摘要:
The purpose of the present invention is to use chalcogenide glass to produce an infrared transmitting glass that is more suitable for mold-forming than the conventional glasses. Specifically, the invention provides an infrared transmitting glass for mold forming which contains, in molar concentrations, 2-22% of Ge, 6-34% of at least one element selected from the group consisting of Sb and Bi, 1-20% of at least one element selected from the group consisting of Sn and Zn and 58-70% of at least one element chosen from the group comprising S, Se and Te.
摘要:
The purpose of the present invention is to use chalcogenide glass to produce an infrared transmitting glass that is more suitable for mold-forming than the conventional glasses. Specifically, the invention provides an infrared transmitting glass for mold forming which contains, in molar concentrations, 2-22% of Ge, 6-34% of at least one element selected from the group consisting of Sb and Bi, 1-20% of at least one element selected from the group consisting of Sn and Zn and 58-70% of at least one element chosen from the group comprising S, Se and Te.
摘要:
An OFDM reception device including: a first orthogonal transformation unit that orthogonally transforms a signal for a useful symbol duration included in an OFDM signal and outputs a resulting orthogonally transformed signal; a second orthogonal transformation unit that orthogonally transforms a signal for a guard interval duration included in the OFDM signal and outputs a resulting orthogonally transformed signal; a detection unit that detects a wide band carrier frequency error amount according to the signal output from the first orthogonal transformation unit and the signal output from the second orthogonal transformation unit; and a correction unit that corrects a wide band carrier frequency shift of the OFDM symbol according to the wide band carrier frequency error amount detected by the detection unit.
摘要:
A receiver includes a demodulator that demodulates a modulation wave modulated according to orthogonal frequency division multiplexing (OFDM). The demodulator includes an interference wave detector that detects that received modulation wave includes interference wave when received power of each sample of the received modulation wave exceeds a threshold, and upon the detection, executes replacement processing of replacing a received signal exceeding the threshold with a predetermined value, a first interference wave power estimation unit configured to estimate interference wave power included in an OFDM symbol included in the received modulation wave on the basis of the number of samples that have been subjected to the replacement processing, and a demodulated data generator that demodulates the received modulation wave by executing demodulation processing of demodulating the received modulation wave that has been subjected to the replacement processing on the basis of the interference wave power.
摘要:
A receiver includes a demodulator that demodulates a modulation wave modulated according to orthogonal frequency division multiplexing (OFDM). The demodulator includes an interference wave detector that detects that received modulation wave includes interference wave when received power of each sample of the received modulation wave exceeds a threshold, and upon the detection, executes replacement processing of replacing a received signal exceeding the threshold with a predetermined value, a first interference wave power estimation unit configured to estimate interference wave power included in an OFDM symbol included in the received modulation wave on the basis of the number of samples that have been subjected to the replacement processing, and a demodulated data generator that demodulates the received modulation wave by executing demodulation processing of demodulating the received modulation wave that has been subjected to the replacement processing on the basis of the interference wave power.
摘要:
A wideband carrier frequency error calculator that, for each of a plurality of location patterns, calculates a cumulative value through a predetermined process performed on signals output by an orthogonal transformer for a plurality of sub-carrier positions determined according to a given location pattern while simultaneously shifting the signals output therefrom by one sub-carrier unit along the carrier direction and that also calculates wideband carrier frequency error according to carrier direction discrepancies calculated as maximum values within the cumulative value, and a carrier frequency error corrector that applies corrections to carrier frequency discrepancies according to the wideband carrier frequency error so calculated.
摘要:
An OFDM reception device receives an OFDM symbol that includes a signal for a useful symbol duration generated based on transmission information and a signal for a guard interval duration generated based on the signal for the useful symbol duration. The OFDM reception device includes a first orthogonal transformation unit configured to perform an orthogonal transformation on the signal for the useful symbol duration, a second orthogonal transformation unit configured to perform an orthogonal transformation on the signal for the guard interval duration, and a decoding unit configured to decode the OFDM symbol in accordance with results of the orthogonal transformation by the first orthogonal transformation unit and results of the orthogonal transformation by the second orthogonal transformation unit.
摘要:
An OFDM transmitter and an OFDM receiver respectively transmit and receive N (N≧2, N is an integer) control symbols. For each control symbol, a guard interval time-domain signal is, for example, identical to a signal obtained by frequency-shifting at least a portion of a useful symbol time-domain signal by an amount different from any other symbol, or to a signal obtained by frequency-shifting one or both of a portion and a span of a useful symbol interval time-domain signal different from any other symbol by a predetermined amount.
摘要:
A waveform equalizer includes a filter unit, an error estimation unit, a tap coefficient storage unit, and an update amount calculation unit which includes an intermediate calculation unit and an update amount setting unit. Coefficient update amount ΔCi(n) for an ith tap is calculated according to an equation ΔCi(n)=αi(n)×μ×e(n)×x*(n−i) with the multiplication by αi(n) being performed by the update amount setting unit. Here, 0
摘要:
An inter-carrier interface removal device can improve estimation accuracy of inter-carrier interference caused by Doppler shift in a received multi-carrier signal moving at a high speed, and a reception characteristic of the multi-carrier signal after removing the inter-carrier interference. The inter-carrier interference removal device includes a channel estimation unit estimating a channel frequency characteristic according to a carrier signal, an equalization unit equalizing the carrier signal with the channel frequency characteristic and outputs tentative carrier data, a reliability value calculation unit calculating a reliability value according to the channel frequency characteristic, a weighting unit weighting the tentative carrier data with the reliability value, an ICI component estimation unit estimating an ICI component according to the weighted tentative carrier data and the estimated channel frequency characteristic, and an ICI removal calculation unit removing the ICI component from the carrier signal.