Abstract: A memory stores dummy data including a first data area having more “0” than “1” of a binary logic and a second data area having more “1” than “0” of the binary logic. An ECC processor detects a first error bit number related to the first data area and a second error bit number related to the second data area. A calculator calculates a relative difference of the first error bit number from the second error bit number. A comparator compares the relative difference with a predetermined value. A corrector corrects a read voltage on the basis of a result of comparison by the comparator.

Abstract: A memory stores dummy data including a first data area having more “0” than “1” of a binary logic and a second data area having more “1” than “0” of the binary logic. An ECC processor detects a first error bit number related to the first data area and a second error bit number related to the second data area. A calculator calculates a relative difference of the first error bit number from the second error bit number. A comparator compares the relative difference with a predetermined value. A corrector corrects a read voltage on the basis of a result of comparison by the comparator.

Abstract: A blood pressure measurement apparatus includes circuitry configured to: detect a pulse of a subject, and obtain a photoplethysmography signal; and obtain estimated blood pressure of the subject based on the photoplethysmography signal. The circuitry receives parameter information, generates time information based on the photoplethysmography signal, applies a blood pressure estimation equation to the time information and the parameter information to calculate the estimated blood pressure, receives basic blood pressure information for the subject and the time information, and performs learning processing of applying a learning operational equation to statistical time information, which is obtained by performing statistical processing on the time information, and the basic blood pressure information to update the parameter information.

Abstract: A blood pressure measurement apparatus includes circuitry configured to: detect a pulse of a subject, and obtain a photoplethysmography signal; and obtain estimated blood pressure of the subject based on the photoplethysmography signal. The circuitry receives parameter information, generates time information based on the photoplethysmography signal, applies a blood pressure estimation equation to the time information and the parameter information to calculate the estimated blood pressure, receives basic blood pressure information for the subject and the time information, and performs learning processing of applying a learning operational equation to statistical time information, which is obtained by performing statistical processing on the time information, and the basic blood pressure information to update the parameter information.

Abstract: An analyzing unit sets a threshold on the basis of a target compression ratio of a frame. The compression unit compresses a block having an attribute value larger than or equal to a threshold by applying a first compression format and a block having an attribute value smaller than the threshold by applying a second compression format having a higher compression ratio than the first compression format.

Abstract: A preamble signal is an OFDM signal, and is a real-part signal obtained by removing an imaginary-part signal from a signal in the time domain that is generated by an IFFT process being performed on a signal in the frequency domain obtained by assigning preamble data to subcarriers in accordance with a predetermined arrangement pattern. The predetermined arrangement pattern indicates that preamble data is assigned to any of subcarriers given numbers equal to or less than N/2?1 and the preamble data is not assigned to subcarriers given numbers more than N/2?1, where a plurality of subcarriers are numbered by integers from 0 to N?1 (N is an integer) in ascending order with respect to the center frequency of each subcarrier.

Abstract: A technique capable of improving a packet catch rate when applied to a communication device, for example. An SNR improvement circuit for improving an SNR of an input signal includes a delay unit for delaying the input signal to generate one or more delay signals, and an adder for adding the one or more delay signals and the input signal before being delayed. The input signal contains a periodic signal in which the same signal is repeated a predetermined number of times with a predetermined period. The delay unit generates the one or more delay signals with delay time which is ? times (? is a natural number, and is set at different values with respect to two or more delay signals) longer than the predetermined period.

Abstract: An analyzing unit sets a threshold on the basis of a target compression ratio of a frame. The compression unit compresses a block having an attribute value larger than or equal to a threshold by applying a first compression format and a block having an attribute value smaller than the threshold by applying a second compression format having a higher compression ratio than the first compression format.

Abstract: A communication system includes a first communication device and a second communication device that performs power line communication with the first communication device via an electric power line, wherein the first communication device transmits a plurality of times an initial packet signal added with an error detection code in each of reference timing at regular intervals in the vicinity of zero crossing timing. The second communication device determines whether a reception state is good or poor based on a result of the error detection on each of the received initial packet signals, and when the reception state is poor, the second communication device transmits an ACK signal in timing shifted by micro time from the reference timing after receiving the initial packet signal. Then, the first communication device transmits a data packet signal in timing at the regular interval after the timing of receiving the ACK signal.

Abstract: A transmitter includes a generation section that generates a baseband OFDM signal based on transmission data, and a transmission section that transmits a communication signal that is based on a real-part signal that is obtained by removing an imaginary-part signal from the baseband OFDM signal. In the baseband OFDM signal, the data signal including the transmission data is superimposed on subcarriers that are given numbers equal to or less than N/2?1, and the data signal is not superimposed on subcarriers that are given numbers more than N/2?1, where N (N is an integer) subcarriers included in the baseband OFDM signal are numbered by integers from 0 to N?1 in ascending order with respect to the center frequency of each subcarrier.

Abstract: A preamble signal is an OFDM signal, and is a real-part signal obtained by removing an imaginary-part signal from a signal in the time domain that is generated by an IFFT process being performed on a signal in the frequency domain obtained by assigning preamble data to subcarriers in accordance with a predetermined arrangement pattern. The predetermined arrangement pattern indicates that preamble data is assigned to any of subcarriers given numbers equal to or less than N/2?1 and the preamble data is not assigned to subcarriers given numbers more than N/2?1, where a plurality of subcarriers are numbered by integers from 0 to N?1 (N is an integer) in ascending order with respect to the center frequency of each subcarrier.

Abstract: A technique capable of improving a packet catch rate when applied to a communication device, for example. An SNR improvement circuit for improving an SNR of an input signal includes a delay unit for delaying the input signal to generate one or more delay signals, and an adder for adding the one or more delay signals and the input signal before being delayed. The input signal contains a periodic signal in which the same signal is repeated a predetermined number of times with a predetermined period. The delay unit generates the one or more delay signals with delay time which is ? times (? is a natural number, and is set at different values with respect to two or more delay signals) longer than the predetermined period.

Abstract: A communication system includes a first communication device and a second communication device that performs power line communication with the first communication device via an electric power line, wherein the first communication device transmits a plurality of times an initial packet signal added with an error detection code in each of reference timing at regular intervals in the vicinity of zero crossing timing. The second communication device determines whether a reception state is good or poor based on a result of the error detection on each of the received initial packet signals, and when the reception state is poor, the second communication device transmits an ACK signal in timing shifted by micro time from the reference timing after receiving the initial packet signal. Then, the first communication device transmits a data packet signal in timing at the regular interval after the timing of receiving the ACK signal.