification of the RZ pre-equalization signal or the NRZ pre-equalization signal, wherein a transmission method is switched between an RZ method and NRZ method by switching the tap coefficients by the tap coefficient selecting unit.

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Tokyo, Japan

Takafumi Fujimori