Patents by Inventor Yasunari Ikeda

Yasunari Ikeda has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7505398
    Abstract: A radio relay system (1) comprises a wireless camera (11) and a signal receiving relay station (12). The wireless camera (11) wirelessly transmits signals to the signal receiving relay station (12) by using the OFDM modulation method. The wireless camera (11) and the signal receiving relay station (12) perform energy dispersion at the time of transmission-line-coding/decoding a transport stream. The PRBS seed (initial value) to be used for the energy dispersion can be externally modified and the user can arbitrarily select a value for the seed.
    Type: Grant
    Filed: August 20, 2007
    Date of Patent: March 17, 2009
    Assignee: Sony Corporation
    Inventors: Yoshikazu Miyato, Yasunari Ikeda
  • Patent number: 7447277
    Abstract: An OFDM receiver (1) is provided which includes a clock-frequency error calculation circuit (41) to calculate a difference in clock frequency between a clock for a received signal and an operation clock used in the receiver (1), and a guard correlation/peak detection circuit (12) to determine an autocorrelation of a guard interval and detect a peak timing of the correlation signal. The guard correlation/peak detection circuit (12) incorporates a free-running counter, and outputs a count of the free-running counter at the peak timing to the clock-frequency error calculation circuit (41). The clock-frequency error calculation circuit (41) uses a plurality of time-change rate detection circuits provided at different time intervals to calculate a time-change rate of an input count. The clock-frequency error calculation circuit (41) plots the time-change rates to generate a histogram and calculates a clock-frequency error from the histogram.
    Type: Grant
    Filed: December 18, 2003
    Date of Patent: November 4, 2008
    Assignee: Sony Corporation
    Inventors: Atsushi Yajima, Kazuhisa Funamoto, Yasunari Ikeda
  • Patent number: 7403472
    Abstract: The time required for switch the channel can be remarkably curtailed. When broadcasting signals through a plurality of information channels with an OFDM system, the plurality of information channels are multiplexed in the sense of frequency and collectively subjected to IFFT modulation for connected transmission instead of subjecting the plurality of information channels independently to OFDM modulation for transmission. With this arrangement, the efficiency of exploitation of frequencies is improved. According to the invention, the OFDM frames are synchronized for each information channel for the purpose of connected transmission. Then, the OFDM receiver can switch the information channel for signal reception, maintaining the frame synchronizing signals.
    Type: Grant
    Filed: March 25, 2005
    Date of Patent: July 22, 2008
    Assignee: Sony Corporation
    Inventors: Takahiro Okada, Yoshikazu Miyato, Yasunari Ikeda, Tamotsu Ikeda
  • Patent number: 7356094
    Abstract: A digital broadcast receiving apparatus for receiving a broadcast signal generated by combining sub signals modulated using a random sequence generated based on an initial value set in accordance with a frequency of a broadcast channel by a signal transmission control use signal and a main signal generated based on information source data and reproducing the information source data contained in the received broadcast signal.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: April 8, 2008
    Assignee: Sony Corporation
    Inventors: Yasunari Ikeda, Toshihisa Hyakudai, Takahiro Okada, Tamotsu Ikeda
  • Patent number: 7327669
    Abstract: A radio relay system (1) comprises a wireless camera (11) and a signal receiving relay station (12). The wireless camera (11) wirelessly transmits signals to the signal receiving relay station (12) by using the OFDM modulation method. The wireless camera (11) and the signal receiving relay station (12) perform energy dispersion at the time of transmission-line-coding/decoding a transport stream. The PRBS seed (initial value) to be used for the energy dispersion can be externally modified and the user can arbitrarily select a value for the seed.
    Type: Grant
    Filed: September 7, 2001
    Date of Patent: February 5, 2008
    Assignee: Sony Corporation
    Inventors: Yoshikazu Miyato, Yasunari Ikeda
  • Patent number: 7317930
    Abstract: A wireless transmission/reception system is provided which can use a limited frequency band most effectively and operates flexibly. A receiver (wireless receiver) has a transmission processing unit for transmitting a control signal, which defines a wireless frequency band and a transmission frequency for each of wireless transmission signals, to a plurality of cameras (wireless transmitter) #C1 to #C5, and the cameras have reception processing units for receiving the controls signal. Each of the cameras can change the frequency band and a center frequency of the wireless transmission signal according to the input control signal. As a result, output channels (Ch1 to Ch5) of the receiver can be changed to a broadband channel or a narrowband channel arbitrarily.
    Type: Grant
    Filed: February 14, 2005
    Date of Patent: January 8, 2008
    Assignee: Sony Corporation
    Inventor: Yasunari Ikeda
  • Publication number: 20070297322
    Abstract: A radio relay system (1) comprises a wireless camera (11) and a signal receiving relay station (12). The wireless camera (11) wirelessly transmits signals to the signal receiving relay station (12) by using the OFDM modulation method. The wireless camera (11) and the signal receiving relay station (12) perform energy dispersion at the time of transmission-line-coding/decoding a transport stream. The PRBS seed (initial value) to be used for the energy dispersion can be externally modified and the user can arbitrarily select a value for the seed.
    Type: Application
    Filed: August 20, 2007
    Publication date: December 27, 2007
    Inventors: Yoshikazu Miyato, Yasunari Ikeda
  • Patent number: 7170850
    Abstract: A transmission apparatus which prevents adversely affects from an adjacent channel even without provision of a guard band. An information sequence 1 input to a mapping unit 21-1 of the transmission apparatus is mapped onto predetermined signal points by QAM modulation, etc. and output to a frequency converter 22-1. The frequency converter 22-1 converts the frequency according to a center frequency of an input signal and outputs the result to a multiplexer 23. The other data series are processed in the same way as the data series 1 are output to the multiplexer 23. The multiplexer 23 multiplexes a plurality of input signals, while an IFFT processor 24 performs an inverse Fourier transform on the multiplexed signals all at once. The inverse Fourier transformed signal is quadrature-modulated by a quadrature modulator 26, converted to the RF band signal by the frequency converter 28, and transmitted from an antenna 30.
    Type: Grant
    Filed: August 29, 2005
    Date of Patent: January 30, 2007
    Assignee: Sony Corporation
    Inventors: Takahiro Okada, Yasunari Ikeda
  • Patent number: 7158475
    Abstract: Influence from an adjacent signal is prevented even if a guard band is not provided. A phase comparison unit 21 compares a reference window signal input to a PLL circuit 4 and a window signal supplied from a frequency division circuit 22 and outputs the comparison result to an LPF 23. The LPF 23 extracts a low frequency component from the input signal and outputs the same to a voltage controlled oscillator 24. The signal output from the voltage controlled oscillator 24 is supplied as a clock to units of an OFDM modulation circuit 2 and, at the same time, supplied to the frequency division circuit 22. The frequency division circuit 22 divides the frequency of the supplied signal to thereby generate a new window signal and supplies the same to an IFFT unit 13. Further, the generated window signal is supplied to a PLL circuit 5. The PLL circuit 5 generates a clock for controlling a frequency modulation circuit 3 based on the supplied window signal.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: January 2, 2007
    Assignee: Sony Corporation
    Inventors: Yasunari Ikeda, Tamotsu Ikeda, Takahiro Okada
  • Patent number: 7079602
    Abstract: An interference signal from an adjacent signal is prevented and a desired signal demodulated. A frequency conversion circuit 4 converts a received signal frequency to a first intermediate frequency signal of a first intermediate frequency higher than the frequency of the signal to be demodulated by 57 MHz. The first intermediate frequency signal is further converted to a second intermediate frequency signal of a second intermediate frequency by a frequency conversion circuit 8. The second intermediate frequency is a frequency lower than the 57 MHz of the first intermediate frequency by exactly a frequency ½ of an FFT sampling f-clock. A clock generation circuit 11 generates a signal of a frequency two times the FFT sampling clock, that is, four times the second intermediate frequency.
    Type: Grant
    Filed: March 17, 2000
    Date of Patent: July 18, 2006
    Assignee: Sony Corporation
    Inventors: Yasunari Ikeda, Taiwa Okanobu
  • Patent number: 7075949
    Abstract: The time required for switch the channel can be remarkably curtailed. When broadcasting signals through a plurality of information channels with an OFDM system, the plurality of information channels are multiplexed in the sense of frequency and collectively subjected to IFFT modulation for connected transmission instead of subjecting the plurality of information channels independently to OFDM modulation for transmission. With this arrangement, the efficiency of exploitation of frequencies is improved. According to the invention, the OFDM frames are synchronized for each information channel for the purpose of connected transmission. Then, the OFDM receiver can switch the information channel for signal reception, maintaining the frame synchronizing signals.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: July 11, 2006
    Assignee: Sony Corporation
    Inventors: Takahiro Okada, Yoshikazu Miyato, Yasunari Ikeda, Tamotsu Ikeda
  • Patent number: 7076725
    Abstract: A wireless relay system (1) comprises a wireless camera (11) and a reception relay station (12). The reception relay station (12) comprises a plurality of external reception units (13) arranged at spatially different positions and an internal reception unit (14). Each reception section (16) in the internal reception unit (14) demodulates a signal received in the external reception unit (13) and outputs a transport stream. At this time, each reception section (16) sets an error indicator flag to 1 for a TS packet causing a transmission error which exceeds the error correction capability. A TS synthesizer section (17) in the internal reception unit (14) completely synchronizes a plurality of input transport streams by referencing synchronization bytes, PID, and CC values, and selects to output a TS packet having the error indicator flag not set to 1.
    Type: Grant
    Filed: September 7, 2001
    Date of Patent: July 11, 2006
    Assignee: Sony Corporation
    Inventors: Yasunari Ikeda, Norihisa Shirota, Hideyuki Matsumoto
  • Publication number: 20060002288
    Abstract: A transmission apparatus which prevents adversely affects from an adjacent channel even without provision of a guard band. An information sequence 1 input to a mapping unit 21-1 of the transmission apparatus is mapped onto predetermined signal points by QAM modulation, etc. and output to a frequency converter 22-1. The frequency converter 22-1 converts the frequency according to a center frequency of an input signal and outputs the result to a multiplexer 23. The other data series are processed in the same way as the data series 1 are output to the multiplexer 23. The multiplexer 23 multiplexes a plurality of input signals, while an IFFT processor 24 performs an inverse Fourier transform on the multiplexed signals all at once. The inverse Fourier transformed signal is quadrature-modulated by a quadrature modulator 26, converted to the RF band signal by the frequency converter 28, and transmitted from an antenna 30.
    Type: Application
    Filed: August 29, 2005
    Publication date: January 5, 2006
    Inventors: Takahiro Okada, Yasunari Ikeda
  • Patent number: 6980509
    Abstract: A transmission apparatus which prevents adversely affects from an adjacent channel even without provision of a guard band. An information sequence 1 input to a mapping unit 21-1 of the transmission apparatus is mapped onto predetermined signal points by QAM modulation, etc. and output to a frequency converter 22-1. The frequency converter 22-1 converts the frequency according to a center frequency of an input signal and outputs the result to a multiplexer 23. The other data series are processed in the same way as the data series 1 are output to the multiplexer 23. The multiplexer 23 multiplexes a plurality of input signals, while an IFFT processor 24 performs an inverse Fourier transform on the multiplexed signals all at once. The inverse Fourier transformed signal is quadrature-modulated by a quadrature modulator 26, converted to the RF band signal by the frequency converter 28, and transmitted from an antenna 30.
    Type: Grant
    Filed: March 6, 2000
    Date of Patent: December 27, 2005
    Assignee: Sony Corporation
    Inventors: Takahiro Okada, Yasunari Ikeda
  • Patent number: 6973118
    Abstract: A frequency interleaving circuit frequency-interleaves main signals generated according to sound data by parameters set according to frequencies of transmission channels. A sub-signal generating circuit generates sub-signals for transmission control including pilot signals. Mapping circuits modulate the sub-signals by using pseudo-random sequences generated based on initial values of random codes set according to frequencies of transmission channels. The frequency-interleaved main signals and the sub-signals modulated by the mapping circuits are OFDM-modulated. Then, they are converted to the frequencies of the transmission channels. An increase of a dynamic range of transmission signals can be suppressed by controlling the initial values of random codes set.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: December 6, 2005
    Assignees: Sony Corporation, Nippon Hoso Kyokai
    Inventors: Yasunari Ikeda, Toshihisa Hyakudai, Takahiro Okada, Tamotsu Ikeda, Toru Kuroda, Naohiko Iai, Kenichi Tsuchida, Makoto Sasaki
  • Patent number: 6956812
    Abstract: A reception apparatus for OFDM signals having a short initial rise time since start of reception until outputting the sound and/or a picture. An OFDM reception apparatus 1 of the ISDB-T standard presets the TMCC information at the outset in a memory 19 in association with each broadcasting station. This TMCC information contains the information on the RF frequency and the guard interval length, time interleaving pattern information, the information on the carrier modulation scheme and the information on the code rate of the convolutional code. When a user selects a broadcasting station, a control circuit 18 reads out the TMCC information associated with the broadcasting station from the memory 19. The control circuit 18 affords the read-out TMCC information to each circuit to set e.g., the guard interval or the carrier modulation scheme.
    Type: Grant
    Filed: April 5, 2001
    Date of Patent: October 18, 2005
    Assignee: Sony Corporation
    Inventors: Takahiro Okada, Toshihisa Hyakudai, Isao Matsumiya, Yasunari Ikeda
  • Publication number: 20050198672
    Abstract: A wireless transmission/reception system is provided which can use a limited frequency band most effectively and operates flexibly. A receiver (wireless receiver) has a transmission processing unit for transmitting a control signal, which defines a wireless frequency band and a transmission frequency for each of wireless transmission signals, to a plurality of cameras (wireless transmitter) #C1 to #C5, and the cameras have reception processing units for receiving the controls signal. Each of the cameras can change the frequency band and a center frequency of the wireless transmission signal according to the input control signal. As a result, output channels (Ch1 to Ch5) of the receiver can be changed to a broadband channel or a narrowband channel arbitrarily.
    Type: Application
    Filed: February 14, 2005
    Publication date: September 8, 2005
    Inventor: Yasunari Ikeda
  • Publication number: 20050169166
    Abstract: The time required for switch the channel can be remarkably curtailed. When broadcasting signals through a plurality of information channels with an OFDM system, the plurality of information channels are multiplexed in the sense of frequency and collectively subjected to IFFT modulation for connected transmission instead of subjecting the plurality of information channels independently to OFDM modulation for transmission. With this arrangement, the efficiency of exploitation of frequencies is improved. According to the invention, the OFDM frames are synchronized for each information channel for the purpose of connected transmission. Then, the OFDM receiver can switch the information channel for signal reception, maintaining the frame synchronizing signals.
    Type: Application
    Filed: March 25, 2005
    Publication date: August 4, 2005
    Inventors: Takahiro Okada, Yoshikazu Miyato, Yasunari Ikeda, Tamotsu Ikeda
  • Publication number: 20050147186
    Abstract: An OFDM demodulation (1) is provided which includes a guard correlation/peak time detection circuit (12) to generate a peak timing Np of a guard interval correlation value, and a timing synchronization circuit (13) to estimate a symbol-boundary time Nx from the peak timing Np. The timing synchronization circuit (13) calculates the symbol-boundary time Nx by filtering the peak time Np by a DLL (delay locked loop) filter (43). Further, the DLL filter (43) includes a limiter (52) to limit the range of phase-error component and an asymmetric gain circuit (53) to change the magnitude of the gain correspondingly to the polarity of the phase error to prevent the timing from being pulled out due to a fading or multipath.
    Type: Application
    Filed: December 18, 2003
    Publication date: July 7, 2005
    Inventors: Kazuhisa Funamoto, Takahiro Okada, Tamotsu Ikeda, Atsushi Yajima, Yasunari Ikeda
  • Publication number: 20050117667
    Abstract: An OFDM receiver (1) is provided which includes a clock-frequency error calculation circuit (41) to calculate a difference in clock frequency between a clock for a received signal and an operation clock used in the receiver (1), and a guard correlation/peak detection circuit (12) to determine an autocorrelation of a guard interval and detect a peak timing of the correlation signal. The guard correlation/peak detection circuit (12) incorporates a free-running counter, and outputs a count of the free-running counter at the peak timing to the clock-frequency error calculation circuit (41). The clock-frequency error calculation circuit (41) uses a plurality of time-change rate detection circuits provided at different time intervals to calculate a time-change rate of an input count. The clock-frequency error calculation circuit (41) plots the time-change rates to generate a histogram and calculates a clock-frequency error from the histogram.
    Type: Application
    Filed: December 18, 2003
    Publication date: June 2, 2005
    Inventors: Atsushi Yajima, Kazuhisa Funamoto, Yasunari Ikeda